The immobilization of catalysts on supporting substrates for the removal of organic pollutants is a crucial strategy for mitigating catalyst loss during wastewater treatment.This study presented a rapid and cost-effec...The immobilization of catalysts on supporting substrates for the removal of organic pollutants is a crucial strategy for mitigating catalyst loss during wastewater treatment.This study presented a rapid and cost-effective direct heating method for synthesizing MnO2 nanoflowers on coil substrates for the removal of organic pollutants.Traditional methods often require high power,expensive equipment,and long synthesis times.In contrast,the direct heating approach successfully synthesized MnO2 nanoflowers in just 10 min with a heating power of approximately 40 W·h after the heating power and duration were optimized.These nanoflowers effectively degraded 99%Rhodamine B in 60 min with consistent repeatability.The catalytic mechanisms are attributed to crystal defects in MnO2,which generate electrons to produce H2O2.Mn2+ions in the acidic solution further dissociate H2O2 molecules into hydroxyl radicals(·OH).The high efficiency of this synthesis method and the excellent reusability of MnO2 nanoflowers highlight their potential as a promising solution for the development of supporting MnO2 catalysts for organic dye removal applications.展开更多
Pure TiO_(2)and copper-modified titania(Cu/TiO_(2))nanoparticles were synthesized through sol gel combined with the pyrolysis method for the removal of Congo red(CR)in wastewater treatment.Surface morphology and struc...Pure TiO_(2)and copper-modified titania(Cu/TiO_(2))nanoparticles were synthesized through sol gel combined with the pyrolysis method for the removal of Congo red(CR)in wastewater treatment.Surface morphology and structural evaluation utilized XRD,TEM,Raman,FTIR and BET techniques.Cu/TiO_(2)showed rich defects and a higher specific surface area than that of TiO_(2).The 1Cu/TiO_(2)(molar ratio Cu/TiO_(2)of 1/100)showed the best performance to adsorption of CR solution at different reaction conditions(contact duration,CR concentration,adsorbent dose,temperature,and initial pH).Adsorption kinetics and equilibrium isotherms were well-described with a pseudo-second-order kinetics and Freundlich model,respectively.The negative ΔG indicates stable adsorption of CR on the Cu/TiO_(2)surface.The adsorption efficiency only decreases by 6%after 5 cycles of adsorption regeneration.The successful synthesis of Cu/TiO_(2)offers a new possibility to address the problems related to CR dye from aqueous solutions.展开更多
The p-block metal(In,Sn,Bi,etc.)-based electrocatalysts have exhibited excellent activity in the electrocatalytic CO_(2)reduction(ECR)to formate.However,the rapid decrease in catalytic activity caused by catalyst reco...The p-block metal(In,Sn,Bi,etc.)-based electrocatalysts have exhibited excellent activity in the electrocatalytic CO_(2)reduction(ECR)to formate.However,the rapid decrease in catalytic activity caused by catalyst reconstruction and agglomeration under ECR conditions significantly restricts their practical applications.Herein,we developed a sulfur anchoring strategy to stabilize the high-density sub-3 nm In_(2)S_(3)nanoparticles on sulfur-doped porous carbon substrates(i-In_(2)S_(3)/S-C)for formate production.Systematic characterizations evidenced that the as-prepared catalyst exhibited a strong metal sulfide-support interaction(MSSI),which effectively regulated the electronic states of In_(2)S_(3),achieving a high formate Faradaic efficiency of 91%at−0.95 V vs.RHE.More importantly,the sulfur anchoring effectively immobilized the sub-3 nm In_(2)S_(3)nanoparticles to prevent them from agglomeration.It enabled the catalysts to exhibit much higher durability than the In_(2)S_(3)samples without sulfur anchoring,demonstrating that the strong MSSI and fast charge transfer on the catalytic interface could significantly promote the structural stability of In_(2)S_(3)catalysts.These results provide a viable approach for developing efficient and stable electrocatalysts for CO_(2)reduction.展开更多
Synergistic interplays involving multiple active centers originating from TiO2 nanotube layers(TNT)and ruthenium(Ru)species comprising of both single atoms(SAs)and nanoparticles(NPs)augment the alkaline hydrogen evolu...Synergistic interplays involving multiple active centers originating from TiO2 nanotube layers(TNT)and ruthenium(Ru)species comprising of both single atoms(SAs)and nanoparticles(NPs)augment the alkaline hydrogen evolution reaction(HER)by enhancing Volmer kinetics from rapid water dissociation and improving Tafel kinetics from efficient H*desorption.Atomic layer deposition of Ru with 50 process cycles results in a mixture of Ru SAs and 2.8-0.4 nm NPs present on TNT layers,and it emerges with the highest HER activity among all the electrodes synthesized.A detailed study of the Ti and Ru species using different high-resolution techniques confirmed the presence of Ti^(3+)states and the coexistence of Ru SAs and NPs.With insights from literature,the role of Ti^(3+),appropriate work functions of TNT layers and Ru,and the synergistic effect of Ru SAs and Ru NPs in improving the performance of alkaline HER were elaborated and justified.The aforementioned characteristics led to a remarkable performance by having 9mV onset potentials and 33 mV dec^(-1) of Tafel slopes and a higher turnover frequency of 1.72 H2 s^(-1) at 30 mV.Besides,a notable stability from 28 h staircase chronopotentiometric measurements for TNT@Ru surpasses TNT@Pt in comparison.展开更多
Photoheranostics have emerged as a promising tool for cancer theranostics owing to their real-time feedback on treatment and their precise diagnosis.Among them,how to improve the photothermal conversion efficiency(PCE...Photoheranostics have emerged as a promising tool for cancer theranostics owing to their real-time feedback on treatment and their precise diagnosis.Among them,how to improve the photothermal conversion efficiency(PCE)of phototheranostic agents(PTAs)is the key factor for phototheranostic systems.Herein,we provided an efficient method to improve PCE and constructed a biocompatible nano-material ICR-Qu@NH_(2)-Fe_(3)O_(4)@PEG(QNFP)by combing near-infrared second region(NIR-Ⅱ)molecular dye ICR-Qu and amino-modified magnetic nanoparticles and then encapsulated by DSPE-m PEG2000.QNFP exhibited excellent performance for photothermal therapy with a high PCE of 95.6%.Both in vitro and in vivo experiments indicated that QNFP could inhibit the growth of tumors under laser irradiation with low toxicity and realized real-time NIR-Ⅱfiuorescent imaging of tumors.In general,we realized a simple but efficient method to improve the PCE of NIR-Ⅱmolecular dye without reduce its quantum yield,which is an ideal choice for cancer diagnosis and treatment.展开更多
Changes in solution chemistry and transport conditions can lead to the release of deposited MnO2 nanoparticles from a solid interface,allowing them to re-enter the aqueous environment.Understanding the release behavio...Changes in solution chemistry and transport conditions can lead to the release of deposited MnO2 nanoparticles from a solid interface,allowing them to re-enter the aqueous environment.Understanding the release behavior of Mn02 nanoparticles from naturally occurring surfaces is critical for better prediction of the transport potential and environmental fate of Mn02 nanoparticles.In this study,the release of Mn02 nanoparticles was investigated using a quartz crystal microbalance with dissipation monitoring(QCM-D),and different environmental surface types,solution pH values and representative macromolecular organics were considered.Mn02 nanoparticles were first deposited on crystal sensors at elevated NaN03 concentrations before being rinsed with double-deionized water to induce their remobilization.The results reveal that the release rate of Mn02 depends on the surface type,in the decreasing order:SiO2>Fe304>Al2 O3,resulting from electrostatic interactions between the surface and particles.Moreover,differences in solution pH can lead to variance in the release behavior of Mn02 nanoparticles.The release rate from surfaces was significantly higher at pH 9.8 that at 4.5,indicating that alkaline conditions were more favorable for the mobilization of Mn02 in the aquatic environment.In the presence of macromolecular organics,bovine serum albumin(BSA)can inhibit the release of Mn02 from the surfaces due to attractive forces.In presence of humic acid(HA)and sodium alginate(SA),the Mn02 nanoparticles were more likely to be mobile,which may be associated with a large repulsive barrier imparted by steric effects.展开更多
In this study, the in-situ synthesized ZrB_(2) nanoparticles and rare earth Sc were introduced to enhance the strength and ductility of 7N01 aluminum alloy, via the generation of high-melting and uniform nanodispersoi...In this study, the in-situ synthesized ZrB_(2) nanoparticles and rare earth Sc were introduced to enhance the strength and ductility of 7N01 aluminum alloy, via the generation of high-melting and uniform nanodispersoids. The microstructure and mechanical property evolution of the prepared composites and the interaction between ZrB_(2) and Sc were studied in detail. The microstructure investigation shows that the introduction of rare earth scandium(Sc) can promote the distribution of ZrB_(2) nanoparticles, by improving their wettability to the Al melt. Meanwhile, the addition of rare earth Sc also modifies the coarse Al Zn Mg Mn Fe precipitated phases, refines the matrix grains and generates high-melting Al_3(Sc,Zr)/Al_3Sc nanodispersoids. Tensile tests of the composites show that with the combinatorial introduction of ZrB_(2) and Sc, the strength and ductility of the composites are improved simultaneously compared with the corresponding 7N01 alloy, ZrB_(2) /7N01 composite and Sc/7N01 alloy. And the optimum contents of ZrB_(2) and Sc are 3 wt% and 0.2 wt% in this study. The yield strength, ultimate strength and elongation of(3 wt% ZrB_(2) +0.2 wt% Sc)/7N01 composite are 477 MPa, 506 MPa and 9.8%, increased about 18.1%, 12.2%and 38% compared to 7N01 alloy. Furthermore, the cooperation strengthening mechanisms of ZrB_(2) and Sc are also discussed.展开更多
Molecular dynamics(MD)simulations are employed to delve into the multifaceted effects of TiB_(2) nanoparticles on the intricate grain refinement mechanism,microstructural evolution,and tensile performance of Inconel 7...Molecular dynamics(MD)simulations are employed to delve into the multifaceted effects of TiB_(2) nanoparticles on the intricate grain refinement mechanism,microstructural evolution,and tensile performance of Inconel 718 superalloys during the rapid directional solidification.Specifically,the study focuses on elucidating the role of TiB2 nanoparticles in augmenting the nucleation rate during the rapid directional solidification process of Ni_(60)Cr_(21)Fe_(19) alloy system.Furthermore,subsequent tensile simulations are conducted to comprehensively evaluate the anisotropic behavior of tensile properties within the solidified microstructures.The MD results reveal that the incorporation of TiB₂nanoparticles during the rapid directional solidification of the Ni_(60)Cr_(21)Fe_(19) significantly enhances the average nucleation rate,escalating it from 1.27×10^(34)m^(-3)·s^(-1)to 2.55×10^(34)m^(-3)·s^(-1).Notably,within the face centered cube(FCC)structure,Ni atoms exhibit pronounced compositional segregation,and the solidified alloy maintains an exceptionally high dislocation density reaching up to 10^(16)m^(-2).Crucially,the rapid directional solidification process imparts a distinct microstructural anisotropy,leading to a notable disparity in tensile strength.Specifically,the tensile strength along the solidification direction is markedly superior to that perpendicular to it.This disparity arises from different deformation mechanisms under varying loading orientations.Tensile stress perpendicular to the solidification direction encourages the formation of smooth and organized mechanical twins.These twins act as slip planes,enhancing dislocation mobility and thereby improving stress relaxation and dispersion.Moreover,the results underscore the profound strengthening effect of TiB_(2) nanoparticles,particularly in enhancing the tensile strength along the rapid directional solidification direction.展开更多
Foam stability tests were performed using sodium dodecyl sulfate(SDS)surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations,and the half-life of CO_(2) foam was measured.The mechani...Foam stability tests were performed using sodium dodecyl sulfate(SDS)surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations,and the half-life of CO_(2) foam was measured.The mechanism of foam stability reduction in the presence of asphaltene was analyzed by scanning electron microscope(SEM),UV adsorption spectrophotometric concentration measurement and Zeta potential measurement.When the mass ratio of synthetic oil to foam-formation suspension was 1:9 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 751 s to 239 s,and the half-life of SDS/silica-stabilized foams decreased from 912 s to 298 s.When the mass ratio of synthetic oil to foam-formation suspension was 2:8 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 526 s to 171 s,and the half-life of SDS/silica-stabilized foams decreased from 660 s to 205 s.In addition,due to asphaltene-SDS/silica interaction in the aqueous phase,the absolute value of Zeta potential decreases,and the surface charges of particles reduce,leading to the reduction of repulsive forces between two interfaces of thin liquid film,which in turn,damages the foam stability.展开更多
Porous silica nano-flowers(KCC-1)immobilized Pt-Pd alloy NPs(Pt-Pd/KCC-1)with different mass ratios of Pd and Pt were successfully prepared by a facile in situ one-step reduction,using hydrazinium hydroxide as a reduc...Porous silica nano-flowers(KCC-1)immobilized Pt-Pd alloy NPs(Pt-Pd/KCC-1)with different mass ratios of Pd and Pt were successfully prepared by a facile in situ one-step reduction,using hydrazinium hydroxide as a reducing agent.The as-synthesized silica nanospheres possess radial fibers with a distance of 15 nm,exhibiting a high specific surface area(443.56 m^(2)·g^(-1)).Meanwhile,the obtained Pt-Pd alloy NPs are uniformly dispersed on the silica surface with a metallic particle size of 4-6 nm,which exist as metallic Pd and Pt on the surface of monodisperse KCC-1,showing the transfer of electrons from Pd to Pt.The as-synthesized 2.5%Pt-2.5%Pd/KCC-1 exhibited excellent catalytic activity and stability for the continuous dehydrogenation of 2-methoxycyclohexanol to prepare guaiacol.Compared with Pt or Pd single metal supported catalysts,the obtained 2.5%Pt-2.5%Pd/KCC-1 shows 97.2%conversion rate of 2-methoxycyclohexanol and 76.8%selectivity for guaiacol,which attributed to the significant synergistic effect of bimetallic Pt-Pd alloy NPs.Furthermore,turn over frequency value of the obtained 2.5%Pt-2.5%Pd/KCC-1 NPs achieved 4.36 s^(-1),showing higher catalytic efficiency than other two monometallic catalysts.Reaction pathways of dehydro-aromatization of 2-methoxycyclohexanol over the obtained catalyst are proposed.Consequently,the obtained 2.5%Pt-2.5%Pd/KCC-1 NPs prove their potential in the dehydrogenation of 2-methoxycyclohexanol,while the kinetics and mechanistic study of the dehydrogenation reaction over the catalyst in a continuous fixed-bed reactor may provide valuable information for the development of green,outstanding and powerful synthetic pathway of guaiacol.展开更多
The influence of Mo and ZrO_(2)nanoparticles addition on the interfacial properties and shear strength of Sn58Bi solder joint was investigated.The interfacial microstructures of Sn58Bi/Cu,Sn58Bi+Mo/Cu and Sn58Bi+ZrO_(...The influence of Mo and ZrO_(2)nanoparticles addition on the interfacial properties and shear strength of Sn58Bi solder joint was investigated.The interfacial microstructures of Sn58Bi/Cu,Sn58Bi+Mo/Cu and Sn58Bi+ZrO_(2)/Cu solder joints were analysed using a scanning electron microscope(SEM)coupled with energy dispersive X-ray(EDX)and the X-ray diffraction(XRD).Intermetallic compounds(IMCs)of MoSn_(2)are detected in the Sn58Bi+Mo/Cu solder joint,while SnZr,Zr_(5)Sn_(3),ZrCu and ZrSn_(2)are detected in Sn58Bi+ZrO_(2)/Cu solder joint.IMC layers for both composite solders comprise of Cu_(6)Sn_(5) and Cu_(3)Sn.The SEM images of these layers were used to measure the IMC layer’s thickness.The average IMC layer’s thickness is 1.4431μm for Sn58Bi+Mo/Cu and 0.9112μm for Sn58Bi+ZrO_(2)/Cu solder joints.Shear strength of the solder joints was investigated via the single shear lap test method.The average maximum load and shear stress of the Sn58Bi+Mo/Cu and Sn58Bi+ZrO_(2)/Cu solder joints are increased by 33%and 69%,respectively,as compared to those of the Sn58Bi/Cu solder joint.By comparing both composite solder joints,the latter prevails better as adding smaller sized ZrO_(2)nanoparticles improves the interfacial properties granting a stronger solder joint.展开更多
Single-chain nanoparticles represent an emerging class of nanomaterials designed to mimic protein's folding paradigm.Intrachain covalent crosslinking toward the formation of single-chain nanoparticles encounters c...Single-chain nanoparticles represent an emerging class of nanomaterials designed to mimic protein's folding paradigm.Intrachain covalent crosslinking toward the formation of single-chain nanoparticles encounters complex energy landscapes,leading to the potential occurrence of misfolding issues.While noncovalent crosslinking can circumvent this issue,the resulting single-chain nanoparticles exhibit lower structural stability compared to their covalently crosslinked counterparts.In this study,we present a novel approach for the synthesis of single-chain nanoparticles,achieved through the combination of non-covalent and covalent intramolecular crosslinking.Cyanostilbenes grafted onto the linear polymer form intrachain non-covalent stacks aided by hydrogen bonds,leading to the formation of non-covalently crosslinked single-chain nanoparticles.These nanoparticles undergo conversion to covalently crosslinked nanostructures through subsequent photo-irradiation using[2+2]photocycloaddition,a process facilitated by the supramolecular confinement effect.Consequently,the resulting single-chain nanoparticles demonstrate both intrachain folding efficiency and substantial stability,offering significant potential for advancing applications across diverse fields.展开更多
Cerium-doped zirconium-based NH_(2)-UiO-66 nanoparticles were synthesized in ionic liquid 1-butyl-3-methylimidazolium acetate at room temperature.The crystal structure and morphology were studied using X-ray diffracti...Cerium-doped zirconium-based NH_(2)-UiO-66 nanoparticles were synthesized in ionic liquid 1-butyl-3-methylimidazolium acetate at room temperature.The crystal structure and morphology were studied using X-ray diffraction,infrared spectroscopy,scanning electron microscopy and transmission electron microscopy.The valence state and distribution of elements in the obtained materials were examined using X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy.Catalytic performance studies show that the cerium-doped NH_(2)-UiO-66 exhibits improved catalytic efficiency in the cycloaddition reaction of 1,2-butylene oxide and carbon dioxide than pure NH_(2)-UiO-66.Studies on the photoelectric properties indicate that the cerium-doped NH_(2)-UiO-66 catalyst possesses strong photocurrent response,low interfacial charge transfer resistance,narrow band gap,and low flat band potential.This work provides a new approach of synthesizing high-performance catalyst for photocatalytic CO_(2) cycloaddition.展开更多
Lithium (Li)-CO_(2) battery is rising as an attractive energy-storage system with the competence of CO_(2) conversion/fixation. However, its practical development is seriously hindered by the high overpotential. Herei...Lithium (Li)-CO_(2) battery is rising as an attractive energy-storage system with the competence of CO_(2) conversion/fixation. However, its practical development is seriously hindered by the high overpotential. Herein, a rational design on a highly catalytic Li-CO_(2) battery electrode built by graphdiyne powder as a multi-functional laminar scaffold with anchored highly dispersed Ru nanoparticles is explored. The strong interaction between the abundant acetylenic bond sites of graphdiyne scaffold and Ru nanoparticles can effectively promote the electrochemical progress and reduce the voltage polarization. The unique channels architecture of the cathodic catalyst with enough space not only accelerates CO_(2) diffusion and electrons/Li+ transport, but also allows a large amount of accommodation for discharged product (Li2CO3) to assure an advanced capacity. The corresponding Li-CO_(2) battery displays an advanced discharged capacity of 15,030 mAh/g at 500 mA/g, great capacity retention of 8873 mAh/g at 2 A/g, high coulombic efficiency of 97.6% at 500 mA/g and superior life span for 120 cycles with voltage gap of 1.67 V under a restricted capacity of 1000 mAh/g at 500 mA/g. Ex/in-situ studies prove that synergy between Ru nanoparticles and acetylene bonds of GDY can boost the round-trip CO_(2)RR and CO_(2)ER kinetics.展开更多
Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the pa...Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the electrode.Building upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral electrolyte.Employing CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow cell.Furthermore,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)products.This advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.展开更多
Developing low-loading single-atom catalysts with superior catalytic activity and selectivity in formaldehyde(HCHO)oxidation at room temperature remains challenging.Herein,ZrO_(2)nanoparticles coupled low-loading Ir s...Developing low-loading single-atom catalysts with superior catalytic activity and selectivity in formaldehyde(HCHO)oxidation at room temperature remains challenging.Herein,ZrO_(2)nanoparticles coupled low-loading Ir single atoms in N-doped carbon(Ir_(1)-N-C/ZrO_(2))was prepared.The optimal Ir_(1)-N-C/ZrO_(2)with 0.25 wt%Ir loading delivers the high HCHO removal and conversion efficiency(>95%)at 20℃,which is higher than that over Ir_(1)-N-C with the same Ir loading.The specific rate can reach 1285.6 mmol gIr^(-1)h^(-1),surpassing the Ir based catalysts reported to date.Density functional theory calculation results and electron spin resonance spectra indicate that the introduction of Zr O_(2)nanoparticles modulate the electronic structure of the Ir single atoms,promoting O_(2)activation to·O_(2)^(–).Moreover,the Ir-C-Zr channel is favorable for the dissociation of·O_(2)^(–)to active oxygen atom(*O),and further accelerates the transformation of HCHO and intermediates(dioxymethylene and formates)to CO_(2)and H_(2)O.This work provides a facile strategy to design low-loading single-atom catalysts with high catalytic activity toward HCHO oxidation.展开更多
Advanced photovoltaics,such as ultra-flexible perovskite solar cells(UF-PSCs),which are known for their lightweight design and high power-to-mass ratio,have been a long-standing goal that we,as humans,have continuousl...Advanced photovoltaics,such as ultra-flexible perovskite solar cells(UF-PSCs),which are known for their lightweight design and high power-to-mass ratio,have been a long-standing goal that we,as humans,have continuously pursued.Unlike normal PSCs fabricated on rigid substrates,producing high-efficiency UF-PSCs remains a challenge due to the difficulty in achieving full coverage and minimizing defects of metal halide perovskite(MHP)films.In this study,we utilized Al_(2)O_(3) nanoparticles(NPs)as an inorganic surface modifier to enhance the wettability and reduce the roughness of poly-bis(4-phenyl)(2,4,6-trimethylphenyl)amine simultaneously.This approach proves essentials in fabricating UF-PSCs,enabling the deposition of uniform and dense MHP films with full coverage and fewer defects.We systematically investigated the effect of Al_(2)O_(3) NPs on film formation,combining simulation with experiments.Our strategy not only significantly increases the power conversion efficiency(PCE)from 11.96%to 16.33%,but also promotes reproducibility by effectively addressing the short circuit issue commonly encountered in UF-PSCs.Additionally,our UF-PSCs demonstrates good mechanical stability,maintaining 98.6%and 79.0%of their initial PCEs after 10,000 bending cycles with radii of 1.0 and 0.5 mm,respectively.展开更多
Solid oxide electrolysis cells(SOECs),displaying high current density and energy efficiency,have been proven to be an effective technique to electrochemically reduce CO_(2)into CO.However,the insufficiency of cathode ...Solid oxide electrolysis cells(SOECs),displaying high current density and energy efficiency,have been proven to be an effective technique to electrochemically reduce CO_(2)into CO.However,the insufficiency of cathode activity and stability is a tricky problem to be addressed for SOECs.Hence,it is urgent to develop suitable cathode materials with excellent catalytic activity and stability for further practical application of SOECs.Herein,a reduced perovskite oxide,Pr_(0.35)Sr_(0.6)Fe_(0.7)Cu_(0.2)Mo_(0.1)O_(3-δ)(PSFCM0.35),is developed as SOECs cathode to electrolyze CO_(2).After reduction in 10%H_(2)/Ar,Cu and Fe nanoparticles are exsolved from the PSFCM0.35 lattice,resulting in a phase transformation from cubic perovskite to Ruddlesden-Popper(RP)perovskite with more oxygen vacancies.The exsolved metal nanoparticles are tightly attached to the perovskite substrate and afford more active sites to accelerate CO_(2)adsorption and dissociation on the cathode surface.The significantly strengthened CO_(2)adsorption capacity obtained after reduction is demonstrated by in situ Fourier transform-infrared(FT-IR)spectra.Symmetric cells with the reduced PSFCM0.35(R-PSFCM0.35)electrode exhibit a low polarization resistance of 0.43Ωcm^(2)at 850℃.Single electrolysis cells with the R-PSFCM0.35 cathode display an outstanding current density of 2947 mA cm^(-2)at 850℃and 1.6 V.In addition,the catalytic stability of the R-PSFCM0.35 cathode is also proved by operating at 800℃with an applied constant current density of 600 mA cm^(-2)for 100 h.展开更多
Modulating electronic structures of single-atom metal cocatalysts is vital for highly active photoreduction of CO_(2),and it's especially challenging to develop a facile method to modify the dispersion of atomical...Modulating electronic structures of single-atom metal cocatalysts is vital for highly active photoreduction of CO_(2),and it's especially challenging to develop a facile method to modify the dispersion of atomical photocatalytic sites.We herein report an ion-loading pyrolysis route to in-situ anchor Pd single atoms as well as twinned Pd nanoparticles on ultra-thin graphitic carbon nitride nanosheets(PdTP/Pd_(SA)-CN)for high-efficiency photoreduction of CO_(2).The anchored Pd twinned nanoparticles donate electrons to adjacent single Pd–N_(4) sites through the carbon nitride networks,and the optimized PdTP/Pd_(SA)-CN photocatalyst exhibits a CO evolution rate up to 46.5μmol g^(-1) h^(-1) with nearly 100%selectivity.As revealed by spectroscopic and theoretical analyses,the superior photocatalytic activity is attributed to the lowered desorption barrier of carbonyl species at electron-enriched Pd single atoms,together with the improved efficiencies of light-harvesting and charge separation/transport.This work has demonstrated the engineering of the electron density of single active sites with twinned metal nanoparticles assisted by strong electronic interaction with the support of the atomic metal,and unveiled the underlying mechanism for expedited photocatalytic efficiency.展开更多
High piezoelectric composite films composed of poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)and ferromagnetic cobalt ferrite(CoFe_(2)O_(4))(0.00 wt%to 0.2 wt%)are prepared by a solution casting method acc...High piezoelectric composite films composed of poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)and ferromagnetic cobalt ferrite(CoFe_(2)O_(4))(0.00 wt%to 0.2 wt%)are prepared by a solution casting method accompanied by uniaxial stretching and high electric field poling.The decisive effect of the poling electric field on the power generating capability was confirmed by the experiments.For pure PVDF-HFP films,when the maximum electric field Emax is 120 MV/m,the calibrated open circuit voltage reaches 2.93 V,which is much higher than those poled at lower electric fields(70 MV/m:1.41 V;90 MV/m:2.11 V).Furthermore,the addition of CoFe_(2)O_(4)also influences the piezoelectricity dramatically.In the samples containing 0.15 wt%CoFe_(2)O_(4),the calibrated open circuit voltage increases to the maximum value of 3.57 V.Meanwhile,the relative fraction of theβ-phase and the crystallinity degree are 99%and 48%,respectively.The effects of CoFe_(2)O_(4)nanoparticles on initial crystallization,uniaxial stretching and high electric field poling are investigated by XRD,FTIR and DSC.展开更多
基金supported by Ministry of Higher Education,Malaysia,through the Fundamental Research Grant Scheme(FRGS)(Grant No.FRGS/1/2020/TK0/USM/02/27)。
文摘The immobilization of catalysts on supporting substrates for the removal of organic pollutants is a crucial strategy for mitigating catalyst loss during wastewater treatment.This study presented a rapid and cost-effective direct heating method for synthesizing MnO2 nanoflowers on coil substrates for the removal of organic pollutants.Traditional methods often require high power,expensive equipment,and long synthesis times.In contrast,the direct heating approach successfully synthesized MnO2 nanoflowers in just 10 min with a heating power of approximately 40 W·h after the heating power and duration were optimized.These nanoflowers effectively degraded 99%Rhodamine B in 60 min with consistent repeatability.The catalytic mechanisms are attributed to crystal defects in MnO2,which generate electrons to produce H2O2.Mn2+ions in the acidic solution further dissociate H2O2 molecules into hydroxyl radicals(·OH).The high efficiency of this synthesis method and the excellent reusability of MnO2 nanoflowers highlight their potential as a promising solution for the development of supporting MnO2 catalysts for organic dye removal applications.
基金supported by the Inner Mongolia Natural Science Foundation(2024QN02011)basic scientific research business expense project of colleges and universities directly under Inner Mongolia(2023QNJS131 and 2024QNJS127)Science and Technology Plan Program of Inner Mongolia Autonomous Region(2023YFDZ0031).
文摘Pure TiO_(2)and copper-modified titania(Cu/TiO_(2))nanoparticles were synthesized through sol gel combined with the pyrolysis method for the removal of Congo red(CR)in wastewater treatment.Surface morphology and structural evaluation utilized XRD,TEM,Raman,FTIR and BET techniques.Cu/TiO_(2)showed rich defects and a higher specific surface area than that of TiO_(2).The 1Cu/TiO_(2)(molar ratio Cu/TiO_(2)of 1/100)showed the best performance to adsorption of CR solution at different reaction conditions(contact duration,CR concentration,adsorbent dose,temperature,and initial pH).Adsorption kinetics and equilibrium isotherms were well-described with a pseudo-second-order kinetics and Freundlich model,respectively.The negative ΔG indicates stable adsorption of CR on the Cu/TiO_(2)surface.The adsorption efficiency only decreases by 6%after 5 cycles of adsorption regeneration.The successful synthesis of Cu/TiO_(2)offers a new possibility to address the problems related to CR dye from aqueous solutions.
文摘The p-block metal(In,Sn,Bi,etc.)-based electrocatalysts have exhibited excellent activity in the electrocatalytic CO_(2)reduction(ECR)to formate.However,the rapid decrease in catalytic activity caused by catalyst reconstruction and agglomeration under ECR conditions significantly restricts their practical applications.Herein,we developed a sulfur anchoring strategy to stabilize the high-density sub-3 nm In_(2)S_(3)nanoparticles on sulfur-doped porous carbon substrates(i-In_(2)S_(3)/S-C)for formate production.Systematic characterizations evidenced that the as-prepared catalyst exhibited a strong metal sulfide-support interaction(MSSI),which effectively regulated the electronic states of In_(2)S_(3),achieving a high formate Faradaic efficiency of 91%at−0.95 V vs.RHE.More importantly,the sulfur anchoring effectively immobilized the sub-3 nm In_(2)S_(3)nanoparticles to prevent them from agglomeration.It enabled the catalysts to exhibit much higher durability than the In_(2)S_(3)samples without sulfur anchoring,demonstrating that the strong MSSI and fast charge transfer on the catalytic interface could significantly promote the structural stability of In_(2)S_(3)catalysts.These results provide a viable approach for developing efficient and stable electrocatalysts for CO_(2)reduction.
基金support from the European Union Horizon 2020 program(project HERMES,nr.952184)the Ministry of Education,Youth and Sports of the Czech Republic for supporting CEMNAT(LM2023037)+1 种基金Czech-NanoLab(LM2023051)infrastructures for providing ALD,SEM,EDX,XPS,TEM,and XRDCzech Science Foundation(project 23-08019X,EXPRO).
文摘Synergistic interplays involving multiple active centers originating from TiO2 nanotube layers(TNT)and ruthenium(Ru)species comprising of both single atoms(SAs)and nanoparticles(NPs)augment the alkaline hydrogen evolution reaction(HER)by enhancing Volmer kinetics from rapid water dissociation and improving Tafel kinetics from efficient H*desorption.Atomic layer deposition of Ru with 50 process cycles results in a mixture of Ru SAs and 2.8-0.4 nm NPs present on TNT layers,and it emerges with the highest HER activity among all the electrodes synthesized.A detailed study of the Ti and Ru species using different high-resolution techniques confirmed the presence of Ti^(3+)states and the coexistence of Ru SAs and NPs.With insights from literature,the role of Ti^(3+),appropriate work functions of TNT layers and Ru,and the synergistic effect of Ru SAs and Ru NPs in improving the performance of alkaline HER were elaborated and justified.The aforementioned characteristics led to a remarkable performance by having 9mV onset potentials and 33 mV dec^(-1) of Tafel slopes and a higher turnover frequency of 1.72 H2 s^(-1) at 30 mV.Besides,a notable stability from 28 h staircase chronopotentiometric measurements for TNT@Ru surpasses TNT@Pt in comparison.
基金financially supported by the National Natural Science Foundation of China(Nos.U21A20308,22077088)Foundation from Science and Technology Major Project of Tibetan Autonomous Region of China(No.XZ202201ZD0001G)Foundation from Science and Technology Department of Sichuan Province(No.2021ZHCG0025)。
文摘Photoheranostics have emerged as a promising tool for cancer theranostics owing to their real-time feedback on treatment and their precise diagnosis.Among them,how to improve the photothermal conversion efficiency(PCE)of phototheranostic agents(PTAs)is the key factor for phototheranostic systems.Herein,we provided an efficient method to improve PCE and constructed a biocompatible nano-material ICR-Qu@NH_(2)-Fe_(3)O_(4)@PEG(QNFP)by combing near-infrared second region(NIR-Ⅱ)molecular dye ICR-Qu and amino-modified magnetic nanoparticles and then encapsulated by DSPE-m PEG2000.QNFP exhibited excellent performance for photothermal therapy with a high PCE of 95.6%.Both in vitro and in vivo experiments indicated that QNFP could inhibit the growth of tumors under laser irradiation with low toxicity and realized real-time NIR-Ⅱfiuorescent imaging of tumors.In general,we realized a simple but efficient method to improve the PCE of NIR-Ⅱmolecular dye without reduce its quantum yield,which is an ideal choice for cancer diagnosis and treatment.
基金financially supported by the National Natural Science Foundation of China(Nos.51878092,51608067)the Scientific and Technological Innovation Special Program of Social Livelihood of Chongqing(No.cstc2015shmsztzx0053)the Fundamental Research Funds for the Central Universities(No.2019CDXYCH0026)
文摘Changes in solution chemistry and transport conditions can lead to the release of deposited MnO2 nanoparticles from a solid interface,allowing them to re-enter the aqueous environment.Understanding the release behavior of Mn02 nanoparticles from naturally occurring surfaces is critical for better prediction of the transport potential and environmental fate of Mn02 nanoparticles.In this study,the release of Mn02 nanoparticles was investigated using a quartz crystal microbalance with dissipation monitoring(QCM-D),and different environmental surface types,solution pH values and representative macromolecular organics were considered.Mn02 nanoparticles were first deposited on crystal sensors at elevated NaN03 concentrations before being rinsed with double-deionized water to induce their remobilization.The results reveal that the release rate of Mn02 depends on the surface type,in the decreasing order:SiO2>Fe304>Al2 O3,resulting from electrostatic interactions between the surface and particles.Moreover,differences in solution pH can lead to variance in the release behavior of Mn02 nanoparticles.The release rate from surfaces was significantly higher at pH 9.8 that at 4.5,indicating that alkaline conditions were more favorable for the mobilization of Mn02 in the aquatic environment.In the presence of macromolecular organics,bovine serum albumin(BSA)can inhibit the release of Mn02 from the surfaces due to attractive forces.In presence of humic acid(HA)and sodium alginate(SA),the Mn02 nanoparticles were more likely to be mobile,which may be associated with a large repulsive barrier imparted by steric effects.
基金Project supported by the National Natural Science Foundation of China(U20A20274,52071158,51701085,U1664254)the Six Talents Peak Project of Jiangsu Province(2018-XCL-202)+1 种基金the Open Funds of SKLMMC of SJTU(MMC-KF18-16)the Jiangsu Province Key Laboratory of High-end Structural Materials(HSM1803,1902)。
文摘In this study, the in-situ synthesized ZrB_(2) nanoparticles and rare earth Sc were introduced to enhance the strength and ductility of 7N01 aluminum alloy, via the generation of high-melting and uniform nanodispersoids. The microstructure and mechanical property evolution of the prepared composites and the interaction between ZrB_(2) and Sc were studied in detail. The microstructure investigation shows that the introduction of rare earth scandium(Sc) can promote the distribution of ZrB_(2) nanoparticles, by improving their wettability to the Al melt. Meanwhile, the addition of rare earth Sc also modifies the coarse Al Zn Mg Mn Fe precipitated phases, refines the matrix grains and generates high-melting Al_3(Sc,Zr)/Al_3Sc nanodispersoids. Tensile tests of the composites show that with the combinatorial introduction of ZrB_(2) and Sc, the strength and ductility of the composites are improved simultaneously compared with the corresponding 7N01 alloy, ZrB_(2) /7N01 composite and Sc/7N01 alloy. And the optimum contents of ZrB_(2) and Sc are 3 wt% and 0.2 wt% in this study. The yield strength, ultimate strength and elongation of(3 wt% ZrB_(2) +0.2 wt% Sc)/7N01 composite are 477 MPa, 506 MPa and 9.8%, increased about 18.1%, 12.2%and 38% compared to 7N01 alloy. Furthermore, the cooperation strengthening mechanisms of ZrB_(2) and Sc are also discussed.
基金supported by the Na⁃tional Natural Science Foundation of China(Nos.12462006,12062016)the high-performance computing services of⁃fered by the Information Center of Nanchang Hangkong Uni⁃versity.
文摘Molecular dynamics(MD)simulations are employed to delve into the multifaceted effects of TiB_(2) nanoparticles on the intricate grain refinement mechanism,microstructural evolution,and tensile performance of Inconel 718 superalloys during the rapid directional solidification.Specifically,the study focuses on elucidating the role of TiB2 nanoparticles in augmenting the nucleation rate during the rapid directional solidification process of Ni_(60)Cr_(21)Fe_(19) alloy system.Furthermore,subsequent tensile simulations are conducted to comprehensively evaluate the anisotropic behavior of tensile properties within the solidified microstructures.The MD results reveal that the incorporation of TiB₂nanoparticles during the rapid directional solidification of the Ni_(60)Cr_(21)Fe_(19) significantly enhances the average nucleation rate,escalating it from 1.27×10^(34)m^(-3)·s^(-1)to 2.55×10^(34)m^(-3)·s^(-1).Notably,within the face centered cube(FCC)structure,Ni atoms exhibit pronounced compositional segregation,and the solidified alloy maintains an exceptionally high dislocation density reaching up to 10^(16)m^(-2).Crucially,the rapid directional solidification process imparts a distinct microstructural anisotropy,leading to a notable disparity in tensile strength.Specifically,the tensile strength along the solidification direction is markedly superior to that perpendicular to it.This disparity arises from different deformation mechanisms under varying loading orientations.Tensile stress perpendicular to the solidification direction encourages the formation of smooth and organized mechanical twins.These twins act as slip planes,enhancing dislocation mobility and thereby improving stress relaxation and dispersion.Moreover,the results underscore the profound strengthening effect of TiB_(2) nanoparticles,particularly in enhancing the tensile strength along the rapid directional solidification direction.
文摘Foam stability tests were performed using sodium dodecyl sulfate(SDS)surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations,and the half-life of CO_(2) foam was measured.The mechanism of foam stability reduction in the presence of asphaltene was analyzed by scanning electron microscope(SEM),UV adsorption spectrophotometric concentration measurement and Zeta potential measurement.When the mass ratio of synthetic oil to foam-formation suspension was 1:9 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 751 s to 239 s,and the half-life of SDS/silica-stabilized foams decreased from 912 s to 298 s.When the mass ratio of synthetic oil to foam-formation suspension was 2:8 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 526 s to 171 s,and the half-life of SDS/silica-stabilized foams decreased from 660 s to 205 s.In addition,due to asphaltene-SDS/silica interaction in the aqueous phase,the absolute value of Zeta potential decreases,and the surface charges of particles reduce,leading to the reduction of repulsive forces between two interfaces of thin liquid film,which in turn,damages the foam stability.
基金supported by Natural Science Foundation of Henan Province of China(162300410253)the Open Research Fund of State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization,China Pingmei Shen-ma Group(41040220181107-8).
文摘Porous silica nano-flowers(KCC-1)immobilized Pt-Pd alloy NPs(Pt-Pd/KCC-1)with different mass ratios of Pd and Pt were successfully prepared by a facile in situ one-step reduction,using hydrazinium hydroxide as a reducing agent.The as-synthesized silica nanospheres possess radial fibers with a distance of 15 nm,exhibiting a high specific surface area(443.56 m^(2)·g^(-1)).Meanwhile,the obtained Pt-Pd alloy NPs are uniformly dispersed on the silica surface with a metallic particle size of 4-6 nm,which exist as metallic Pd and Pt on the surface of monodisperse KCC-1,showing the transfer of electrons from Pd to Pt.The as-synthesized 2.5%Pt-2.5%Pd/KCC-1 exhibited excellent catalytic activity and stability for the continuous dehydrogenation of 2-methoxycyclohexanol to prepare guaiacol.Compared with Pt or Pd single metal supported catalysts,the obtained 2.5%Pt-2.5%Pd/KCC-1 shows 97.2%conversion rate of 2-methoxycyclohexanol and 76.8%selectivity for guaiacol,which attributed to the significant synergistic effect of bimetallic Pt-Pd alloy NPs.Furthermore,turn over frequency value of the obtained 2.5%Pt-2.5%Pd/KCC-1 NPs achieved 4.36 s^(-1),showing higher catalytic efficiency than other two monometallic catalysts.Reaction pathways of dehydro-aromatization of 2-methoxycyclohexanol over the obtained catalyst are proposed.Consequently,the obtained 2.5%Pt-2.5%Pd/KCC-1 NPs prove their potential in the dehydrogenation of 2-methoxycyclohexanol,while the kinetics and mechanistic study of the dehydrogenation reaction over the catalyst in a continuous fixed-bed reactor may provide valuable information for the development of green,outstanding and powerful synthetic pathway of guaiacol.
文摘The influence of Mo and ZrO_(2)nanoparticles addition on the interfacial properties and shear strength of Sn58Bi solder joint was investigated.The interfacial microstructures of Sn58Bi/Cu,Sn58Bi+Mo/Cu and Sn58Bi+ZrO_(2)/Cu solder joints were analysed using a scanning electron microscope(SEM)coupled with energy dispersive X-ray(EDX)and the X-ray diffraction(XRD).Intermetallic compounds(IMCs)of MoSn_(2)are detected in the Sn58Bi+Mo/Cu solder joint,while SnZr,Zr_(5)Sn_(3),ZrCu and ZrSn_(2)are detected in Sn58Bi+ZrO_(2)/Cu solder joint.IMC layers for both composite solders comprise of Cu_(6)Sn_(5) and Cu_(3)Sn.The SEM images of these layers were used to measure the IMC layer’s thickness.The average IMC layer’s thickness is 1.4431μm for Sn58Bi+Mo/Cu and 0.9112μm for Sn58Bi+ZrO_(2)/Cu solder joints.Shear strength of the solder joints was investigated via the single shear lap test method.The average maximum load and shear stress of the Sn58Bi+Mo/Cu and Sn58Bi+ZrO_(2)/Cu solder joints are increased by 33%and 69%,respectively,as compared to those of the Sn58Bi/Cu solder joint.By comparing both composite solder joints,the latter prevails better as adding smaller sized ZrO_(2)nanoparticles improves the interfacial properties granting a stronger solder joint.
基金supported by the National Natural Science Foundation of China(Nos.22371272 and 22301295)the Fundamental Research Funds for the Central Universities(Nos.YD2060002036 and WK5290000004)+1 种基金International Partnership Program of the Chinese Academy of Sciences(No.123GJHZ2022064MI)the Collaborative Innovation Program of Hefei Science Center,CAS(No.2022HSC-CIP014)。
文摘Single-chain nanoparticles represent an emerging class of nanomaterials designed to mimic protein's folding paradigm.Intrachain covalent crosslinking toward the formation of single-chain nanoparticles encounters complex energy landscapes,leading to the potential occurrence of misfolding issues.While noncovalent crosslinking can circumvent this issue,the resulting single-chain nanoparticles exhibit lower structural stability compared to their covalently crosslinked counterparts.In this study,we present a novel approach for the synthesis of single-chain nanoparticles,achieved through the combination of non-covalent and covalent intramolecular crosslinking.Cyanostilbenes grafted onto the linear polymer form intrachain non-covalent stacks aided by hydrogen bonds,leading to the formation of non-covalently crosslinked single-chain nanoparticles.These nanoparticles undergo conversion to covalently crosslinked nanostructures through subsequent photo-irradiation using[2+2]photocycloaddition,a process facilitated by the supramolecular confinement effect.Consequently,the resulting single-chain nanoparticles demonstrate both intrachain folding efficiency and substantial stability,offering significant potential for advancing applications across diverse fields.
文摘Cerium-doped zirconium-based NH_(2)-UiO-66 nanoparticles were synthesized in ionic liquid 1-butyl-3-methylimidazolium acetate at room temperature.The crystal structure and morphology were studied using X-ray diffraction,infrared spectroscopy,scanning electron microscopy and transmission electron microscopy.The valence state and distribution of elements in the obtained materials were examined using X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy.Catalytic performance studies show that the cerium-doped NH_(2)-UiO-66 exhibits improved catalytic efficiency in the cycloaddition reaction of 1,2-butylene oxide and carbon dioxide than pure NH_(2)-UiO-66.Studies on the photoelectric properties indicate that the cerium-doped NH_(2)-UiO-66 catalyst possesses strong photocurrent response,low interfacial charge transfer resistance,narrow band gap,and low flat band potential.This work provides a new approach of synthesizing high-performance catalyst for photocatalytic CO_(2) cycloaddition.
基金the National Natural Science Foundation of China(Nos.21971132 and 52072197)Outstanding Youth Foundation of Shandong Province,China(No.ZR2019JQ14)+7 种基金Youth Innovation and Technology Foundation of Shandong Higher Education Institutions,China(No.2019KJC004)Major Scientific and Technological Innovation Project(No.2019JZZY020405)Major Basic Research Program of Natural Science Foundation of Shandong Province(No.ZR2020ZD09)Taishan Scholar Young Talent Program(No.tsqn201909114)the Key Laboratory of Resource Chemistry,Ministry of Education(No.KLRC_ME2101)Scientific and Technological Innovation Promotion Project for Small-medium Enterprises of Shandong Province(No.2022TSGC1257)Major Research Program of Jining City(No.2020ZDZP024)The 111 Project of China(No.D20017).
文摘Lithium (Li)-CO_(2) battery is rising as an attractive energy-storage system with the competence of CO_(2) conversion/fixation. However, its practical development is seriously hindered by the high overpotential. Herein, a rational design on a highly catalytic Li-CO_(2) battery electrode built by graphdiyne powder as a multi-functional laminar scaffold with anchored highly dispersed Ru nanoparticles is explored. The strong interaction between the abundant acetylenic bond sites of graphdiyne scaffold and Ru nanoparticles can effectively promote the electrochemical progress and reduce the voltage polarization. The unique channels architecture of the cathodic catalyst with enough space not only accelerates CO_(2) diffusion and electrons/Li+ transport, but also allows a large amount of accommodation for discharged product (Li2CO3) to assure an advanced capacity. The corresponding Li-CO_(2) battery displays an advanced discharged capacity of 15,030 mAh/g at 500 mA/g, great capacity retention of 8873 mAh/g at 2 A/g, high coulombic efficiency of 97.6% at 500 mA/g and superior life span for 120 cycles with voltage gap of 1.67 V under a restricted capacity of 1000 mAh/g at 500 mA/g. Ex/in-situ studies prove that synergy between Ru nanoparticles and acetylene bonds of GDY can boost the round-trip CO_(2)RR and CO_(2)ER kinetics.
基金supported by the National Natural Science Foundation of China(22101182)the Shenzhen Science and Technology Program(Nos.JCYJ20210324095202006,JCYJ20220531095813031,and JCYJ20230807140700001)Guangdong Basic and Applied Basic Research Foundation(2022A1515010318).
文摘Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the electrode.Building upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral electrolyte.Employing CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow cell.Furthermore,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)products.This advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences,China(Nos.XDA23010300 and XDA23010000)National Science Foundation of China,China(Nos.52200137 and 21725102)+1 种基金the Plan for“National Youth Talents”GuangDong Basic and Applied Basic Research Foundation(No.2021A1515110427)。
文摘Developing low-loading single-atom catalysts with superior catalytic activity and selectivity in formaldehyde(HCHO)oxidation at room temperature remains challenging.Herein,ZrO_(2)nanoparticles coupled low-loading Ir single atoms in N-doped carbon(Ir_(1)-N-C/ZrO_(2))was prepared.The optimal Ir_(1)-N-C/ZrO_(2)with 0.25 wt%Ir loading delivers the high HCHO removal and conversion efficiency(>95%)at 20℃,which is higher than that over Ir_(1)-N-C with the same Ir loading.The specific rate can reach 1285.6 mmol gIr^(-1)h^(-1),surpassing the Ir based catalysts reported to date.Density functional theory calculation results and electron spin resonance spectra indicate that the introduction of Zr O_(2)nanoparticles modulate the electronic structure of the Ir single atoms,promoting O_(2)activation to·O_(2)^(–).Moreover,the Ir-C-Zr channel is favorable for the dissociation of·O_(2)^(–)to active oxygen atom(*O),and further accelerates the transformation of HCHO and intermediates(dioxymethylene and formates)to CO_(2)and H_(2)O.This work provides a facile strategy to design low-loading single-atom catalysts with high catalytic activity toward HCHO oxidation.
基金supported by the National Natural Science Foundation of China(22005043,52272193)the National Key Research and Development Program of China(2019YFA0709102 and 2020YFA0714502)+1 种基金the Liaoning Revitalization Talents Program(XLYC2007038,XLYC2008032)the Fundamental Research Funds for the Central Universities(DUT22LAB602,DUT22GJ201).
文摘Advanced photovoltaics,such as ultra-flexible perovskite solar cells(UF-PSCs),which are known for their lightweight design and high power-to-mass ratio,have been a long-standing goal that we,as humans,have continuously pursued.Unlike normal PSCs fabricated on rigid substrates,producing high-efficiency UF-PSCs remains a challenge due to the difficulty in achieving full coverage and minimizing defects of metal halide perovskite(MHP)films.In this study,we utilized Al_(2)O_(3) nanoparticles(NPs)as an inorganic surface modifier to enhance the wettability and reduce the roughness of poly-bis(4-phenyl)(2,4,6-trimethylphenyl)amine simultaneously.This approach proves essentials in fabricating UF-PSCs,enabling the deposition of uniform and dense MHP films with full coverage and fewer defects.We systematically investigated the effect of Al_(2)O_(3) NPs on film formation,combining simulation with experiments.Our strategy not only significantly increases the power conversion efficiency(PCE)from 11.96%to 16.33%,but also promotes reproducibility by effectively addressing the short circuit issue commonly encountered in UF-PSCs.Additionally,our UF-PSCs demonstrates good mechanical stability,maintaining 98.6%and 79.0%of their initial PCEs after 10,000 bending cycles with radii of 1.0 and 0.5 mm,respectively.
基金supported by the National Natural Science Foundation of China(No.22278203,No.22279057)the support of the Inner Mongolia major science and technology project(2021ZD0042),Development of integrated technology for CO_(2)emission reduction in electric power metallurgy industry
文摘Solid oxide electrolysis cells(SOECs),displaying high current density and energy efficiency,have been proven to be an effective technique to electrochemically reduce CO_(2)into CO.However,the insufficiency of cathode activity and stability is a tricky problem to be addressed for SOECs.Hence,it is urgent to develop suitable cathode materials with excellent catalytic activity and stability for further practical application of SOECs.Herein,a reduced perovskite oxide,Pr_(0.35)Sr_(0.6)Fe_(0.7)Cu_(0.2)Mo_(0.1)O_(3-δ)(PSFCM0.35),is developed as SOECs cathode to electrolyze CO_(2).After reduction in 10%H_(2)/Ar,Cu and Fe nanoparticles are exsolved from the PSFCM0.35 lattice,resulting in a phase transformation from cubic perovskite to Ruddlesden-Popper(RP)perovskite with more oxygen vacancies.The exsolved metal nanoparticles are tightly attached to the perovskite substrate and afford more active sites to accelerate CO_(2)adsorption and dissociation on the cathode surface.The significantly strengthened CO_(2)adsorption capacity obtained after reduction is demonstrated by in situ Fourier transform-infrared(FT-IR)spectra.Symmetric cells with the reduced PSFCM0.35(R-PSFCM0.35)electrode exhibit a low polarization resistance of 0.43Ωcm^(2)at 850℃.Single electrolysis cells with the R-PSFCM0.35 cathode display an outstanding current density of 2947 mA cm^(-2)at 850℃and 1.6 V.In addition,the catalytic stability of the R-PSFCM0.35 cathode is also proved by operating at 800℃with an applied constant current density of 600 mA cm^(-2)for 100 h.
基金We appreciate the financial support from the National Natural Science Foundation of China(22272150,22102145)the Major Program of Zhejiang Provincial Natural Science Foundation(LD22B030002)+3 种基金Zhejiang Provincial Ten Thousand Talent Program(2021R51009)Zhejiang Provincial Natural Science Foundation of China(LQ23B030006,LY22B030012)Shandong Provincial Natural Science Foundation of China(2020MB053)the Fundamental Research Funds for the Central Universities(DUT22RC(3)084).
文摘Modulating electronic structures of single-atom metal cocatalysts is vital for highly active photoreduction of CO_(2),and it's especially challenging to develop a facile method to modify the dispersion of atomical photocatalytic sites.We herein report an ion-loading pyrolysis route to in-situ anchor Pd single atoms as well as twinned Pd nanoparticles on ultra-thin graphitic carbon nitride nanosheets(PdTP/Pd_(SA)-CN)for high-efficiency photoreduction of CO_(2).The anchored Pd twinned nanoparticles donate electrons to adjacent single Pd–N_(4) sites through the carbon nitride networks,and the optimized PdTP/Pd_(SA)-CN photocatalyst exhibits a CO evolution rate up to 46.5μmol g^(-1) h^(-1) with nearly 100%selectivity.As revealed by spectroscopic and theoretical analyses,the superior photocatalytic activity is attributed to the lowered desorption barrier of carbonyl species at electron-enriched Pd single atoms,together with the improved efficiencies of light-harvesting and charge separation/transport.This work has demonstrated the engineering of the electron density of single active sites with twinned metal nanoparticles assisted by strong electronic interaction with the support of the atomic metal,and unveiled the underlying mechanism for expedited photocatalytic efficiency.
基金supported by National Natural Science Foundation of China(No.51703015)Fundamental Research Funds for the Central Universities(No.2020CDJQY-A008).
文摘High piezoelectric composite films composed of poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)and ferromagnetic cobalt ferrite(CoFe_(2)O_(4))(0.00 wt%to 0.2 wt%)are prepared by a solution casting method accompanied by uniaxial stretching and high electric field poling.The decisive effect of the poling electric field on the power generating capability was confirmed by the experiments.For pure PVDF-HFP films,when the maximum electric field Emax is 120 MV/m,the calibrated open circuit voltage reaches 2.93 V,which is much higher than those poled at lower electric fields(70 MV/m:1.41 V;90 MV/m:2.11 V).Furthermore,the addition of CoFe_(2)O_(4)also influences the piezoelectricity dramatically.In the samples containing 0.15 wt%CoFe_(2)O_(4),the calibrated open circuit voltage increases to the maximum value of 3.57 V.Meanwhile,the relative fraction of theβ-phase and the crystallinity degree are 99%and 48%,respectively.The effects of CoFe_(2)O_(4)nanoparticles on initial crystallization,uniaxial stretching and high electric field poling are investigated by XRD,FTIR and DSC.
