The rational configuration of built-in electric field(IEF)in heterogeneous materials can significantly optimize the band structure to accelerate the separation of photogenerated charge carriers.However,the strength mo...The rational configuration of built-in electric field(IEF)in heterogeneous materials can significantly optimize the band structure to accelerate the separation of photogenerated charge carriers.However,the strength modulation of IEF formed by various materials has an uncertain enhancing effect on the separation of photogenerated carriers.Herein,a mesoporous MIL-125(Ti)@BiOCl S-scheme heterojunction with controllable IEF is prepared by green photoreduction reaction to investigate the relationship between IEF,microstructure,and photocatalytic activity.Moreover,the corresponding results demonstrate the MIL-125(Ti)@BiOCl effectively regulates the IEF strength through controlling the concentration of ligand defects,thereby optimizing the band structure and improving the efficiency of photogenerated charge separation.The optimized IEF significantly enhances the photocatalytic degradation performance of mesoporous MIL-125(Ti)-3@BiOCl towards tetracycline,with a k value of 0.07 min^(–1),which are approximately 5.5 and 4.7 times greater than that of BiOCl(0.0127 min^(–1))and MIL-125(Ti)-3(0.015 min^(–1)).These findings provide a new pathway for regulating IEF within MOF-based heterojunctions,and offer new insights into the intrinsic correlations between defect structure,IEF,and photocatalytic activity.展开更多
Bifunctional Ir catalysts for proton exchange membrane(PEM)water electrolysis offer transformative potential by streamlining electrolyzer while achieving efficient performance remains challenging due to the distinct c...Bifunctional Ir catalysts for proton exchange membrane(PEM)water electrolysis offer transformative potential by streamlining electrolyzer while achieving efficient performance remains challenging due to the distinct conditions required for oxygen and hydrogen evolution reaction(OER and HER).Herein,we propose a theory-directed design of Ir-based bifunctional catalysts,Ir nanoparticles supported on mesoporous carbon spheres embedded with MoSe_(2)(Ir/MoSe_(2)@MCS),leveraging a work function(WF)-induced spontaneous built-in electric field to enhance catalytic performance.They demonstrate exceptional kinetics for both OER and HER,and potential application in the practical PEM electrolyzer,showcasing the effectiveness of this innovative approach.Low overpotentials of 252 mV for OER and 28 mV for HER to drive 10 mA cm^(-2)were observed,and the PEM electrolyzer showed the current density of 2 A cm^(-2)at 1.87 V and maintained stable activity at 1.65 V for over 30 h to deliver 1 A cm^(-2).Density functional theory calculations reveal that the WF difference at Ir/MoSe_(2)interface induces a spontaneous built-in electric field with asymmetric charge distributions,that modulate the electronic environment and d-band center of Ir promoting bifunctional active phase formation.This significantly lowers reaction barriers for water splitting by balancing intermediate adsorption,endowing the bifunctional activity.展开更多
The pursuit of high-purity,high-energy-density green hydrogen via water electrolysis remains a signif-icant challenge.This work reports the successful synthesis of a novel NiWO_(4)-Ni_(2)P heterostructure enriched wit...The pursuit of high-purity,high-energy-density green hydrogen via water electrolysis remains a signif-icant challenge.This work reports the successful synthesis of a novel NiWO_(4)-Ni_(2)P heterostructure enriched with abundant interfacial sites.Leveraging electron transfer from NiWO_(4)to Ni_(2)P,the resulting NiWO_(4)-Ni_(2)P electrocatalyst exhibits exceptional hydrogen evolution reaction(HER)performance.Combined experimental and theoretical studies demonstrate that the built-in electric field(BIEF)at the NiWO4-Ni2 P interface induces charge redistribution,modulating the d-band center and optimizing hydro-gen adsorption,thus leading to superior HER activity.An assembled NiFe LDH||NiWO_(4)-Ni_(2)P electrolyzer achieves a current density of 10 mA cm^(−2)at only 1.51 V in 1 M KOH.Furthermore,the NiWO_(4)-Ni_(2)P electrocatalyst and electrolyzer maintain remarkable electrocatalytic performance for hydrogen produc-tion even in seawater.This study offers a new approach for the rational design and development of high-performance heterogeneous electrocatalysts for hydrogen production from water splitting and other energy conversion applications.展开更多
The quest for sustainable energy solutions has intensified the need for efficient water electrolysis techniques,pivotal for hydrogen production.However,developing effective bifunctional electrocatalysts capable of dri...The quest for sustainable energy solutions has intensified the need for efficient water electrolysis techniques,pivotal for hydrogen production.However,developing effective bifunctional electrocatalysts capable of driving the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)remains a formidable challenge.Addressing this,we introduce a novel built-in electric field(BEF)strategy to synthesize NiCoP–Co nanoarrays directly on Ti_(3)C_(2)T_(x) MXene substrates(NiCoP–Co/MXene).This approach leverages a significant work function difference(ΔΦ),propelling these nanoarrays as adept bifunctional electrocatalysts for comprehensive water splitting.MXene,in this process,plays a dual role.It acts as a conductive support,enhancing the catalyst’s overall conductivity,and facilitates an effective charge transport pathway,ensuring efficient charge transfer.Our study reveals that the BEF induces an electric field at the interface,prompting charge transfer from Co to NiCoP.This transfer modulates asymmetric charge distributions,which intricately control intermediates’adsorption and desorption dynamics.Such regulation is crucial for enhancing the reaction kinetics of both HER and OER.Furthermore,under oxidative conditions,the NiCoP–Co/MXene catalyst undergoes a structural metamorphosis into Ni(Co)oxides/hydroxides/MXene,increasing OER performance.This research demonstrates the BEF’s role in fine-tuning interfacial charge redistribution and underscores its potential in crafting more sophisticated electrocatalytic designs.The insights gained here could pave the way for the next generation of electrocatalysis,with far-reaching implications for energy conversion and storage technologies.展开更多
Silicon(Si)anodes,with a theoretical specific capacity of 4200 mAh g^(-1),hold significant promise for the development of high-energy-density lithium-ion batteries(LIBs).However,practical applications are hindered by ...Silicon(Si)anodes,with a theoretical specific capacity of 4200 mAh g^(-1),hold significant promise for the development of high-energy-density lithium-ion batteries(LIBs).However,practical applications are hindered by sluggish charge transfer kinetics,substantial volume expansion,and an unstable solid elec-trolyte interphase during cycling.To address these challenges,we propose a centimeter-scale Si anode design featuring a three-dimensional continuous network structure of Si nanowires(SiNWs)decorated with high-density Ag nanoparticles(Ag-SiNWs-Net)on both the surface and internally.This architecture effectively mitigates mechanical stress from Si volume changes through the high-aspect-ratio wire network.Additionally,the distribution of Ag nanoparticles on the Si induces electronic structure redistribution,generating built-in electric fields that accelerate charge transfer within the Si,significantly enhancing rate performance and cycling stability.The Ag-SiNWs-Net anode achieves a high reversible capacity of 3780.9 mAh g^(-1)at 0.1 A g^(-1),with an initial coulombic efficiency of 85.1%.Moreover,the energy density of full cells assembled with Ag-SiNWs-Net anodes and LiFePO4 cathodes can be pushed further up to 395.8 Wh kg^(-1).This study offers valuable insights and methodologies for the development of high-capacity and practical Si anodes-.展开更多
Solvated zinc ions are prone to undergo desolvation at the electrode/electrolyte interfaces,and unstable H_(2)O molecules within the solvated sheaths tend to trigger hydrogen evolution reaction(HER),further accelerati...Solvated zinc ions are prone to undergo desolvation at the electrode/electrolyte interfaces,and unstable H_(2)O molecules within the solvated sheaths tend to trigger hydrogen evolution reaction(HER),further accelerating interfaces decay.Herein,we propose for the first time a novel strategy to enhance the interfacial stabilities by insitu dynamic reconstruction of weakly solvated Zn2þduring the desolvation processes at heterointerfaces.Theoretical calculations indicate that,due to built-in electric field effects(BEFs),the plating/stripping mechanism shifts from[Zn(H_(2)O)_(6)]_(2)þto[Zn(H_(2)O)_(5)(SO_(4))^(2-)]_(2)þwithout additional electrolyte additives,reducing the solvation ability of H_(2)O,enhancing the competitive coordination of SO_(4)^(2-),essentially eliminating the undesirable side effects of anodes.Hence,symmetric cells can operate stably for 3000 h(51.7-times increase in cycle life),and the full cells can operate stably for 5000 cycles(51.5-times increase in cycle life).This study provides valuable insights into the critical design of weakly solvated Zn^(2+) þand desolvation processes at heterointerfaces.展开更多
The advanced oxidation process presents a perfect solution for eliminating organic pollutants in water resources,and the local microenvironment and surface state of metal reactive sites are crucial for the selective a...The advanced oxidation process presents a perfect solution for eliminating organic pollutants in water resources,and the local microenvironment and surface state of metal reactive sites are crucial for the selective activation of peroxomonosulfate(PMS),which possibly determines the degradation pathways of organic contaminants.In this study,by virtue of the precursor alternation,we constructed the state-switched dual metal species with the porous carbon fibers through the electrospinning strategy.Impressively,the optimal catalyst,featuring the electron-deficient cobalt surface oxidative state and most abundant oxygen vacancies(Ov)with MnO_(2)within porous carbon fibers,provides abundant mesoporosity,facilitating the diffusion and accommodation of big carbamazepine molecules during the reaction process.Benefiting from the tandem configuration of carbon fiber-encapsulated nanocrystalline species,a p-n heterojunction configuration evidenced by Mott-Schottky analysis induced local built-in electric field(BIEF)between electron-deficient cobalt and Ov-rich MnO_(2)within carbon matrix-mediated interfacial interactions,which optimizes the adsorption and activation of PMS and intermediates,increases the concentration of reactive radicals around the active site,and significantly enhances the degradation performance.As a result,the optimal catalyst could achieve 100%degradation of 20 ppm carbamazepine(CBZ)within only 4 min with a rate constant of 1.099 min^(-1),showcasing a low activation energy(50 kJ mol^(-1)),obviously outperforming the other counterparts.We further demonstrated the generation pathways of active species by activation of PMS mainly including sulfate radical(·SO_(4)^(-)),hydroxyl radical(·OH),superoxide radicals(·O_(2)^(-)),and singlet oxygen(^(1)O_(2)),unveiling their contribution to CBZ degradation.The degradation route of CBZ and toxicity analysis of various intermediates were further evaluated.By anchoring the optimal catalyst onto polyester fiber sponge,the photothermal conversion synergistic monolith floatable catalyst and its easy recovery can be achieved,showing good reproducibility and generalizability in the practical application.展开更多
Heterointerface engineering based on built-in electric field(BIEF)has been well-received in electromagnetic wave(EMW)absorption.However,the influence of interface size and number of interfaces on the BIEF and interfac...Heterointerface engineering based on built-in electric field(BIEF)has been well-received in electromagnetic wave(EMW)absorption.However,the influence of interface size and number of interfaces on the BIEF and interface polarization loss mechanism remains unclear.Here,we designed a ternary dual het-erointerfaces Co@C/SiO_(2)nanocomposite.Experimental and theoretical analyses show that Co@C/SiO_(2)has abundant Mott-Schottky heterointerfaces,and a reasonable increase in the heterointerface area leads to a strong BIEF effect,where the charge accumulates at the interface and subsequently migrates along the direction of the alternating electromagnetic field to promote the dissipation of EMW by polarization loss.However,an excessive number of interfaces leads to many carriers being bound by the interfaces,which is not conducive to forming electron channels.By coordinating the heterointerface states to achieve optimal EMW absorption performance,SZ-3 can accomplish an effective absorption width(EAB)of 5.93 GHz at a thickness of 1.91 mm.This work provides new ideas and methods for BIEF-based heterointerface engineering applied to EMW absorption materials.展开更多
Understanding dynamic storage mechanisms and tuning electrode interfaces is vital for designing highperformance potassium-ion battery(KIB)anodes.Despite their high capacities,transition metal telluride(TMTe)anodes oft...Understanding dynamic storage mechanisms and tuning electrode interfaces is vital for designing highperformance potassium-ion battery(KIB)anodes.Despite their high capacities,transition metal telluride(TMTe)anodes often suffer from sluggish K+diffusion and severe volume expansion during cycling,highlighting the need for structurally optimized and interface-engineered architectures.While such strategies have been proven to be effective in lithium-and sodium-ion batteries,their use in TMTe-based KIB anodes remains largely unexplored.In this study,we firstly introduce a heterointerface-engineered three-dimensional microsphere composed of ZnTe nanoparticles and uniformly encapsulated by MXene(denoted MX/ZnTe@NC).Importantly,a built-in electric field(BIEF)is induced at the MXeneZnTe interface due to their work function.This interfacial field modulates the local electronic structure and significantly accelerates K^(+)adsorption and diffusion kinetics,especially under high current densities.First-principles simulations and spectroscopic analyses confirm that the BIEF significantly increases the K~+adsorption strength and lowers the energy barriers for ion transport.Electrochemical analyses reveal that the MX/ZnTe@NC anode delivers a high reversible capacity of 283 mAh g^(-1)after 1000 cycles at 0.5 A g^(-1),with nearly 100%Coulombic efficiency.Even at 10 A g^(-1),the anode retains a capacity of 83 mAh g^(-1),indicating excellent rate performance.Additionally,in-situ and ex-situ characterizations reveal a highly reversible ZnTe conversion mechanism involving dynamic intermediate phases.This study provides mechanistic insight into the structural and chemical evolution during cycling and highlights the synergistic role of interfacial field engineering and three-dimensional heterostructure design in advancing MXene-based KIB anodes.展开更多
Constructing heterostructures and facilitating surface reconstruction are effective ways to obtain excellent catalysts for the oxygen evolution reaction(OER).Surface reconstruction is a dynamic process that is affecte...Constructing heterostructures and facilitating surface reconstruction are effective ways to obtain excellent catalysts for the oxygen evolution reaction(OER).Surface reconstruction is a dynamic process that is affected by the built-in electric field of the heterostructure.In this study,P/N co-doped carbon-coated NiCo/Ni-CoO heterostructure was prepared by in situ acid etching,aniline polymerization,and pyrolysis.This method can form a tightly connected heterogeneous interface.It was found that introducing P-O bonds in the carbon shell can increase its work function,thereby enhancing the built-in electric field between the carbon shell and the core catalyst.Detailed characterizations confirm that the P-O bridge at the heterogeneous interface can provide an electron flow highway from the core to the shell.The generated carbon defects generated by P leaching during surface reconstruction also have strong electronabsorbing capacity.These effects promote the conversion of Co^(2+)to Co^(3+),thereby providing more highly active sites.The resulting catalyst shows significantly enhanced activity and stability.This study demonstrates the promoting effect of the built-in electric field on the surface reconstruction of the catalyst and emphasizes the importance of the construction of tightly connected heterogeneous interface,which is instructive for the design of excellent OER catalysts.展开更多
Built-in electric fields(BIEF),engineered via space charge manipulation,represent an effective strategy for enhance electromagnetic loss.However,single BIEF fail to reconcile the impedance matching and strong electrom...Built-in electric fields(BIEF),engineered via space charge manipulation,represent an effective strategy for enhance electromagnetic loss.However,single BIEF fail to reconcile the impedance matching and strong electromagnetic attenuation across broad frequency spectra,resulting in limited effective absorption bandwidth(EAB).To address this,dual-BIEF are constructed utilizing an asymmetric gradient electric field structure and multi-polarization center coordination to achieve high-efficiency broad EAB.Herein,heterostructure Ni-Co bimetallic nanocomposites(Ni_(0.5)Co_(0.5)@NiCoO_(2)/NCP)are constructed via Ni-Co-based nanocomposites(NiCoO_(2)and Ni_(0.5)Co_(0.5))integrated with nitrogen-doped nanoporous carbon(NCP).This configuration forms dual heterojunctions the NCP-NiCoO_(2)-semiconductor heterojunction and the NiCoO_(2)-Ni_(0.5)Co_(0.5)Mott-Schottky heterojunction—forming the dual-BIEF system.The superposed dual-BIEF drives charge-pumping dynamics facilitating oriented transfer and transition of charges that strengthen interfacial polarization and reduced relaxation times.Theoretical calculations confirm this system simultaneously modulates conductivity,intensifies polarization relaxation,promotes charge separation,and optimizes dipole distribution.Dielectric loss from semiconductor junctions dominates the low-frequency regime,while conductive loss via Mott-Schottky junctions prevails at high frequencies.Thus,the Ni_(0.5)Co_(0.5)@NiCoO_(2)/NCP achieves excellent microwave absorption with a remarkable minimum reflection loss of51.5 dB,and an EAB of 6.4 GHz at 2.8 mm thickness.This work establishes a dual-BIEF strategy for effectively engineering high-performance electromagnetic wave absorption materials.展开更多
Rational design of defected carbons adjacent to nitrogen(N)dopants is a fascinating but challenging approach for enhancing the catalytic performance of N-doped carbon.Meanwhile,the combined effect of heteroatom doping...Rational design of defected carbons adjacent to nitrogen(N)dopants is a fascinating but challenging approach for enhancing the catalytic performance of N-doped carbon.Meanwhile,the combined effect of heteroatom doping and defect engineering can efficiently increase the oxygen reduction reaction(ORR)ability of inactive carbons through charge redistribution.Herein,we report that an enhanced built-in electric field caused by the combined effect of N-doping and carbon defects in the twodimensional(2D)mesoporous N-doped carbon nano flakes(NCNF)is a promising technique for improving ORR performance.As a result,the NCNF exhibits more promising ORR activity than Pt/C and similar performance with reported robust catalysts.Comprehensive experimental and theoretical investigations suggest that topologically defected carbon adjacent to the graphitic valley nitrogen is a real active site,rendering optimal energy for the adsorption of ORR intermediates and lowering the total energy barrier for ORR.Also,NCNF-based Zn-air batteries exhibited an excellent power density and specific capacity of~121.10 mW cm^(-2)and~679.86 mA h g_(Zn)^(-1),respectively.This study not only offers new insights into defected carbons with graphitic valley N for ORR but also proposes novel catalyst design principles and provides a solid grasp of the built-in electric field effect on the ORR performance of defective catalysts.展开更多
Transition metal selenides(TMS)demonstrate exceptional catalytic activity in the oxygen evolution reaction(OER),yet their performance is hindered by surface reconstruction under OER conditions,particularly at high cur...Transition metal selenides(TMS)demonstrate exceptional catalytic activity in the oxygen evolution reaction(OER),yet their performance is hindered by surface reconstruction under OER conditions,particularly at high current densities.This study reveals that embedding Co_(0.85)Se nanoparticles into the interlayer spacing of MXene-Ti_(3)C_(2)effectively suppresses surface reconstruction during OER.This configuration establishes a Schottky heterojunction with an intrinsic built-in electric field(BEF)between Co_(0.85)Se and Ti_(3)C_(2),which enhances charge redistribution and accelerates electron transport.Consequently,the Co_(0.85)Se@Ti_(3)C_(2)composite exhibits outstanding OER performance,achieving low overpotentials(230 m V at 100 m A/cm^(2),376 m V at 1000 m A/cm^(2),417 m V at 1500 m A/cm^(2))and exceptional durability(200 h at200 m A/cm^(2)).In-situ XRD/Raman characterization verifies that the encapsulated Co_(0.85)Se within Ti_(3)C_(2)inhibits CoOOH formation on the surface during OER.Both experimental and theoretical investigations indicate that the heterojunction's superhydrophilicity/superaerophobicity,synergized with BEF-regulated oxygen intermediate adsorption/desorption,collectively enhance catalytic efficiency of Co_(0.85)Se@Ti_(3)C_(2).This strategy of spatially confining chalcogenide catalysts to prevent structural degradation while leveraging interfacial electric fields presents a rational approach for developing durable electrocatalysts in highcurrent densities water electrolysis.展开更多
The built-in electric field(BIEF)aroused by the variation in charge distribution between the surface and bulk phase of carbon nitride can improve carrier dynamics.Herein,phosphorus(P)and benzene ringdoped C_(3)N_(5)na...The built-in electric field(BIEF)aroused by the variation in charge distribution between the surface and bulk phase of carbon nitride can improve carrier dynamics.Herein,phosphorus(P)and benzene ringdoped C_(3)N_(5)nanosheets(PPCN_(2))were synthesized by a facile method and demonstrated excellent performance in the photocatalytic degradation of antibiotics.Benzene ring replaced the triazine part of the heptazine unit,expanding the π-conjugated structure of the system,promoting electron delocalization,and enhancing the light-absorbing property.P doping led to the creation of an additional donor state within the P 2p band,facilitating the charge separation and lengthening the transport distance of electron-hole pairs.Additionally,the intermediate state gap created in the Urbach tail further strengthened photon absorption and improved effective electron capture.XPS with Ar ion etching at different depths verified the significant potential difference and large dipole moment caused by different doping levels of surface and bulk phase,resulting in a strong BIEF inside the PPCN_(2).KPFM,SPV,and DFT calculations confirmed the strong BIEF in PPCN_(2).EPR,rotating disk electrode(RRDE)and in situ infrared drift(DRIFT)spectroscopy confirmed the reactive oxygen species and the two-step one-electron reduction reaction mechanism during the photodegradation process.This work provides a new perspective for the study of improving the photocatalytic performance of C_(3)N_(5)by inducing the BIEF which arose from the differences in electronic structure and charge distribution on the surface and bulk phase caused by molecular doping.展开更多
To develop a melting-based larger-scale fabrication process for oxide dispersion strengthened(ODS)steel,this study proposed a method of zone melting with built-in precursor powder(ZMPP),followed by hot forging and agi...To develop a melting-based larger-scale fabrication process for oxide dispersion strengthened(ODS)steel,this study proposed a method of zone melting with built-in precursor powder(ZMPP),followed by hot forging and aging treatments.A 50 kg ingot was successfully prepared,highlighting the scalability of this innovative process.Microstructural analysis revealed a predominantly lath martensite matrix with a small amount of ferrite in the hot-forged ODS steel,without oxide particle aggregation.Aging at 750℃ resulted in the formation of sub-micron-sized Cr_(23)C_(6) particles at grain boundaries and martensitic lath interfaces,accompanied by a high-density(7.64×1023 m^(-3))nano-scale(~6 nm)Y-Si-O complex oxides after 25 h.Additionally,the hot-forged sample exhibited a high yield strength(871 MPa)but limited ductility(5.0%).Aging treatments led to an increase in ductility but a decrease in yield strength.Notably,prolonged aging maintained the strength level of steels while enhancing ductility,with a 23.3% total elongation observed after 25 h.The novel ZMPP method,preparing high-quality ODS steels with uniform microstructure and good mechanical properties,provided a new avenue for large-scale production of ODS steels.展开更多
Designing a heterogeneous interface to improve the kinetics of electrocatalysts represents an effective yet challenging approach for enhancing the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).Herei...Designing a heterogeneous interface to improve the kinetics of electrocatalysts represents an effective yet challenging approach for enhancing the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).Herein,a simple MOF-assisted etching-pyrolysis strategy is proposed to fabricate an advanced Mott-Schottky(M–S)electrocatalyst composed of Co/CeO_(2)hetero-nanoparticles embedded within N-doped hollow carbon nanoboxes(H-Co/CeO_(2)@NCBs).Notably,the interfacial Co–O–Ce bond bridging productively facilitates the electron transfer and modulates the charge distribution of the active center,thereby contributing to the ORR/OER kinetics.As expected,the optimal M–S H-Co/CeO_(2)@NCBs catalyst exhibits promising bifunctional electrocatalytic activity with a small potential discrepancy of 0.65 V.Theoretical calculations reveal that the built-in electric field in the M–S heterojunction promotes electron transfer in oxygen electrocatalysis and the interfacial bridge-induced electron redistribution optimizes the adsorption/desorption of the oxygen intermediates,leading to reduced activation energy for the bifunctional ORR/OER reactions.Importantly,H-Co/CeO_(2)@NCBs-assembled Zn-air battery(ZAB)delivers high power density(179.8 mW cm^(−2))and long-term stability(400 h).Furthermore,the assembled flexible solid-state ZAB with H-Co/CeO_(2)@NCBs cathode also exhibits excellent charge–discharge reversibility and flexibility at various bending angles.This work provides a novel perspective on developing efficient and stable M–S bifunctional oxygen electrocatalysts.展开更多
Rapid technological development and population growth are responsible for a series of imminent environmental problems and an ineluctable energy crisis.The application of semiconductor nanomaterials in photocatalysis o...Rapid technological development and population growth are responsible for a series of imminent environmental problems and an ineluctable energy crisis.The application of semiconductor nanomaterials in photocatalysis or photoelectrocatalysis(PEC)for either the degradation of contaminants in the environment or the generation of hydrogen as clean fuel is an effective approach to alleviate these problems.However,the efficiency of such processes remains suboptimal for real applications.Reasonable construction of a built-in electric field is considered to efficiently enhance carrier separation and reduce carrier recombination to improve catalytic performance.In the past decade,as a new method to enhance the built-in electric field,the piezoelectric effect from piezoelectric materials has been extensively studied.In this review,we provide an overview of the properties of piezoelectric materials and the mechanisms of piezoelectricity and ferroelectricity for a built-in electric field.Then,piezoelectric and ferroelectric polarization regulated built-in electric fields that mediate catalysis are discussed.Furthermore,the applications of piezoelectric semiconductor materials are also highlighted,including degradation of pollutants,bacteria disinfection,water splitting for H2 generation,and organic synthesis.We conclude by discussing the challenges in the field and the exciting opportunities to further improve piezo-catalytic efficiency.展开更多
The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterost...The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not monotonous.In this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky junctions.By skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching thickness.The successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW absorption.We detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal interfaces.The achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 mm.Radar cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth technology.This work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities.展开更多
An electron transporting material of TFTTP (4-(5-hexylthiophene-2-yl)-2,6-bis(5-trifluoromethyl)thiophen-2-yl)pyridine) was investigated as a cathode buffer layer to enhance the power efficiency of organic sola...An electron transporting material of TFTTP (4-(5-hexylthiophene-2-yl)-2,6-bis(5-trifluoromethyl)thiophen-2-yl)pyridine) was investigated as a cathode buffer layer to enhance the power efficiency of organic solar cells (OSCs) based on subphthalocyanine and C60. The overall power conversion efficiency was increased by a factor of 1.31 by inserting the TFTTP interfacial layer between the active layer and metallic cathode. The inner mechanism responsible for the performance enhancement of OSCs was systematically studied with the simulation of dark diode behavior and optical field distribution inside the devices as well as the characterization of device photocurrent. The results showed that the TFTTP layer could significantly increase the built-in potential in the devices, leading to the enhanced dissociation of charge transfer excitons. In addition, by using TFTTP as the buffer layer, a better Ohmic contact at C60/metal interface was formed, facilitating more efficient free charge carrier collection.展开更多
文摘The rational configuration of built-in electric field(IEF)in heterogeneous materials can significantly optimize the band structure to accelerate the separation of photogenerated charge carriers.However,the strength modulation of IEF formed by various materials has an uncertain enhancing effect on the separation of photogenerated carriers.Herein,a mesoporous MIL-125(Ti)@BiOCl S-scheme heterojunction with controllable IEF is prepared by green photoreduction reaction to investigate the relationship between IEF,microstructure,and photocatalytic activity.Moreover,the corresponding results demonstrate the MIL-125(Ti)@BiOCl effectively regulates the IEF strength through controlling the concentration of ligand defects,thereby optimizing the band structure and improving the efficiency of photogenerated charge separation.The optimized IEF significantly enhances the photocatalytic degradation performance of mesoporous MIL-125(Ti)-3@BiOCl towards tetracycline,with a k value of 0.07 min^(–1),which are approximately 5.5 and 4.7 times greater than that of BiOCl(0.0127 min^(–1))and MIL-125(Ti)-3(0.015 min^(–1)).These findings provide a new pathway for regulating IEF within MOF-based heterojunctions,and offer new insights into the intrinsic correlations between defect structure,IEF,and photocatalytic activity.
文摘Bifunctional Ir catalysts for proton exchange membrane(PEM)water electrolysis offer transformative potential by streamlining electrolyzer while achieving efficient performance remains challenging due to the distinct conditions required for oxygen and hydrogen evolution reaction(OER and HER).Herein,we propose a theory-directed design of Ir-based bifunctional catalysts,Ir nanoparticles supported on mesoporous carbon spheres embedded with MoSe_(2)(Ir/MoSe_(2)@MCS),leveraging a work function(WF)-induced spontaneous built-in electric field to enhance catalytic performance.They demonstrate exceptional kinetics for both OER and HER,and potential application in the practical PEM electrolyzer,showcasing the effectiveness of this innovative approach.Low overpotentials of 252 mV for OER and 28 mV for HER to drive 10 mA cm^(-2)were observed,and the PEM electrolyzer showed the current density of 2 A cm^(-2)at 1.87 V and maintained stable activity at 1.65 V for over 30 h to deliver 1 A cm^(-2).Density functional theory calculations reveal that the WF difference at Ir/MoSe_(2)interface induces a spontaneous built-in electric field with asymmetric charge distributions,that modulate the electronic environment and d-band center of Ir promoting bifunctional active phase formation.This significantly lowers reaction barriers for water splitting by balancing intermediate adsorption,endowing the bifunctional activity.
基金financially supported by the Guangdong Basic and Applied Basic Research Foundation(No.2023A1515140153)the Guangdong Special Innovative Projects of General Universities(No.2022KTSCX136)+1 种基金the Major and Special Project in Intelligent Manufacturing for Universities in Guangdong Province(No.2020ZDZX2067)the Innovative Team Project of Universities in Guangdong Province(No.2023KCXTD035).
文摘The pursuit of high-purity,high-energy-density green hydrogen via water electrolysis remains a signif-icant challenge.This work reports the successful synthesis of a novel NiWO_(4)-Ni_(2)P heterostructure enriched with abundant interfacial sites.Leveraging electron transfer from NiWO_(4)to Ni_(2)P,the resulting NiWO_(4)-Ni_(2)P electrocatalyst exhibits exceptional hydrogen evolution reaction(HER)performance.Combined experimental and theoretical studies demonstrate that the built-in electric field(BIEF)at the NiWO4-Ni2 P interface induces charge redistribution,modulating the d-band center and optimizing hydro-gen adsorption,thus leading to superior HER activity.An assembled NiFe LDH||NiWO_(4)-Ni_(2)P electrolyzer achieves a current density of 10 mA cm^(−2)at only 1.51 V in 1 M KOH.Furthermore,the NiWO_(4)-Ni_(2)P electrocatalyst and electrolyzer maintain remarkable electrocatalytic performance for hydrogen produc-tion even in seawater.This study offers a new approach for the rational design and development of high-performance heterogeneous electrocatalysts for hydrogen production from water splitting and other energy conversion applications.
基金supported by Guangdong Basic and Applied Basic Research Foundation(Nos.2021A1515010261 and 2023A1515140153)Guangdong Special Innovative Projects of General Universities(No.2022KTSCX136)+1 种基金the Major and Special Project in the Field of Intelligent Manufacturing of the Universities in Guangdong Province(No.2020ZDZX2067)the Innovative Team Project of the Universities in Guangdong Province(No.2023KCXTD035).
文摘The quest for sustainable energy solutions has intensified the need for efficient water electrolysis techniques,pivotal for hydrogen production.However,developing effective bifunctional electrocatalysts capable of driving the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)remains a formidable challenge.Addressing this,we introduce a novel built-in electric field(BEF)strategy to synthesize NiCoP–Co nanoarrays directly on Ti_(3)C_(2)T_(x) MXene substrates(NiCoP–Co/MXene).This approach leverages a significant work function difference(ΔΦ),propelling these nanoarrays as adept bifunctional electrocatalysts for comprehensive water splitting.MXene,in this process,plays a dual role.It acts as a conductive support,enhancing the catalyst’s overall conductivity,and facilitates an effective charge transport pathway,ensuring efficient charge transfer.Our study reveals that the BEF induces an electric field at the interface,prompting charge transfer from Co to NiCoP.This transfer modulates asymmetric charge distributions,which intricately control intermediates’adsorption and desorption dynamics.Such regulation is crucial for enhancing the reaction kinetics of both HER and OER.Furthermore,under oxidative conditions,the NiCoP–Co/MXene catalyst undergoes a structural metamorphosis into Ni(Co)oxides/hydroxides/MXene,increasing OER performance.This research demonstrates the BEF’s role in fine-tuning interfacial charge redistribution and underscores its potential in crafting more sophisticated electrocatalytic designs.The insights gained here could pave the way for the next generation of electrocatalysis,with far-reaching implications for energy conversion and storage technologies.
基金supported by the National Natural Science Foundation of China(No.61904130)the Key Research and Development Program of Hubei Province(Nos.2023BAB122,2021BAA063,and 2020BAB084)the Key Laboratory of Coal Conversion and New Carbon Materials in Hubei Province(No.WKDM201907)for their invaluable support.
文摘Silicon(Si)anodes,with a theoretical specific capacity of 4200 mAh g^(-1),hold significant promise for the development of high-energy-density lithium-ion batteries(LIBs).However,practical applications are hindered by sluggish charge transfer kinetics,substantial volume expansion,and an unstable solid elec-trolyte interphase during cycling.To address these challenges,we propose a centimeter-scale Si anode design featuring a three-dimensional continuous network structure of Si nanowires(SiNWs)decorated with high-density Ag nanoparticles(Ag-SiNWs-Net)on both the surface and internally.This architecture effectively mitigates mechanical stress from Si volume changes through the high-aspect-ratio wire network.Additionally,the distribution of Ag nanoparticles on the Si induces electronic structure redistribution,generating built-in electric fields that accelerate charge transfer within the Si,significantly enhancing rate performance and cycling stability.The Ag-SiNWs-Net anode achieves a high reversible capacity of 3780.9 mAh g^(-1)at 0.1 A g^(-1),with an initial coulombic efficiency of 85.1%.Moreover,the energy density of full cells assembled with Ag-SiNWs-Net anodes and LiFePO4 cathodes can be pushed further up to 395.8 Wh kg^(-1).This study offers valuable insights and methodologies for the development of high-capacity and practical Si anodes-.
基金financially supported by the National Natural Science Foundation of China(51977097).
文摘Solvated zinc ions are prone to undergo desolvation at the electrode/electrolyte interfaces,and unstable H_(2)O molecules within the solvated sheaths tend to trigger hydrogen evolution reaction(HER),further accelerating interfaces decay.Herein,we propose for the first time a novel strategy to enhance the interfacial stabilities by insitu dynamic reconstruction of weakly solvated Zn2þduring the desolvation processes at heterointerfaces.Theoretical calculations indicate that,due to built-in electric field effects(BEFs),the plating/stripping mechanism shifts from[Zn(H_(2)O)_(6)]_(2)þto[Zn(H_(2)O)_(5)(SO_(4))^(2-)]_(2)þwithout additional electrolyte additives,reducing the solvation ability of H_(2)O,enhancing the competitive coordination of SO_(4)^(2-),essentially eliminating the undesirable side effects of anodes.Hence,symmetric cells can operate stably for 3000 h(51.7-times increase in cycle life),and the full cells can operate stably for 5000 cycles(51.5-times increase in cycle life).This study provides valuable insights into the critical design of weakly solvated Zn^(2+) þand desolvation processes at heterointerfaces.
基金financially supported by the National Natural Science Foundation of China(No.21908085)the Natural Science Foundation of Jiangsu province(No.BK20241950)+3 种基金China Postdoctoral Science Foundation(No.2023M731422)the Open Project of State Key Laboratory of Materials Chemical Engineering(No.SKL-MCE-23B)Hubei Key Laboratory of Processing and Application of Catalytic materials(No.202441204)the Science and Technology Plan School-Enterprise Cooperation Industry-University-Research Forward-looking Project of Zhangjiagang(No.ZKYY2341)
文摘The advanced oxidation process presents a perfect solution for eliminating organic pollutants in water resources,and the local microenvironment and surface state of metal reactive sites are crucial for the selective activation of peroxomonosulfate(PMS),which possibly determines the degradation pathways of organic contaminants.In this study,by virtue of the precursor alternation,we constructed the state-switched dual metal species with the porous carbon fibers through the electrospinning strategy.Impressively,the optimal catalyst,featuring the electron-deficient cobalt surface oxidative state and most abundant oxygen vacancies(Ov)with MnO_(2)within porous carbon fibers,provides abundant mesoporosity,facilitating the diffusion and accommodation of big carbamazepine molecules during the reaction process.Benefiting from the tandem configuration of carbon fiber-encapsulated nanocrystalline species,a p-n heterojunction configuration evidenced by Mott-Schottky analysis induced local built-in electric field(BIEF)between electron-deficient cobalt and Ov-rich MnO_(2)within carbon matrix-mediated interfacial interactions,which optimizes the adsorption and activation of PMS and intermediates,increases the concentration of reactive radicals around the active site,and significantly enhances the degradation performance.As a result,the optimal catalyst could achieve 100%degradation of 20 ppm carbamazepine(CBZ)within only 4 min with a rate constant of 1.099 min^(-1),showcasing a low activation energy(50 kJ mol^(-1)),obviously outperforming the other counterparts.We further demonstrated the generation pathways of active species by activation of PMS mainly including sulfate radical(·SO_(4)^(-)),hydroxyl radical(·OH),superoxide radicals(·O_(2)^(-)),and singlet oxygen(^(1)O_(2)),unveiling their contribution to CBZ degradation.The degradation route of CBZ and toxicity analysis of various intermediates were further evaluated.By anchoring the optimal catalyst onto polyester fiber sponge,the photothermal conversion synergistic monolith floatable catalyst and its easy recovery can be achieved,showing good reproducibility and generalizability in the practical application.
基金supported by the National Natural Science Foundation of China(Nos.52172091,52172295)Defense Industrial Technology Development Program(No.JCKY2023605C002)+4 种基金Frontier Leading Technology Basic Research Major Project of Jiangsu Province(No.BK20232013)the National Key Laboratory on Electromagnetic Environmental Effects and Electro-optical Engineering(No.61422062301)the Opening Project of Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology(No.ASMA202303)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX23_0371)the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory(No.ZHD202305).
文摘Heterointerface engineering based on built-in electric field(BIEF)has been well-received in electromagnetic wave(EMW)absorption.However,the influence of interface size and number of interfaces on the BIEF and interface polarization loss mechanism remains unclear.Here,we designed a ternary dual het-erointerfaces Co@C/SiO_(2)nanocomposite.Experimental and theoretical analyses show that Co@C/SiO_(2)has abundant Mott-Schottky heterointerfaces,and a reasonable increase in the heterointerface area leads to a strong BIEF effect,where the charge accumulates at the interface and subsequently migrates along the direction of the alternating electromagnetic field to promote the dissipation of EMW by polarization loss.However,an excessive number of interfaces leads to many carriers being bound by the interfaces,which is not conducive to forming electron channels.By coordinating the heterointerface states to achieve optimal EMW absorption performance,SZ-3 can accomplish an effective absorption width(EAB)of 5.93 GHz at a thickness of 1.91 mm.This work provides new ideas and methods for BIEF-based heterointerface engineering applied to EMW absorption materials.
基金supported by the Materials/Parts Technology Development Program(No.RS-2024-00456324)funded by the Ministry of Trade,Industry and Energy(MOTIE,Korea)the 2025 Research Fund of Hongik Universitysupported by the MSIT,Korea,under the ITRC support program(IITP-RS-2024-00436248)supervised by the IITP。
文摘Understanding dynamic storage mechanisms and tuning electrode interfaces is vital for designing highperformance potassium-ion battery(KIB)anodes.Despite their high capacities,transition metal telluride(TMTe)anodes often suffer from sluggish K+diffusion and severe volume expansion during cycling,highlighting the need for structurally optimized and interface-engineered architectures.While such strategies have been proven to be effective in lithium-and sodium-ion batteries,their use in TMTe-based KIB anodes remains largely unexplored.In this study,we firstly introduce a heterointerface-engineered three-dimensional microsphere composed of ZnTe nanoparticles and uniformly encapsulated by MXene(denoted MX/ZnTe@NC).Importantly,a built-in electric field(BIEF)is induced at the MXeneZnTe interface due to their work function.This interfacial field modulates the local electronic structure and significantly accelerates K^(+)adsorption and diffusion kinetics,especially under high current densities.First-principles simulations and spectroscopic analyses confirm that the BIEF significantly increases the K~+adsorption strength and lowers the energy barriers for ion transport.Electrochemical analyses reveal that the MX/ZnTe@NC anode delivers a high reversible capacity of 283 mAh g^(-1)after 1000 cycles at 0.5 A g^(-1),with nearly 100%Coulombic efficiency.Even at 10 A g^(-1),the anode retains a capacity of 83 mAh g^(-1),indicating excellent rate performance.Additionally,in-situ and ex-situ characterizations reveal a highly reversible ZnTe conversion mechanism involving dynamic intermediate phases.This study provides mechanistic insight into the structural and chemical evolution during cycling and highlights the synergistic role of interfacial field engineering and three-dimensional heterostructure design in advancing MXene-based KIB anodes.
基金financially supported by the National Natural Science Foundation of China(Grant No.52073106)。
文摘Constructing heterostructures and facilitating surface reconstruction are effective ways to obtain excellent catalysts for the oxygen evolution reaction(OER).Surface reconstruction is a dynamic process that is affected by the built-in electric field of the heterostructure.In this study,P/N co-doped carbon-coated NiCo/Ni-CoO heterostructure was prepared by in situ acid etching,aniline polymerization,and pyrolysis.This method can form a tightly connected heterogeneous interface.It was found that introducing P-O bonds in the carbon shell can increase its work function,thereby enhancing the built-in electric field between the carbon shell and the core catalyst.Detailed characterizations confirm that the P-O bridge at the heterogeneous interface can provide an electron flow highway from the core to the shell.The generated carbon defects generated by P leaching during surface reconstruction also have strong electronabsorbing capacity.These effects promote the conversion of Co^(2+)to Co^(3+),thereby providing more highly active sites.The resulting catalyst shows significantly enhanced activity and stability.This study demonstrates the promoting effect of the built-in electric field on the surface reconstruction of the catalyst and emphasizes the importance of the construction of tightly connected heterogeneous interface,which is instructive for the design of excellent OER catalysts.
基金supported by the National Key Research and Development Program of China(No.2022YFB3807100)National Natural Science Foundation of China(No.22205182)+2 种基金the National Science Fund for Distinguished Young Scholars(No.52025034)Basic and Applied Basic Research Foundation of Guangdong(No.2024A1515011516)supported by the Innovation Team of the Shaanxi Sanqin Scholars.
文摘Built-in electric fields(BIEF),engineered via space charge manipulation,represent an effective strategy for enhance electromagnetic loss.However,single BIEF fail to reconcile the impedance matching and strong electromagnetic attenuation across broad frequency spectra,resulting in limited effective absorption bandwidth(EAB).To address this,dual-BIEF are constructed utilizing an asymmetric gradient electric field structure and multi-polarization center coordination to achieve high-efficiency broad EAB.Herein,heterostructure Ni-Co bimetallic nanocomposites(Ni_(0.5)Co_(0.5)@NiCoO_(2)/NCP)are constructed via Ni-Co-based nanocomposites(NiCoO_(2)and Ni_(0.5)Co_(0.5))integrated with nitrogen-doped nanoporous carbon(NCP).This configuration forms dual heterojunctions the NCP-NiCoO_(2)-semiconductor heterojunction and the NiCoO_(2)-Ni_(0.5)Co_(0.5)Mott-Schottky heterojunction—forming the dual-BIEF system.The superposed dual-BIEF drives charge-pumping dynamics facilitating oriented transfer and transition of charges that strengthen interfacial polarization and reduced relaxation times.Theoretical calculations confirm this system simultaneously modulates conductivity,intensifies polarization relaxation,promotes charge separation,and optimizes dipole distribution.Dielectric loss from semiconductor junctions dominates the low-frequency regime,while conductive loss via Mott-Schottky junctions prevails at high frequencies.Thus,the Ni_(0.5)Co_(0.5)@NiCoO_(2)/NCP achieves excellent microwave absorption with a remarkable minimum reflection loss of51.5 dB,and an EAB of 6.4 GHz at 2.8 mm thickness.This work establishes a dual-BIEF strategy for effectively engineering high-performance electromagnetic wave absorption materials.
基金supported by the National Natural Science Foundation of China(22262010,22062005,22165005,U20A20128)Guangxi Science and Technology Fund for Distinguished HighTalent Introduction Program(AC22035091)Guangxi Science Fund for Distinguished Young Scholars(2019GXNSFFA245016)。
文摘Rational design of defected carbons adjacent to nitrogen(N)dopants is a fascinating but challenging approach for enhancing the catalytic performance of N-doped carbon.Meanwhile,the combined effect of heteroatom doping and defect engineering can efficiently increase the oxygen reduction reaction(ORR)ability of inactive carbons through charge redistribution.Herein,we report that an enhanced built-in electric field caused by the combined effect of N-doping and carbon defects in the twodimensional(2D)mesoporous N-doped carbon nano flakes(NCNF)is a promising technique for improving ORR performance.As a result,the NCNF exhibits more promising ORR activity than Pt/C and similar performance with reported robust catalysts.Comprehensive experimental and theoretical investigations suggest that topologically defected carbon adjacent to the graphitic valley nitrogen is a real active site,rendering optimal energy for the adsorption of ORR intermediates and lowering the total energy barrier for ORR.Also,NCNF-based Zn-air batteries exhibited an excellent power density and specific capacity of~121.10 mW cm^(-2)and~679.86 mA h g_(Zn)^(-1),respectively.This study not only offers new insights into defected carbons with graphitic valley N for ORR but also proposes novel catalyst design principles and provides a solid grasp of the built-in electric field effect on the ORR performance of defective catalysts.
基金the financial support from the National Natural Science Foundation of China(NSFC,Nos.U23A20579,U1904190,52272243)the Natural Science Foundation of Henan Province(No.242300421467)+3 种基金the Program for Science and Technology Innovation Talents in Universities of Henan Province(No.22HASTIT005)Key Scientific Research Projects in Higher Education Institutions of Henan Province(Nos.24A430047,24A430029)China Postdoctoral Science Foundation(No.2023M741083)Research Foundation for Talented Scholars(No.21010744)。
文摘Transition metal selenides(TMS)demonstrate exceptional catalytic activity in the oxygen evolution reaction(OER),yet their performance is hindered by surface reconstruction under OER conditions,particularly at high current densities.This study reveals that embedding Co_(0.85)Se nanoparticles into the interlayer spacing of MXene-Ti_(3)C_(2)effectively suppresses surface reconstruction during OER.This configuration establishes a Schottky heterojunction with an intrinsic built-in electric field(BEF)between Co_(0.85)Se and Ti_(3)C_(2),which enhances charge redistribution and accelerates electron transport.Consequently,the Co_(0.85)Se@Ti_(3)C_(2)composite exhibits outstanding OER performance,achieving low overpotentials(230 m V at 100 m A/cm^(2),376 m V at 1000 m A/cm^(2),417 m V at 1500 m A/cm^(2))and exceptional durability(200 h at200 m A/cm^(2)).In-situ XRD/Raman characterization verifies that the encapsulated Co_(0.85)Se within Ti_(3)C_(2)inhibits CoOOH formation on the surface during OER.Both experimental and theoretical investigations indicate that the heterojunction's superhydrophilicity/superaerophobicity,synergized with BEF-regulated oxygen intermediate adsorption/desorption,collectively enhance catalytic efficiency of Co_(0.85)Se@Ti_(3)C_(2).This strategy of spatially confining chalcogenide catalysts to prevent structural degradation while leveraging interfacial electric fields presents a rational approach for developing durable electrocatalysts in highcurrent densities water electrolysis.
基金financially supported by the Science and Technology Commission of Shanghai Municipality(No.23HC1400302)the National Natural Science Foundation of China(Nos.22162021 and 21862013)the Natural Science Foundation of Ningxia Province(Nos.2021AAC03057 and 2023AAC03015).
文摘The built-in electric field(BIEF)aroused by the variation in charge distribution between the surface and bulk phase of carbon nitride can improve carrier dynamics.Herein,phosphorus(P)and benzene ringdoped C_(3)N_(5)nanosheets(PPCN_(2))were synthesized by a facile method and demonstrated excellent performance in the photocatalytic degradation of antibiotics.Benzene ring replaced the triazine part of the heptazine unit,expanding the π-conjugated structure of the system,promoting electron delocalization,and enhancing the light-absorbing property.P doping led to the creation of an additional donor state within the P 2p band,facilitating the charge separation and lengthening the transport distance of electron-hole pairs.Additionally,the intermediate state gap created in the Urbach tail further strengthened photon absorption and improved effective electron capture.XPS with Ar ion etching at different depths verified the significant potential difference and large dipole moment caused by different doping levels of surface and bulk phase,resulting in a strong BIEF inside the PPCN_(2).KPFM,SPV,and DFT calculations confirmed the strong BIEF in PPCN_(2).EPR,rotating disk electrode(RRDE)and in situ infrared drift(DRIFT)spectroscopy confirmed the reactive oxygen species and the two-step one-electron reduction reaction mechanism during the photodegradation process.This work provides a new perspective for the study of improving the photocatalytic performance of C_(3)N_(5)by inducing the BIEF which arose from the differences in electronic structure and charge distribution on the surface and bulk phase caused by molecular doping.
基金financially supported by the National Natural Science Foundation of China(Nos.52271034,52301058 and 52471042)the National MCF Energy R&D Program of China(No.2018YFE0306102)+1 种基金the China Postdoctoral Science Foundation(No.2023M732183)the Postdoctoral Fellowship Program of CPSF(No.GZB20230399).
文摘To develop a melting-based larger-scale fabrication process for oxide dispersion strengthened(ODS)steel,this study proposed a method of zone melting with built-in precursor powder(ZMPP),followed by hot forging and aging treatments.A 50 kg ingot was successfully prepared,highlighting the scalability of this innovative process.Microstructural analysis revealed a predominantly lath martensite matrix with a small amount of ferrite in the hot-forged ODS steel,without oxide particle aggregation.Aging at 750℃ resulted in the formation of sub-micron-sized Cr_(23)C_(6) particles at grain boundaries and martensitic lath interfaces,accompanied by a high-density(7.64×1023 m^(-3))nano-scale(~6 nm)Y-Si-O complex oxides after 25 h.Additionally,the hot-forged sample exhibited a high yield strength(871 MPa)but limited ductility(5.0%).Aging treatments led to an increase in ductility but a decrease in yield strength.Notably,prolonged aging maintained the strength level of steels while enhancing ductility,with a 23.3% total elongation observed after 25 h.The novel ZMPP method,preparing high-quality ODS steels with uniform microstructure and good mechanical properties,provided a new avenue for large-scale production of ODS steels.
基金supported by the National Natural Science Foundation of China(U24A20550,52273264 and 52470073)the Key Project of the Heilongjiang Provincial Natural Science Foundation(ZD2024B001)Outstanding Youth Fund of Heilongjiang Province(JQ2022E005).
文摘Designing a heterogeneous interface to improve the kinetics of electrocatalysts represents an effective yet challenging approach for enhancing the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).Herein,a simple MOF-assisted etching-pyrolysis strategy is proposed to fabricate an advanced Mott-Schottky(M–S)electrocatalyst composed of Co/CeO_(2)hetero-nanoparticles embedded within N-doped hollow carbon nanoboxes(H-Co/CeO_(2)@NCBs).Notably,the interfacial Co–O–Ce bond bridging productively facilitates the electron transfer and modulates the charge distribution of the active center,thereby contributing to the ORR/OER kinetics.As expected,the optimal M–S H-Co/CeO_(2)@NCBs catalyst exhibits promising bifunctional electrocatalytic activity with a small potential discrepancy of 0.65 V.Theoretical calculations reveal that the built-in electric field in the M–S heterojunction promotes electron transfer in oxygen electrocatalysis and the interfacial bridge-induced electron redistribution optimizes the adsorption/desorption of the oxygen intermediates,leading to reduced activation energy for the bifunctional ORR/OER reactions.Importantly,H-Co/CeO_(2)@NCBs-assembled Zn-air battery(ZAB)delivers high power density(179.8 mW cm^(−2))and long-term stability(400 h).Furthermore,the assembled flexible solid-state ZAB with H-Co/CeO_(2)@NCBs cathode also exhibits excellent charge–discharge reversibility and flexibility at various bending angles.This work provides a novel perspective on developing efficient and stable M–S bifunctional oxygen electrocatalysts.
基金supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2015023)National Natural Science Foundation of China(81471784,51802115)+3 种基金Natural Science Foundation of Beijing(2172058)Natural Science Foundation of Shandong Province(ZR2018BEM010,ZR2019YQ21)Major Program of Shandong Province Natural Science Foundation(ZR2018ZC0843)Scientific and Technology Project of University of Jinan(XKY1923)~~
文摘Rapid technological development and population growth are responsible for a series of imminent environmental problems and an ineluctable energy crisis.The application of semiconductor nanomaterials in photocatalysis or photoelectrocatalysis(PEC)for either the degradation of contaminants in the environment or the generation of hydrogen as clean fuel is an effective approach to alleviate these problems.However,the efficiency of such processes remains suboptimal for real applications.Reasonable construction of a built-in electric field is considered to efficiently enhance carrier separation and reduce carrier recombination to improve catalytic performance.In the past decade,as a new method to enhance the built-in electric field,the piezoelectric effect from piezoelectric materials has been extensively studied.In this review,we provide an overview of the properties of piezoelectric materials and the mechanisms of piezoelectricity and ferroelectricity for a built-in electric field.Then,piezoelectric and ferroelectric polarization regulated built-in electric fields that mediate catalysis are discussed.Furthermore,the applications of piezoelectric semiconductor materials are also highlighted,including degradation of pollutants,bacteria disinfection,water splitting for H2 generation,and organic synthesis.We conclude by discussing the challenges in the field and the exciting opportunities to further improve piezo-catalytic efficiency.
基金supported by the National Natural Science Foundation of China(No.22269010,52231007,12327804,T2321003,22088101)the Jiangxi Provincial Natural Science Foundation(No.20224BAB214021)+1 种基金the Major Research Program of Jingdezhen Ceramic Industry(No.2023ZDGG002)the Ministry of Science and Technology of China(973 Project No.2021YFA1200600).
文摘The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not monotonous.In this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky junctions.By skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching thickness.The successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW absorption.We detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal interfaces.The achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 mm.Radar cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth technology.This work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities.
文摘An electron transporting material of TFTTP (4-(5-hexylthiophene-2-yl)-2,6-bis(5-trifluoromethyl)thiophen-2-yl)pyridine) was investigated as a cathode buffer layer to enhance the power efficiency of organic solar cells (OSCs) based on subphthalocyanine and C60. The overall power conversion efficiency was increased by a factor of 1.31 by inserting the TFTTP interfacial layer between the active layer and metallic cathode. The inner mechanism responsible for the performance enhancement of OSCs was systematically studied with the simulation of dark diode behavior and optical field distribution inside the devices as well as the characterization of device photocurrent. The results showed that the TFTTP layer could significantly increase the built-in potential in the devices, leading to the enhanced dissociation of charge transfer excitons. In addition, by using TFTTP as the buffer layer, a better Ohmic contact at C60/metal interface was formed, facilitating more efficient free charge carrier collection.