Constructing high-performance electrocatalysts for oxygen evolution reaction(OER) using a simple and economical strategy is considerably meaningful yet still challenging. Herein, Co(OH)_(2)/Mo_(2)Ti C_(2)T_(x)(where T...Constructing high-performance electrocatalysts for oxygen evolution reaction(OER) using a simple and economical strategy is considerably meaningful yet still challenging. Herein, Co(OH)_(2)/Mo_(2)Ti C_(2)T_(x)(where Txrepresents the surface functional groups,-O,-OH and-F) hetero-nanosheets were facilely prepared by the in situ topochemical transformation at room temperature towards efficient OER. The integrity of Co(OH)_(2)nanosheets and Mo_(2)Ti C_(2)T_(x) nanosheets affords interfacial coupling to optimize the electronic structures of Co and Mo ions, which endows the high electron transfer efficiency and rapid reaction kinetics. As a result, the Co(OH)_(2)/Mo_(2)Ti C_(2)T_(x) hetero-nanosheets exhibit excellent OER performances with low overpotentials of 283 m V on glass-carbon electrode, and 227 m V on nickel foam at 10 m A/cm^(2). Furthermore, the decent anti-alkali ability underpins superior operational stability exceeding 100 h, demonstrating grand potential in practical applications. This work provides a new insight for the synthesis of efficient and cost-effective two-dimensional(2D) material-based electrocatalysts.展开更多
Optimizing the interfacial environments of electrodes has emerged as an effective strategy to improve their electrochemical properties.Amorphous/crystalline interfacial coupling can effectively utilize the advantages ...Optimizing the interfacial environments of electrodes has emerged as an effective strategy to improve their electrochemical properties.Amorphous/crystalline interfacial coupling can effectively utilize the advantages of amorphous materials to optimize the interfacial structure for efficient Na^(+)storage.Herein,the dense homologous amorphous/crystalline heterointerfaces are in situ achieved in N-doped carbon nanobundles via self-polymerization and precise nitriding(Mo–N/Mo_(2)N@C).The amorphous Mo–N rich in unsaturated vacancy defects provides abundant active sites with isotropic ion-transport channels,and can effectively alleviate structural stress from crystalline Mo_(2)N.Meanwhile,the conductive Mo_(2)N can facilitate effective electron transfer,augmented further by the carbon encapsulation.Theoretical calculations reveal that the dense heterointerfaces can optimize the electronic structure and shift the d-p orbital centers of Mo and N upward,thereby enhancing the adsorption and mobility of Na^(+),and ultimately improving the charge transport and storage efficiency of the electrode.The Mo–N/Mo_(2)N@C as an anode delivers a 46.9%increase in reversible capacity over Mo_(2)N@C,reaching 461.1 m Ah.g^(–1)at 0.1 A.g^(–1),along with improved rate capability and cycling stability,underlining its practical utility.These results suggest that the homologous interfacial coupling can boost the storage properties of nitrides,providing a valuable reference for improving the properties of electrodes with low theoretical capacities.展开更多
Rechargeable magnesium batteries(RMBs)have garnered significant attention in energy storage applications due to their high capacity,low cost,and high safety.However,the strong polarization effect and slow kinetic de-i...Rechargeable magnesium batteries(RMBs)have garnered significant attention in energy storage applications due to their high capacity,low cost,and high safety.However,the strong polarization effect and slow kinetic de-intercalation of Mg^(2+)in the cathode limit their commercial application.This study presents a novel interface-coupled V_(2)CT_(x)@VS_(4)heterostructure through a one-step hydrothermal process.In this architecture,V_(2)CT_(x)and VS_(4)can mutually support their structural framework,which effectively prevents the structural collapse of V_(2)CT_(x)MXene and the aggregation of VS_(4).Crucially,interfacial coupling between V_(2)CT_(x)and VS_(4)induces strong V-S bonds,substantially enhancing structural stability.Benefiting from these advantages,the heterostructure exhibits high specific capacity(226 mAh g^(-1)at 100 mA g^(-1))and excellent long-cycle stability(89% capacity retention after 1000 cycles at 500 mA g^(-1)).Furthermore,the Mg^(2+)storage mechanism in the V_(2)CT_(x)@VS_(4)composite was elucidated through a series of ex-situ characterizations.This work provides a feasible strategy for designing V_(2)CT_(x)MXene-based cathodes with high capacity and extended cyclability for RMBs.展开更多
A series of In_(x)Sb_(2-x)S_(3) nanosheets modified g-C_(3)N_(4)(In_(x)Sb_(2-x)S_(3)-TCN)heterojunctions with different g-C_(3)N_(4) contents were fabricated by an in situ deposition method.All the In_(x)Sb_(2-x)S_(3)...A series of In_(x)Sb_(2-x)S_(3) nanosheets modified g-C_(3)N_(4)(In_(x)Sb_(2-x)S_(3)-TCN)heterojunctions with different g-C_(3)N_(4) contents were fabricated by an in situ deposition method.All the In_(x)Sb_(2-x)S_(3)-TCN composites were applied as photocatalysts in Cr(Ⅵ)polluted water treatment and the results displayed that In_(x)Sb_(2-x)S_(3)-TCN could effectively remove Cr(Ⅵ)under visible light through synergistic effects of adsorption and photocatalytic reduction.Especially,In_(x)Sb_(2-x)S_(3)-TCN-70(70 mg g-C_(3)N_(4)) exhibited the most excellent adsorption and photocatalytic reduction performance among all composites,which possessed a high equilibrium adsorption capacity of 12.45 mg/g in a 30.0 mg/L Cr(Ⅵ)aqueous solution,and reduced Cr(Ⅵ)to Cr(Ⅲ)within 10 min under visible light irradiation.DRS and PL results indicated that the interfacial coupling effect between g-C_(3)N_(4)and In_(x)Sb_(2-x)S_(3) enhanced the utilization efficiency of visible light and suppressed photoinduced carrier recombination,which improved the photocatalytic activity of composites.Moreover,the photocatalyst exhibited satisfactory reduction activity and good stability after 5 cycles of Cr(Ⅵ)adsorptionphotoreduction.展开更多
Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mec...Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mechanism and the interfacial coupling in Bi_(0.5)Na_(0.5)TiO_(3)/SrTiO_(3)(BNT/STO)heterointerfaces are investigated by the aberration-corrected scanning transmission electron microscopy,which is synthesized by a hydrothermal method.The results illustrate that 4 mol/L NaOH leads to not only the epitaxial growth of the BNT film but also the mutual diffusion of elements.The uneven distribution of local elements in BNT films is observed and confirmed to impact the cation displacements of B-site and lattice distortion.However,the overall trend of B-site cation displacement at the BNT/STO heterointerfaces is dominated by the interfacial strain.Additionally,the oxygen octahedral tilt exhibits continuous tilt patterns of a^(0)a^(0)a^(0)-a−b^(0)c−-a^(0)a^(0)c−-a^(0)b−c−-a−b−c−from the substrate to BNT film due to the constraint of the substrate and presents a strong correlation with cation displacement.These results are helpful to understand the underlying atomic structures and physical properties of BNT epitaxial thin films.展开更多
Developing efficient electrocatalysts for hydrogen evolution reaction(HER) is of great importance in contemporary water electrolysis technology. Here, a novel hierarchically sea urchin-like electrocatalyst(Mo_(4)O_(11...Developing efficient electrocatalysts for hydrogen evolution reaction(HER) is of great importance in contemporary water electrolysis technology. Here, a novel hierarchically sea urchin-like electrocatalyst(Mo_(4)O_(11)-MoS_(2)-VO_(2)) is synthesized by hydrothermal deposition and post-annealing strategy. The optimized electrocatalyst behaves as a high active hydrogen evolution electrode in 0.5 mol/L H_(2)SO_(4). This electrode needs overpotential of only 43 m V to achieve 10 m A/cm^(2)with a Tafel slope of 37 m V/dec and maintains its catalytic activity for at least 36 h. Better than most previously reported non-noble metal electrocatalysts anchored on carbon cloth. It is worth mentioning that the hierarchical sea urchin-like structure promotes the redistribution of electrons and provides more catalytic active sites. This strategy shows a way for the construction of inexpensive non-noble metal electrocatalysts in the future.展开更多
The effect of interfacial coupling on rectification in an organic co-oligomer spin diode is investigated theoretically by considering spin-independent and spin-resolved couplings respectively. In the case of spin-inde...The effect of interfacial coupling on rectification in an organic co-oligomer spin diode is investigated theoretically by considering spin-independent and spin-resolved couplings respectively. In the case of spin-independent coupling, an optimal interfacial coupling strength with a significant enhanced rectification ratio is found, whose value depends on the structural asymmetry of the molecule. In the case of spin-resolved coupling, we found that only the variation of the interfacial coupling with specific spin is effective to modulate the rectification, which is due to the spin-filtering property of the central asymmetric magnetic molecule. A transition of the spin-current rectification between parallel spin-current rectification and antiparallel spin-current rectification may be observed with the variation of the spin-resolved interfacial coupling. The interfacial effect on rectification is further analyzed from the spin-dependent transmission spectrum at different biases.展开更多
The magnetic anisotropy manipulation in the Sm_(3)Fe_(5)O_(12)(SmIG)films and its effect on the interfacial spin coupling in the CoFe/SmIG heterostructures were studied carefully.By switching the orientation of the Gd...The magnetic anisotropy manipulation in the Sm_(3)Fe_(5)O_(12)(SmIG)films and its effect on the interfacial spin coupling in the CoFe/SmIG heterostructures were studied carefully.By switching the orientation of the Gd_(3)Ga_(5)O_(12)substrates from(111)to(001),the magnetic anisotropy of obtained SmIG films shifts from in-plane to out-of-plane.Similar results can also be obtained in the films on Gd_(3)Ga_(5)O_(12)substrates,which identifies the universality of such orientation-induced magnetic anisotropy switching.Additionally,the interfacial spin coupling and magnetic anisotropy switching effect on the spin wave in CoFe/SmIG magnetic heterojunctions have also been explored by utilizing the time-resolved magneto-optical Kerr effect technique.It is intriguing to find that both the frequency and effective damping factor of spin precession in CoFe/SmIG heterojunctions can be manipulated by the magnetic anisotropy switching of SmIG films.These findings not only provide a route for the perpendicular magnetic anisotropy acquisition but also give a further path for spin manipulation in magnetic films and heterojunctions.展开更多
Carrier transport in colloidal quantum dot(CQD)films is strongly influenced by the interfacial coupling between CQDs.Currently,the shape of PbS CQDs synthesized using traditional methods results in random orientation ...Carrier transport in colloidal quantum dot(CQD)films is strongly influenced by the interfacial coupling between CQDs.Currently,the shape of PbS CQDs synthesized using traditional methods results in random orientation relationships between the crystal facets in CQD films,limiting the coupling strength and the final performance of optoelectronic devices.In this study,post-synthesis surface treatment of PbS CQDs was employed to achieve facet control during secondary growth,manipulating the facets of PbS CQDs at the nanoscale to enhance interfacial coupling within CQD films.Additionally,mixed ligands of PbX_(2)(X=Br,I)and anhydrous sodium acetate were used to passivate the PbS CQDs,ensuring sufficient passivation.This method combines facet passivation with strong coupling through the(100)facets of CQDs,thereby enhancing carrier mobility and improving device performance.Experimental results showed that,compared to standard PbS CQD films,the electron and hole mobilities of the PbS CQD films subjected to secondary growth were significantly improved,with hole mobility increased by 6 times.Photodetectors fabricated using these films achieved a quantum efficiency of 33%at 1500 nm under 0 V bias,a threefold improvement compared to standard devices.展开更多
Recent advances in van der Waals(vdW) ferroelectrics have sparked the development of related heterostructures with non-volatile and field-tunable functionalities. In vdW ferroelectric heterojunctions, the interfacial ...Recent advances in van der Waals(vdW) ferroelectrics have sparked the development of related heterostructures with non-volatile and field-tunable functionalities. In vdW ferroelectric heterojunctions, the interfacial electrical characteristics play a crucial role in determining their performance and functionality. In this study,we explore the interfacial polarization coupling in two-dimensional(2D) ferroelectric heterojunctions by fabricating a graphene/h-BN/CuInP_(2)S_(6)/α-In_(2)Se_(3)/Au ferroelectric field-effect transistor. By varying the gate electric field, the CuInP_(2)S_(6)/α-In_(2)Se_(3) heterojunction displays distinct interfacial polarization coupling states, resulting in significantly different electrical transport behaviors. Under strong gate electric fields, the migration of Cu ions further enhances the interfacial polarization effect, enabling continuous tuning of both the polarization state and carrier concentration in α-In_(2)Se_(3). Our findings offer valuable insights for the development of novel multifunctional devices based on 2D ferroelectric materials.展开更多
Tuning and optimization of electronic structures and related reaction energetics are critical toward the rational design of efficient electrocatalysts.Herein,experimental and theoretical calculation demonstrate the or...Tuning and optimization of electronic structures and related reaction energetics are critical toward the rational design of efficient electrocatalysts.Herein,experimental and theoretical calculation demonstrate the originally inert N site within polyaniline(PANI)can be activated for hydrogen evolution by proper d-πinterfacial electronic coupling with metal oxide.As a result,the assynthesized WO3 assemblies@PANI via a facile redox-induced assembly and in situ polymerization,exhibits the electrocatalytic production of hydrogen better than other control samples including W18O49@PANI and most of the reported nobel-metal-free electrocatalysts,with low overpotential of 74 mV at 10 mA·cm−2 and small Tafel slope of 46 mV·dec−1 in 0.5M H2SO4(comparable to commercial Pt/C).The general efficacy of this methodology is also validated by extension to other metal oxides such as MoO3 with similar improvements.展开更多
Cost-effective and stable electrocatalysts with ultra-high current densities for electrochemical oxygen evolution reaction(OER)are critical to the energy crisis and environmental pollution.Herein,we report a superaero...Cost-effective and stable electrocatalysts with ultra-high current densities for electrochemical oxygen evolution reaction(OER)are critical to the energy crisis and environmental pollution.Herein,we report a superaerophobic three dimensional(3D)heterostructured nanowrinkles of bimetallic selenides consisting of crystalline NiSe2 and NiFe2Se4 grown on NiFe alloy(NiSe2/NiFe2Se4@NiFe)prepared by a thermal selenization procedure.In this unique 3D heterostructure,numerous nanowrinkles of NiSe2/NiFe2Se4 hybrid with a thickness of ~100 nm are grown on NiFe alloy in a uniform manner.Profiting by the large active surface area and high electronic conductivity,the superaerophobic NiSe2/NiFe2Se4@NiFe heterostructure exhibits excellent electrocatalytic activity and durability towards OER in alkaline media,outputting the low potentials of 1.53 and 1.54 V to achieve ultra-high current densities of 500 and 1000 mA cm^−2,respectively,which is among the most active Ni/Fe-based selenides,and even superior to the benchmark Ir/C catalyst.The in-situ derived FeOOH and NiOOH species from NiSe2/NiFe2Se4@NiFe are deemed to be efficient active sites for OER.展开更多
Solar-powered photocatalytic hydrogen production from water using semiconductors provides an eco-friendly and promising approach for converting solar energy into hydrogen fuel.Bulk semiconductors generally suffer from...Solar-powered photocatalytic hydrogen production from water using semiconductors provides an eco-friendly and promising approach for converting solar energy into hydrogen fuel.Bulk semiconductors generally suffer from certain limitations,such as poor visible-light utilization,rapid recombination of charge carriers,and low catalytic capability.The key challenge is to develop visible-light-driven heterojunction photocatalysts that are stable and highly active during the water splitting process.Here,we demonstrate the integration of one-dimensional(1D)Cd S nanorods with two-dimensional(2D)1 T-phase dominated WS_(2) nanosheets for constructing mixed-dimensional heterojunctions for the photocatalytic hydrogen evolution reaction(HER).The resulting 1D CdS/2D WS_(2) nanoheterojunction exhibited an ultrahigh hydrogen-evolution activity of~70 mmol·g^(-1)·h^(-1) that was visible to the naked eye,as well as long-term stability under visible light illumination.The results reveal that the synergy of hybrid nanoarchitectures and intimate interfacial contact between the 1D Cd S nanorods and 1T-phase dominated 2D WS_(2) nanosheets facilitates charge carrier transport,which is beneficial for achieving superior hydrogen evolution.展开更多
Although MgH_(2) has been widely regarded as a promising material for solid-state hydrogen storage,its high operating temperature and slow kinetics pose a major bottleneck to its practical application.Here,a nanocompo...Although MgH_(2) has been widely regarded as a promising material for solid-state hydrogen storage,its high operating temperature and slow kinetics pose a major bottleneck to its practical application.Here,a nanocomposite catalyst with interfacial coupling and oxygen defects,Ni/CeO_(2),is fabricated to promote H_(2) desorption and absorption properties of MgH_(2).The interface of Ni/CeO_(2) contributes to both strong mechanical coupling towards stabilizing partial Ni and electronic coupling towards inducing a high con-centration of oxygen vacancies in CeO_(2).Theoretical calculations evidence that CeO_(2) with oxygen vacancy assist Ni in weakening the energy of Mg-H bond as well as enhancing the adsorption energy of Ni upon hydrogen atoms,and the extent of this assistance surprisingly increases with increasing oxygen vacancies concentration.As a result,an impressive performance is achieved by MgH_(2)-5 wt.%Ni/CeO_(2) with onset desorption temperature of only 165°C,and it absorbs approximately 80%hydrogen in just 800 s at 125°C.The generation mechanism of intermediate active species concerning Ni/CeO_(2) in different states has been analyzed for the first time,and the relationship between interfacial coupling and phase evolution has been elucidated.Therefore,a mechanism of the catalysis-assisting effect regarding oxygen defects is proposed.It is believed that this work provides a unique perspective on the mechanism of interfacial coupling and the generation of defects in composite catalysts.展开更多
A Monte Carlo simulated-annealing algorithm was used to study the magnetic state in an in-plane helimagnet layer on triangular lattice that exchange couples to an underlayer with strong out-of-plane anisotropy.In the ...A Monte Carlo simulated-annealing algorithm was used to study the magnetic state in an in-plane helimagnet layer on triangular lattice that exchange couples to an underlayer with strong out-of-plane anisotropy.In the single helimagnet layer with in-plane anisotropy(K),the formation of labyrinth-like domains with local spin spirals,instead of parallel stripes,is favored,and these domains rapidly transform into dense skyrmion crystals with increasing interfacial exchange coupling(J'),equivalent to a virtual magnetic field,and finally evolve to an out-of-plane uniform state at large enough J'.Moreover,with increasing K,the skyrmion crystal state can vary from regular 6-nearest-neighboring circular skyrmion arrangement to irregular squeezed skyrmions with less than 6 nearest neighbors when the in-plane anisotropy energy is higher than the interfacial exchange energy as the skyrmion number is maximized.Finally,we demonstrated that the antiferromagnetic underlayer cannot induce skyrmions while the chirality inversion can be achieved on top of an out-of-plane magnetization underlayer with 180°domain walls,supporting the experimental findings in FeGe thin film.This compelling advantage offers a fertile playground for exploring emergent phenomena that arise from interfacing magnetic skyrmions with additional functionalities.展开更多
The interstitial structure and weak Ni-N interaction of Ni3N lead to high unoccupied d orbital energy and unsuitable orbital orientation,which consequently results in weak orbital coupling with H2O and slow water diss...The interstitial structure and weak Ni-N interaction of Ni3N lead to high unoccupied d orbital energy and unsuitable orbital orientation,which consequently results in weak orbital coupling with H2O and slow water dissociation kinetics for alkaline hydrogen evolution catalysis.Herein,we successfully lower the unoccupied d orbital energy of Ni3N to strengthen the interfacial electronic coupling by employing the strong electron pulling capability of oxygen dopants.The prepared O-Ni3N catalyst delivers an overpotential of 55 mV at 10 mA cm−2,very close to the commercial Pt/C.Refined structural characterization indicates the oxygen incorporation can decrease the electron densities around the Ni sites.Moreover,density functional theory calculation further proves the oxygen incorporation can create more unoccupied orbitals with lower energy and superior orientation for water adsorption and dissociation.The concept of orbital-regulated interfacial electronic coupling could offer a unique approach for the rational design of hydrogen evolution catalysts and beyond.展开更多
The high unoccupied d band energy of Ni_(3)N basically results in weak orbital coupling with water molecule,consequently leading to slow water dissociation kinetics.Herein,we demonstrate Cr doping can downshift the un...The high unoccupied d band energy of Ni_(3)N basically results in weak orbital coupling with water molecule,consequently leading to slow water dissociation kinetics.Herein,we demonstrate Cr doping can downshift the unoccupied d orbitals and strengthen the interfacial orbital coupling to boost the water dissociation kinetics.The prepared Cr-Ni_(3)N/Ni displays an impressive overpotential of 37 mV at 10 mA·cmgeo-2,close to the benchmark Pt/C in 1.0 M KOH solution.Refined structural analysis reveals the Cr dopant exists as the Cr-N_(6)states and the average d band energy of Ni_(3)N is also lowered.Density functional theory calculation further confirms the downshifted d band energy can strengthen the orbital coupling between the unpaired electrons in O 2p and the unoccupied state of Ni 3d,which thus facilitates the water adsorption and dissociation.The work provides a new concept to achieve on-demand functions for hydrogen evolution catalysis and beyond,by regulating the interfacial orbital coupling.展开更多
Experimental design and response surface methodology(RSM) were used to optimize the modification of conditions for glass surface grafting with acrylamide(AM) monomer for preparation of a glass fiber reinforced pol...Experimental design and response surface methodology(RSM) were used to optimize the modification of conditions for glass surface grafting with acrylamide(AM) monomer for preparation of a glass fiber reinforced poly(vinylidene fluoride)(PVDF) composite membrane(GFRP-CM). The factors considered for experimental design were the UV(ultraviolet)-irradiation time, the concentrations of the initiator and solvent, and the kinds and concentrations of the silane coupling agent. The optimum operating conditions determined were UV-irradiation time of 25 min, an initiator concentration of 0–0.25 wt.%,solvent of N-Dimethylacetamide(DMAC), and silane coupling agent KH570 with a concentration of 7 wt.%. The obtained optimal parameters were located in the valid region and the experimental confirmation tests conducted showed good accordance between predicted and experimental values. Under these optimal conditions, the water absorption of the grafted modified glass fiber was improved from 13.6% to 23%; the tensile strength was enhanced and the peeling strength of the glass fiber reinforced PVDF composite membrane was improved by 23.7% and 32.6% with an AM concentration at 1 wt.% and 2 wt.%. The surface composition and microstructure of AM grafted glass fiber were studied via several techniques including Field Emission Scanning Electron Microscopy(FESEM), Fourier transform infrared spectroscopy-attenuated total reflectance(FTIR-ATR) and energy dispersive X-ray spectroscopy(EDX). The analysis of the EDX and FTIR-ATR results confirmed that the AM was grafted to the glass fiber successfully by detecting and proving the existence of nitrogen atoms in the GFRP-CM.展开更多
We investigate the modulation of magnetic anisotropy of thulium iron garnet(TmIG)films by interfaced Bi2Se3 thin films.High quality epitaxial growth of Bi2Se3 films has been achieved by molecular beam epitaxy on TmIG ...We investigate the modulation of magnetic anisotropy of thulium iron garnet(TmIG)films by interfaced Bi2Se3 thin films.High quality epitaxial growth of Bi2Se3 films has been achieved by molecular beam epitaxy on TmIG films.By the method of ferromagnetic resonance,we find that the perpendicular magnetic anisotropy(PMA)of TmIG can be greatly strengthened by the adjacent Bi2Se3 layer.Moreover,the competition between topological surface states and thickness dependent bulk states of Bi2Se3 gives rise to the modulation of PMA of the Bi2Se3/TmIG heterostructures.The interfacial interaction can be attributed to the enhanced exchange coupling between Fe^3+ions of TmIG mediated by topological surface electrons of Bi2Se3.展开更多
Hollow semiconductor nanostructures with direct Z-scheme heterojunction have significant advantages for photocatalytic reactions,and optimizing the interfacial charge transmission of Z-scheme heterojunction is the hin...Hollow semiconductor nanostructures with direct Z-scheme heterojunction have significant advantages for photocatalytic reactions,and optimizing the interfacial charge transmission of Z-scheme heterojunction is the hinge to achieve excellent solar conversion efficiency.In this work,tubular Ni_(1−x)Co_(x)S_(2)-CdS heterostructures with reinforced Z-scheme charge transmission were constructed through an In-metal-organic framework(MOF)templated strategy.The Z-scheme charge transfer mechanism was sufficiently confirmed by combining density functional theory(DFT)calculation,X-ray photoelectron spectroscopy(XPS),surface photovoltage spectroscopy(SPV),and radical testing results.Crucially,the use of sodium citrate complexant contributes to the formation of intimate heterointerface,and the Fermi level gap between CdS and NiS_(2)is enlarged through Co doping into NiS_(2),which enhances the built-in electric field and photo-carriers transmission driving force for Ni_(1−x)Co_(x)S_(2)-CdS heterojunction,resulting in an evidently promoted activity toward H2 evolution reaction(HER).Under visible-light(λ>400 nm)irradiation,the Ni_(1−x)Co_(x)S_(2)-CdS composite with 10 mol%Co doping and 80 wt.%CdS(NC_(0.10)S-80%CdS)achieved an outstanding HER rate up to 35.94 mmol·g^(−1)·h^(−1)(corresponding to the apparent quantum efficiency of 34.7%at 420 nm),approximately 76.4 times that of 3 wt.%Pt-loaded CdS and it is much superior to that of most CdS-based photocatalysts ever reported.Moreover,the good photocatalytic durability of Ni_(1−x)Co_(x)S_(2)-CdS heterostructures was validated by cycling and long-term HER tests.This work could inspire the development of high-performance Z-scheme heterojunction via optimizing the morphology and interfacial charge transmission.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 22371165, 21971143, 22209098)the Natural Science Foundation of Hubei Province (No. 2022CFB326)+3 种基金the 111 Project (No. D20015)ITOYMR in the Higher Education Institutions of Hubei Province (No. T201904)the Key Project Foundation of Hubei Three Gorges Laboratory (No. Z2022078)the Opening Foundation of Hubei Three Gorges Laboratory (No. SK213002)。
文摘Constructing high-performance electrocatalysts for oxygen evolution reaction(OER) using a simple and economical strategy is considerably meaningful yet still challenging. Herein, Co(OH)_(2)/Mo_(2)Ti C_(2)T_(x)(where Txrepresents the surface functional groups,-O,-OH and-F) hetero-nanosheets were facilely prepared by the in situ topochemical transformation at room temperature towards efficient OER. The integrity of Co(OH)_(2)nanosheets and Mo_(2)Ti C_(2)T_(x) nanosheets affords interfacial coupling to optimize the electronic structures of Co and Mo ions, which endows the high electron transfer efficiency and rapid reaction kinetics. As a result, the Co(OH)_(2)/Mo_(2)Ti C_(2)T_(x) hetero-nanosheets exhibit excellent OER performances with low overpotentials of 283 m V on glass-carbon electrode, and 227 m V on nickel foam at 10 m A/cm^(2). Furthermore, the decent anti-alkali ability underpins superior operational stability exceeding 100 h, demonstrating grand potential in practical applications. This work provides a new insight for the synthesis of efficient and cost-effective two-dimensional(2D) material-based electrocatalysts.
基金financially supported by the National Natural Science Foundation of China(No.51762021)the Natural Science Foundation of Jiangxi province(Nos.20224ACB204008,20242BAB25223,and 20242BAB25248)the Special Funding Program for Graduate Student Innovation of Jiangxi Province(No.YC2024-S594)。
文摘Optimizing the interfacial environments of electrodes has emerged as an effective strategy to improve their electrochemical properties.Amorphous/crystalline interfacial coupling can effectively utilize the advantages of amorphous materials to optimize the interfacial structure for efficient Na^(+)storage.Herein,the dense homologous amorphous/crystalline heterointerfaces are in situ achieved in N-doped carbon nanobundles via self-polymerization and precise nitriding(Mo–N/Mo_(2)N@C).The amorphous Mo–N rich in unsaturated vacancy defects provides abundant active sites with isotropic ion-transport channels,and can effectively alleviate structural stress from crystalline Mo_(2)N.Meanwhile,the conductive Mo_(2)N can facilitate effective electron transfer,augmented further by the carbon encapsulation.Theoretical calculations reveal that the dense heterointerfaces can optimize the electronic structure and shift the d-p orbital centers of Mo and N upward,thereby enhancing the adsorption and mobility of Na^(+),and ultimately improving the charge transport and storage efficiency of the electrode.The Mo–N/Mo_(2)N@C as an anode delivers a 46.9%increase in reversible capacity over Mo_(2)N@C,reaching 461.1 m Ah.g^(–1)at 0.1 A.g^(–1),along with improved rate capability and cycling stability,underlining its practical utility.These results suggest that the homologous interfacial coupling can boost the storage properties of nitrides,providing a valuable reference for improving the properties of electrodes with low theoretical capacities.
基金Financial support from the National Natural Science Foundation of China(52302317)is gratefully acknowledged。
文摘Rechargeable magnesium batteries(RMBs)have garnered significant attention in energy storage applications due to their high capacity,low cost,and high safety.However,the strong polarization effect and slow kinetic de-intercalation of Mg^(2+)in the cathode limit their commercial application.This study presents a novel interface-coupled V_(2)CT_(x)@VS_(4)heterostructure through a one-step hydrothermal process.In this architecture,V_(2)CT_(x)and VS_(4)can mutually support their structural framework,which effectively prevents the structural collapse of V_(2)CT_(x)MXene and the aggregation of VS_(4).Crucially,interfacial coupling between V_(2)CT_(x)and VS_(4)induces strong V-S bonds,substantially enhancing structural stability.Benefiting from these advantages,the heterostructure exhibits high specific capacity(226 mAh g^(-1)at 100 mA g^(-1))and excellent long-cycle stability(89% capacity retention after 1000 cycles at 500 mA g^(-1)).Furthermore,the Mg^(2+)storage mechanism in the V_(2)CT_(x)@VS_(4)composite was elucidated through a series of ex-situ characterizations.This work provides a feasible strategy for designing V_(2)CT_(x)MXene-based cathodes with high capacity and extended cyclability for RMBs.
基金Projects(41977129,21607176,42007138) supported by the National Natural Science Foundation of ChinaProject(kq1802011) supported by the Changsha Outstanding Innovative Youth Training Program,ChinaProject(2017JJ3516)supported by the Natural Science Foundation of Hunan Province,China。
文摘A series of In_(x)Sb_(2-x)S_(3) nanosheets modified g-C_(3)N_(4)(In_(x)Sb_(2-x)S_(3)-TCN)heterojunctions with different g-C_(3)N_(4) contents were fabricated by an in situ deposition method.All the In_(x)Sb_(2-x)S_(3)-TCN composites were applied as photocatalysts in Cr(Ⅵ)polluted water treatment and the results displayed that In_(x)Sb_(2-x)S_(3)-TCN could effectively remove Cr(Ⅵ)under visible light through synergistic effects of adsorption and photocatalytic reduction.Especially,In_(x)Sb_(2-x)S_(3)-TCN-70(70 mg g-C_(3)N_(4)) exhibited the most excellent adsorption and photocatalytic reduction performance among all composites,which possessed a high equilibrium adsorption capacity of 12.45 mg/g in a 30.0 mg/L Cr(Ⅵ)aqueous solution,and reduced Cr(Ⅵ)to Cr(Ⅲ)within 10 min under visible light irradiation.DRS and PL results indicated that the interfacial coupling effect between g-C_(3)N_(4)and In_(x)Sb_(2-x)S_(3) enhanced the utilization efficiency of visible light and suppressed photoinduced carrier recombination,which improved the photocatalytic activity of composites.Moreover,the photocatalyst exhibited satisfactory reduction activity and good stability after 5 cycles of Cr(Ⅵ)adsorptionphotoreduction.
基金supported by the National Natural Science Foundation of China(NSFC)under grant No.51902155the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mechanism and the interfacial coupling in Bi_(0.5)Na_(0.5)TiO_(3)/SrTiO_(3)(BNT/STO)heterointerfaces are investigated by the aberration-corrected scanning transmission electron microscopy,which is synthesized by a hydrothermal method.The results illustrate that 4 mol/L NaOH leads to not only the epitaxial growth of the BNT film but also the mutual diffusion of elements.The uneven distribution of local elements in BNT films is observed and confirmed to impact the cation displacements of B-site and lattice distortion.However,the overall trend of B-site cation displacement at the BNT/STO heterointerfaces is dominated by the interfacial strain.Additionally,the oxygen octahedral tilt exhibits continuous tilt patterns of a^(0)a^(0)a^(0)-a−b^(0)c−-a^(0)a^(0)c−-a^(0)b−c−-a−b−c−from the substrate to BNT film due to the constraint of the substrate and presents a strong correlation with cation displacement.These results are helpful to understand the underlying atomic structures and physical properties of BNT epitaxial thin films.
基金supported by the National Natural Science Foundation of China (No. 51802177)Independent Cultivation Program of Innovation Team of Ji nan City (No. 2019GXRC011)Introduction and Cultivation Plan of Young Innovative Talents in Colleges and Universities of Shandong Province,Shandong Provincial Natural Science Foundation (No. ZR^(2)020ME052)。
文摘Developing efficient electrocatalysts for hydrogen evolution reaction(HER) is of great importance in contemporary water electrolysis technology. Here, a novel hierarchically sea urchin-like electrocatalyst(Mo_(4)O_(11)-MoS_(2)-VO_(2)) is synthesized by hydrothermal deposition and post-annealing strategy. The optimized electrocatalyst behaves as a high active hydrogen evolution electrode in 0.5 mol/L H_(2)SO_(4). This electrode needs overpotential of only 43 m V to achieve 10 m A/cm^(2)with a Tafel slope of 37 m V/dec and maintains its catalytic activity for at least 36 h. Better than most previously reported non-noble metal electrocatalysts anchored on carbon cloth. It is worth mentioning that the hierarchical sea urchin-like structure promotes the redistribution of electrons and provides more catalytic active sites. This strategy shows a way for the construction of inexpensive non-noble metal electrocatalysts in the future.
基金Project supported by the National Natural Science Foundation of China(Grant No.1374195)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2014AM017)the Excellent Young Scholars Research Fund of Shandong Normal University,China
文摘The effect of interfacial coupling on rectification in an organic co-oligomer spin diode is investigated theoretically by considering spin-independent and spin-resolved couplings respectively. In the case of spin-independent coupling, an optimal interfacial coupling strength with a significant enhanced rectification ratio is found, whose value depends on the structural asymmetry of the molecule. In the case of spin-resolved coupling, we found that only the variation of the interfacial coupling with specific spin is effective to modulate the rectification, which is due to the spin-filtering property of the central asymmetric magnetic molecule. A transition of the spin-current rectification between parallel spin-current rectification and antiparallel spin-current rectification may be observed with the variation of the spin-resolved interfacial coupling. The interfacial effect on rectification is further analyzed from the spin-dependent transmission spectrum at different biases.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2017YFA0303603 and 2016YFA0401803)the National Natural Science Foundation of China(Grant Nos.U2032218,11574316,11874120,61805256,and 11904367)+1 种基金the Plan for Major Provincial Science&Technology Project(Grant No.202003a05020018)the Key Research Program of Frontier Sciences,CAS(Grant No.QYZDB-SSW-SLH011)。
文摘The magnetic anisotropy manipulation in the Sm_(3)Fe_(5)O_(12)(SmIG)films and its effect on the interfacial spin coupling in the CoFe/SmIG heterostructures were studied carefully.By switching the orientation of the Gd_(3)Ga_(5)O_(12)substrates from(111)to(001),the magnetic anisotropy of obtained SmIG films shifts from in-plane to out-of-plane.Similar results can also be obtained in the films on Gd_(3)Ga_(5)O_(12)substrates,which identifies the universality of such orientation-induced magnetic anisotropy switching.Additionally,the interfacial spin coupling and magnetic anisotropy switching effect on the spin wave in CoFe/SmIG magnetic heterojunctions have also been explored by utilizing the time-resolved magneto-optical Kerr effect technique.It is intriguing to find that both the frequency and effective damping factor of spin precession in CoFe/SmIG heterojunctions can be manipulated by the magnetic anisotropy switching of SmIG films.These findings not only provide a route for the perpendicular magnetic anisotropy acquisition but also give a further path for spin manipulation in magnetic films and heterojunctions.
基金supported by National Key R&D Program of China(No.2024YFB3614404)Key Scientific Research Plan of Education Department of Shannxi(No.23JY035)+1 种基金the National Natural Science Foundation of China(No.62105256)Shaanxi Province Natural Science Basic Research Programme(No.2024JCYBMS-523).
文摘Carrier transport in colloidal quantum dot(CQD)films is strongly influenced by the interfacial coupling between CQDs.Currently,the shape of PbS CQDs synthesized using traditional methods results in random orientation relationships between the crystal facets in CQD films,limiting the coupling strength and the final performance of optoelectronic devices.In this study,post-synthesis surface treatment of PbS CQDs was employed to achieve facet control during secondary growth,manipulating the facets of PbS CQDs at the nanoscale to enhance interfacial coupling within CQD films.Additionally,mixed ligands of PbX_(2)(X=Br,I)and anhydrous sodium acetate were used to passivate the PbS CQDs,ensuring sufficient passivation.This method combines facet passivation with strong coupling through the(100)facets of CQDs,thereby enhancing carrier mobility and improving device performance.Experimental results showed that,compared to standard PbS CQD films,the electron and hole mobilities of the PbS CQD films subjected to secondary growth were significantly improved,with hole mobility increased by 6 times.Photodetectors fabricated using these films achieved a quantum efficiency of 33%at 1500 nm under 0 V bias,a threefold improvement compared to standard devices.
基金supported by the Chinese Academy of Sciences Project for Young Scientists in Basic Research(Grant No.YSBR-049)the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302800)the Fundamental Research Funds for the Central Universities(Grant No.WK3510000013)。
文摘Recent advances in van der Waals(vdW) ferroelectrics have sparked the development of related heterostructures with non-volatile and field-tunable functionalities. In vdW ferroelectric heterojunctions, the interfacial electrical characteristics play a crucial role in determining their performance and functionality. In this study,we explore the interfacial polarization coupling in two-dimensional(2D) ferroelectric heterojunctions by fabricating a graphene/h-BN/CuInP_(2)S_(6)/α-In_(2)Se_(3)/Au ferroelectric field-effect transistor. By varying the gate electric field, the CuInP_(2)S_(6)/α-In_(2)Se_(3) heterojunction displays distinct interfacial polarization coupling states, resulting in significantly different electrical transport behaviors. Under strong gate electric fields, the migration of Cu ions further enhances the interfacial polarization effect, enabling continuous tuning of both the polarization state and carrier concentration in α-In_(2)Se_(3). Our findings offer valuable insights for the development of novel multifunctional devices based on 2D ferroelectric materials.
基金The authors appreciate the supports from the National Research Foundation(NRF),Prime Minister’s Office,Singapore,under its Campus for Research Excellence and Technological Enterprise(CREATE)programme.We also acknowledge financial support from the academic research fund AcRF tier 2(M4020246,ARC10/15),Ministry of Education,Singapore.
文摘Tuning and optimization of electronic structures and related reaction energetics are critical toward the rational design of efficient electrocatalysts.Herein,experimental and theoretical calculation demonstrate the originally inert N site within polyaniline(PANI)can be activated for hydrogen evolution by proper d-πinterfacial electronic coupling with metal oxide.As a result,the assynthesized WO3 assemblies@PANI via a facile redox-induced assembly and in situ polymerization,exhibits the electrocatalytic production of hydrogen better than other control samples including W18O49@PANI and most of the reported nobel-metal-free electrocatalysts,with low overpotential of 74 mV at 10 mA·cm−2 and small Tafel slope of 46 mV·dec−1 in 0.5M H2SO4(comparable to commercial Pt/C).The general efficacy of this methodology is also validated by extension to other metal oxides such as MoO3 with similar improvements.
基金financially supported by the National Natural Science Foundation of China(21922811,51702284,and 21878270)Zhejiang Provincial Natural Science Foundation of China(LR19B060002)the Startup Foundation for Hundred-Talent Program of Zhejiang University.
文摘Cost-effective and stable electrocatalysts with ultra-high current densities for electrochemical oxygen evolution reaction(OER)are critical to the energy crisis and environmental pollution.Herein,we report a superaerophobic three dimensional(3D)heterostructured nanowrinkles of bimetallic selenides consisting of crystalline NiSe2 and NiFe2Se4 grown on NiFe alloy(NiSe2/NiFe2Se4@NiFe)prepared by a thermal selenization procedure.In this unique 3D heterostructure,numerous nanowrinkles of NiSe2/NiFe2Se4 hybrid with a thickness of ~100 nm are grown on NiFe alloy in a uniform manner.Profiting by the large active surface area and high electronic conductivity,the superaerophobic NiSe2/NiFe2Se4@NiFe heterostructure exhibits excellent electrocatalytic activity and durability towards OER in alkaline media,outputting the low potentials of 1.53 and 1.54 V to achieve ultra-high current densities of 500 and 1000 mA cm^−2,respectively,which is among the most active Ni/Fe-based selenides,and even superior to the benchmark Ir/C catalyst.The in-situ derived FeOOH and NiOOH species from NiSe2/NiFe2Se4@NiFe are deemed to be efficient active sites for OER.
文摘Solar-powered photocatalytic hydrogen production from water using semiconductors provides an eco-friendly and promising approach for converting solar energy into hydrogen fuel.Bulk semiconductors generally suffer from certain limitations,such as poor visible-light utilization,rapid recombination of charge carriers,and low catalytic capability.The key challenge is to develop visible-light-driven heterojunction photocatalysts that are stable and highly active during the water splitting process.Here,we demonstrate the integration of one-dimensional(1D)Cd S nanorods with two-dimensional(2D)1 T-phase dominated WS_(2) nanosheets for constructing mixed-dimensional heterojunctions for the photocatalytic hydrogen evolution reaction(HER).The resulting 1D CdS/2D WS_(2) nanoheterojunction exhibited an ultrahigh hydrogen-evolution activity of~70 mmol·g^(-1)·h^(-1) that was visible to the naked eye,as well as long-term stability under visible light illumination.The results reveal that the synergy of hybrid nanoarchitectures and intimate interfacial contact between the 1D Cd S nanorods and 1T-phase dominated 2D WS_(2) nanosheets facilitates charge carrier transport,which is beneficial for achieving superior hydrogen evolution.
基金the National Natural Science Foundation of China(Nos.52071177 and 52171214)National Key R&D Program of China(No.2022YFB3803801)+1 种基金Postgrad-uate Research Practice Innovation Program of Jiangsu Province(No.KYCX22-1289)the Priority Academic Program Development (PAPD) of J iangsu Higher Education Institutions . The computational resources generously provided by the High Performance Comput- ing Center of Nanjing Tech University are greatly appreciated.
文摘Although MgH_(2) has been widely regarded as a promising material for solid-state hydrogen storage,its high operating temperature and slow kinetics pose a major bottleneck to its practical application.Here,a nanocomposite catalyst with interfacial coupling and oxygen defects,Ni/CeO_(2),is fabricated to promote H_(2) desorption and absorption properties of MgH_(2).The interface of Ni/CeO_(2) contributes to both strong mechanical coupling towards stabilizing partial Ni and electronic coupling towards inducing a high con-centration of oxygen vacancies in CeO_(2).Theoretical calculations evidence that CeO_(2) with oxygen vacancy assist Ni in weakening the energy of Mg-H bond as well as enhancing the adsorption energy of Ni upon hydrogen atoms,and the extent of this assistance surprisingly increases with increasing oxygen vacancies concentration.As a result,an impressive performance is achieved by MgH_(2)-5 wt.%Ni/CeO_(2) with onset desorption temperature of only 165°C,and it absorbs approximately 80%hydrogen in just 800 s at 125°C.The generation mechanism of intermediate active species concerning Ni/CeO_(2) in different states has been analyzed for the first time,and the relationship between interfacial coupling and phase evolution has been elucidated.Therefore,a mechanism of the catalysis-assisting effect regarding oxygen defects is proposed.It is believed that this work provides a unique perspective on the mechanism of interfacial coupling and the generation of defects in composite catalysts.
基金The authors express their thanks to Dr.Gong Chen helping with this work.This work was financially supported by the National Natural Science Foundation of China(No.11774045)the Joint Research Fund Liaoning Shenyang National Laboratory for Materials Science(No.20180510008)the Fundamental Research Funds for Central Universities(No.N182410008-1)。
文摘A Monte Carlo simulated-annealing algorithm was used to study the magnetic state in an in-plane helimagnet layer on triangular lattice that exchange couples to an underlayer with strong out-of-plane anisotropy.In the single helimagnet layer with in-plane anisotropy(K),the formation of labyrinth-like domains with local spin spirals,instead of parallel stripes,is favored,and these domains rapidly transform into dense skyrmion crystals with increasing interfacial exchange coupling(J'),equivalent to a virtual magnetic field,and finally evolve to an out-of-plane uniform state at large enough J'.Moreover,with increasing K,the skyrmion crystal state can vary from regular 6-nearest-neighboring circular skyrmion arrangement to irregular squeezed skyrmions with less than 6 nearest neighbors when the in-plane anisotropy energy is higher than the interfacial exchange energy as the skyrmion number is maximized.Finally,we demonstrated that the antiferromagnetic underlayer cannot induce skyrmions while the chirality inversion can be achieved on top of an out-of-plane magnetization underlayer with 180°domain walls,supporting the experimental findings in FeGe thin film.This compelling advantage offers a fertile playground for exploring emergent phenomena that arise from interfacing magnetic skyrmions with additional functionalities.
基金This work was supported by the National Natural Science Foundation of China(21771169,51801075,11722543)the National Key Research and Development Program of China(2017YFA0206703)+1 种基金Anhui Provincial Natural Science Foundation(BJ2060190077)Recruitment Program of Global Expert,and the Fundamental Research Funds for the Central Universities(WK2060190074,WK2060190081,WK2310000066).
文摘The interstitial structure and weak Ni-N interaction of Ni3N lead to high unoccupied d orbital energy and unsuitable orbital orientation,which consequently results in weak orbital coupling with H2O and slow water dissociation kinetics for alkaline hydrogen evolution catalysis.Herein,we successfully lower the unoccupied d orbital energy of Ni3N to strengthen the interfacial electronic coupling by employing the strong electron pulling capability of oxygen dopants.The prepared O-Ni3N catalyst delivers an overpotential of 55 mV at 10 mA cm−2,very close to the commercial Pt/C.Refined structural characterization indicates the oxygen incorporation can decrease the electron densities around the Ni sites.Moreover,density functional theory calculation further proves the oxygen incorporation can create more unoccupied orbitals with lower energy and superior orientation for water adsorption and dissociation.The concept of orbital-regulated interfacial electronic coupling could offer a unique approach for the rational design of hydrogen evolution catalysts and beyond.
基金The work was supported by the National Natural Science Foundation of China(Nos.21771169 and 11722543)the National Key Research and Development Program of China(No.2017YFA0206703)+1 种基金Anhui Provincial Natural Science Foundation(No.BJ2060190077)Collaborative Innovation Program of Hefei Science Center,CAS,and the Fundamental Research Funds for the Central Universities(Nos.WK2060190074,WK2060190081,WK2310000066,and WK2060000015).
文摘The high unoccupied d band energy of Ni_(3)N basically results in weak orbital coupling with water molecule,consequently leading to slow water dissociation kinetics.Herein,we demonstrate Cr doping can downshift the unoccupied d orbitals and strengthen the interfacial orbital coupling to boost the water dissociation kinetics.The prepared Cr-Ni_(3)N/Ni displays an impressive overpotential of 37 mV at 10 mA·cmgeo-2,close to the benchmark Pt/C in 1.0 M KOH solution.Refined structural analysis reveals the Cr dopant exists as the Cr-N_(6)states and the average d band energy of Ni_(3)N is also lowered.Density functional theory calculation further confirms the downshifted d band energy can strengthen the orbital coupling between the unpaired electrons in O 2p and the unoccupied state of Ni 3d,which thus facilitates the water adsorption and dissociation.The work provides a new concept to achieve on-demand functions for hydrogen evolution catalysis and beyond,by regulating the interfacial orbital coupling.
基金supported by the financial support of the National Natural Science Foundation of China (No. 51278483)the Institute of Chinese Academy of Sciences in cooperation projects (No. ZNGZ2011023)the Daqi Technology of Beijing Co. Ltd. (No. 04F0261601)
文摘Experimental design and response surface methodology(RSM) were used to optimize the modification of conditions for glass surface grafting with acrylamide(AM) monomer for preparation of a glass fiber reinforced poly(vinylidene fluoride)(PVDF) composite membrane(GFRP-CM). The factors considered for experimental design were the UV(ultraviolet)-irradiation time, the concentrations of the initiator and solvent, and the kinds and concentrations of the silane coupling agent. The optimum operating conditions determined were UV-irradiation time of 25 min, an initiator concentration of 0–0.25 wt.%,solvent of N-Dimethylacetamide(DMAC), and silane coupling agent KH570 with a concentration of 7 wt.%. The obtained optimal parameters were located in the valid region and the experimental confirmation tests conducted showed good accordance between predicted and experimental values. Under these optimal conditions, the water absorption of the grafted modified glass fiber was improved from 13.6% to 23%; the tensile strength was enhanced and the peeling strength of the glass fiber reinforced PVDF composite membrane was improved by 23.7% and 32.6% with an AM concentration at 1 wt.% and 2 wt.%. The surface composition and microstructure of AM grafted glass fiber were studied via several techniques including Field Emission Scanning Electron Microscopy(FESEM), Fourier transform infrared spectroscopy-attenuated total reflectance(FTIR-ATR) and energy dispersive X-ray spectroscopy(EDX). The analysis of the EDX and FTIR-ATR results confirmed that the AM was grafted to the glass fiber successfully by detecting and proving the existence of nitrogen atoms in the GFRP-CM.
基金Project supported by the National Key Basic Research Project of China(Grant No.2016YFA0300600)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB33020300)the National Natural Science Foundation of China(Grant Nos.11604375 and 11874416)。
文摘We investigate the modulation of magnetic anisotropy of thulium iron garnet(TmIG)films by interfaced Bi2Se3 thin films.High quality epitaxial growth of Bi2Se3 films has been achieved by molecular beam epitaxy on TmIG films.By the method of ferromagnetic resonance,we find that the perpendicular magnetic anisotropy(PMA)of TmIG can be greatly strengthened by the adjacent Bi2Se3 layer.Moreover,the competition between topological surface states and thickness dependent bulk states of Bi2Se3 gives rise to the modulation of PMA of the Bi2Se3/TmIG heterostructures.The interfacial interaction can be attributed to the enhanced exchange coupling between Fe^3+ions of TmIG mediated by topological surface electrons of Bi2Se3.
基金supported by the National Natural Science Foundation of China(Nos.22179068,52272222,52072197,and 52171140)the 111 Project of China(No.D20017)+5 种基金the Natural Science Foundation of Shandong Province(No.ZR2019JQ14)the Major Scientific and Technological Innovation Project of Shandong Province(No.2019JZZY020405)the Key Research and Development Program of Jiangsu Province(No.BE2021070)the Scientific and Technological Innovation Promotion Project for Small-medium Enterprises of Shandong Province(No.2022TSGC1257)the Shandong Province“Double-Hundred Talent Plan”(Nos.WST2019011,WST2020003,and WST2021021)the Major Research Program of Jining City(No.2020ZDZP024).
文摘Hollow semiconductor nanostructures with direct Z-scheme heterojunction have significant advantages for photocatalytic reactions,and optimizing the interfacial charge transmission of Z-scheme heterojunction is the hinge to achieve excellent solar conversion efficiency.In this work,tubular Ni_(1−x)Co_(x)S_(2)-CdS heterostructures with reinforced Z-scheme charge transmission were constructed through an In-metal-organic framework(MOF)templated strategy.The Z-scheme charge transfer mechanism was sufficiently confirmed by combining density functional theory(DFT)calculation,X-ray photoelectron spectroscopy(XPS),surface photovoltage spectroscopy(SPV),and radical testing results.Crucially,the use of sodium citrate complexant contributes to the formation of intimate heterointerface,and the Fermi level gap between CdS and NiS_(2)is enlarged through Co doping into NiS_(2),which enhances the built-in electric field and photo-carriers transmission driving force for Ni_(1−x)Co_(x)S_(2)-CdS heterojunction,resulting in an evidently promoted activity toward H2 evolution reaction(HER).Under visible-light(λ>400 nm)irradiation,the Ni_(1−x)Co_(x)S_(2)-CdS composite with 10 mol%Co doping and 80 wt.%CdS(NC_(0.10)S-80%CdS)achieved an outstanding HER rate up to 35.94 mmol·g^(−1)·h^(−1)(corresponding to the apparent quantum efficiency of 34.7%at 420 nm),approximately 76.4 times that of 3 wt.%Pt-loaded CdS and it is much superior to that of most CdS-based photocatalysts ever reported.Moreover,the good photocatalytic durability of Ni_(1−x)Co_(x)S_(2)-CdS heterostructures was validated by cycling and long-term HER tests.This work could inspire the development of high-performance Z-scheme heterojunction via optimizing the morphology and interfacial charge transmission.