The gradient doping regions were employed in the emitter layer and the base layer of GaAs based laser power converters(LPCs).Silvaco TCAD was used to numerically simulate the linear gradient doping and exponential gra...The gradient doping regions were employed in the emitter layer and the base layer of GaAs based laser power converters(LPCs).Silvaco TCAD was used to numerically simulate the linear gradient doping and exponential gradient doping structure,and analyze the transport process of photogenerated carriers.Energy band adjustment via gradient doping improved the separation and transport efficiency of photogenerated carriers and reduced the total recombination rate of GaAs LPCs.Compared with traditional structure of LPCs,the photoelectric conversion efficiency of LPCs with linear and exponential gradient doping structure were improved from 52.7%to 57.2%and 57.7%,respectively,under 808 nm laser light at the power density of 1 W/cm^(2).展开更多
CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hi...CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hindered by poor charge separation efficiency.Herein,we introduce a characteristic in-situ solution Fe-doping strategy that markedly improves photoelectrochemical performance of CBO,doubling the photocurrent density and achieving an unprecedented 190 mV anodic shift in the onset potential.By integrating with an electrochemical oxidation post-treatment,a record incident photon-to-current efficiency(IPCE)exceeding 40% at 0.6 V vs.RHE under visible light illumination is achieved.The versatility of the doping strategy is demonstrated across CBO photocathodes synthesized by different methods with various morphologies,grain sizes,and crystallinities.Mechanistic studies reveal that the gradient distribution of Fe^(3+)ions generates an internal electric field that facilitates efficient charge separation and increases acceptor density.The strong Fe-O bonding also enhances structural stability against photoinduced corrosion.Notably,our investigation uncovers the non-temperature-dependent nature of CBO photocurrent,indicating that PEC performance enhancement primarily depends on reducing carrier recombination rather than improving bulk conductivity.This work lays the groundwork for future advancements in water splitting performance of CBO photocathodes,offering a complementary strategy to conventional methods for enhancing charge separation efficiency.展开更多
The gradient-doping structure is first applied to prepare the transmission-mode GaAs photocathode and the integral sensitivity of the sealed image tube achieves 1420μA/lm. This paper studies the inner carrier concent...The gradient-doping structure is first applied to prepare the transmission-mode GaAs photocathode and the integral sensitivity of the sealed image tube achieves 1420μA/lm. This paper studies the inner carrier concentration distribution of the gradient-doping transmission-mode GaAs photocathode after molecular beam epitaxy （MBE） growth using the electrochemical capacitance-voltage profiling. The results show that an ideal gradient-doping structure can be obtained by using MBE growth. The total band-bending energy in the gradient-doping GaAs active-layer with doping concentration ranging from 1×10^19 cm-3 to 1×1018 cm-3 is calculated to be 46.3 meV, which helps to improve the photoexcited electrons movement toward surface for the thin epilayer. In addition,by analysis of the band offsets, it is found that the worse carrier concentration discrepancy between GaAs and GaA1As causes a lower back interface electron potential barrier which decreases the amount of high-energy photoelectrons and affects the short-wave response.展开更多
Ceramic fuel cells hold an important position for the sustainable energy future using renewable energy sources with high efficiency.The design and synthesis of active materials,interface engineering and having capabil...Ceramic fuel cells hold an important position for the sustainable energy future using renewable energy sources with high efficiency.The design and synthesis of active materials,interface engineering and having capability of low operating temperature is considered as an important factor to further increase the power output and stability of ceramic fuel cell devices.A novel methodology has vital importance to develop new functionalities of existing materials by introducing new different effects.The built-in electric field(BIEF) is one of the most recently used approaches to improve charge transfer and ionic conductivity of solid oxide materials.Herein,we demonstrate gradient doping strategy in CeO_(2)-δstructure to produce BIEF effect and to modulate the proton transport effectively at the surface layer rather than bulk structure.The inclusions of La and Sr metal ions at the surface and Co-metal ions into bulk-layer of CeO_(2)form the gradiently doped structure.The gradient doping into CeO_(2)highly improves the proton transport properties through the surface layer by modifying the energy levels.Moreover,unbalanced charge distribution due to gradient doping produces built-in electric-field to provide extra driving force for protons transport through surface layer.The acquired gradiently doped fluorite structure exhibits remarkable proton conductivity of>0.2 S/cm,as a result ceramic fuel cell shows power output of>1000 mW/cm2while operating at 500℃.This unique work highlights the critical role of gradiently doped electrolyte in electrochemical conversion energy devices and offers new understanding and practices for sustainable energy future.展开更多
Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capac...Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capacity fading.Herein,the dual-strategy of Cr,B complex coating and local gradient doping is simultaneously achieved on LLO surface by a one-step wet chemical reaction at room temperature.Density functional theory(DFT)calculations prove that stable B-O and Cr-O bonds through the local gradient doping can significantly reduce the high-energy O 2p states of interfacial lattice O,which is also effective for the near-surface lattice O,thus greatly stabilizing the LLO surface,Besides,differential electrochemical mass spectrometry(DEMS)indicates that the Cr_(x)B complex coating can adequately inhibit oxygen release and prevents the migration or dissolution of transition metal ions,including allowing speedy Li^(+)migration,The voltage and capacity fading of the modified cathode(LLO-C_(r)B)are adequately suppressed,which are benefited from the uniformly dense cathode electrolyte interface(CEI)composed of balanced organic/inorganic composition.Therefore,the specific capacity of LLO-CrB after 200 cycles at 1C is 209.3 mA h g^(-1)(with a retention rate of 95.1%).This dual-strategy through a one-step wet chemical reaction is expected to be applied in the design and development of other anionic redox cathode materials.展开更多
Increasing the charging cut-off voltage can significantly enhance the energy density of LiCoO_(2).However,the continuous deterioration of interface structure and transport kinetics under high voltage poses challenges ...Increasing the charging cut-off voltage can significantly enhance the energy density of LiCoO_(2).However,the continuous deterioration of interface structure and transport kinetics under high voltage poses challenges to electrochemical stability.This work proposes to in-situ construct a uniform element gradient modification structure on the surface and subsurface of LiCoO_(2).The modification structure contains an Sb_(2)O_(3)&SbF_(x)composite coating layer and an Sb-F doped spinel-like transition layer,simultaneously.The modified sample maintains an initial discharge specific capacity of 221.2 mA h g^(-1)and a capacity retention of 86%after 200 cycles at 3–4.6 V and 0.5 C.Moreover,it has a discharge specific capacity of163.3 mA h g^(-1)at a high rate of 5 C.Meanwhile,combining highly electronegative Sb^(3+)&F^(-)that widen the Li^(+)transport channel with the amorphous coating of F^(-)doped Sb_(2)O_(3)with higher conductivity improves the interface transport kinetics.This breaks the stereotypical view in traditional concepts that fluorinated coatings or inert metal oxide coatings inhibit Li^(+)transport.Moreover,the inert composite coating combined with Sb–O–F with high bond energy stabilizes the surface structure.A series of characterizations confirm that the joint improvement of interface structure stability and transport kinetics significantly enhances the electrochemical performance of LiCoO_(2).展开更多
The construction of a homojunction is an effective approach for addressing issues such as slow charge separation and charge-transfer kinetics in photoanodes.In the present work,we designed a gradient Si-and Ti-doped F...The construction of a homojunction is an effective approach for addressing issues such as slow charge separation and charge-transfer kinetics in photoanodes.In the present work,we designed a gradient Si-and Ti-doped Fe_(2)O_(3) homojunction photoanode to improve the photoelectrochemical(PEC)performance of a Ti-doped Fe_(2)O_(3) photoanode.Ti-FeOOH nanocorals were synthesized using a hydrothermal process,and Si-FeOOH was grown on Ti-FeOOH nanocorals using a rapid and facile microwaveassisted(MW)technique.By varying the MW irradiation time,the thickness of the Si/Ti:Fe_(2)O_(3) photoanode was adjusted and an optimized 3-Si/Ti:Fe_(2)O_(3) photoelectrode was achieved with a significantly enhanced photocurrent density(1.37 mA cm^(-2) at 1.23 V vs.RHE)and a cathodic shift of the onset potential(150 mV)compared with that of bare Ti-Fe_(2)O_(3).This enhanced PEC performance can be ascribed to homojunction formation and Si gradient doping.The Si dopant increased the donor concentration and the formation of a homojunction improved the intrinsic built-in electric field,thereby promoting charge separation and charge transfer.Furthermore,the as-formed homojunction passivated the surfacetrapping states,consequently improving the charge transfer efficiency(60%at 1.23 VRHE)at the photoanode/electrolyte interface.These findings could pave the way for the microwave-assisted fabrication of diverse efficient homojunction photoanodes for PEC water splitting applications.展开更多
A branched core-shell nanosphere composed of an anatase TiO_(2)(a-TiO_(2)) core and a TiO_(2)nanobranch shell with gradient-doped N(a-TiO_(2)@N-TiO_(2)) is synthesized by a simple in situ doping method, in which mixed...A branched core-shell nanosphere composed of an anatase TiO_(2)(a-TiO_(2)) core and a TiO_(2)nanobranch shell with gradient-doped N(a-TiO_(2)@N-TiO_(2)) is synthesized by a simple in situ doping method, in which mixed crystal anatase-rutile TiO_(2)(ar-TiO_(2)) nanosphere is first prepared by oxidizing Ti using H_(2)O_(2), and then is etched by NH_(3)·H_(2)O to form(NH_(4))2TiO_(3)nanobranches, which is converted into a-TiO_(2)@N-TiO_(2)following an ambient annealing process. The diameter of a-TiO_(2)core is ~500 nm, and the thickness of NTiO_(2)branched shell is ~100 nm with gradually increased N concentration from the bottom to the edge.Ultra-thin amorphous coating layers on the branches are also observed. The morphology of the composites could be further tuned by the amount of NH_(3)·H_(2)O, and its effect on the photocatalytic performance is also investigated. The optimized a-TiO_(2)@N-TiO_(2)shows an outstanding hydrogen evolution rate of 308.1 μmol g^(-1)h^(-1)under air mass(AM) 1.5 illumination, and also exhibits highly active in photocatalytic degradation of various refractory organic pollutants, including organic dyes, phenols, antibiotics,and personal care products, with removal ratios higher than 96% after 2 h operation. This can be due to the gradient-doped N-TiO_(2)nanobranches, which not only provide bending band structure and defect level derived from the N impurities and O vacancies, resulting the formation of n-n+heterojunctions to improve the charge separation, but also enhance the charge transfer at the liquid-solid interface due to the numerous nanobranches and amorphous coating layers.展开更多
Silicon solar cells continue to dominate the market,due to the abundance of silicon and their acceptable efficiency.The heterojunction with intrinsic thin layer(HIT)structure is now the dominant technology.Increasing ...Silicon solar cells continue to dominate the market,due to the abundance of silicon and their acceptable efficiency.The heterojunction with intrinsic thin layer(HIT)structure is now the dominant technology.Increasing the efficiency of these cells could expand the development choices for HIT solar cells.We presented a detailed investigation of the emitter a-Si:H(n)lay-er of a p-type bifacial HIT solar cell in terms of characteristic parameters which include layer doping concentration,thickness,band gap width,electron affinity,hole mobility,and so on.Solar cell composition:(ZnO/nc-Si:H(n)/a-Si:H(i)/c-Si(p)/a-Si:H(i)/nc-Si:H(p)/ZnO).The results reveal optimal values for the investigated parameters,for which the highest computed efficiency is 26.45%when lighted from the top only and 21.21%when illuminated from the back only.展开更多
Coupling the effects of flexoelectricity with piezoelectricity has been proved to effectively harvest mechanical energy.In this study,a composition-graded core–shell structure(HAP@FAP)was prepared by surface-gradient...Coupling the effects of flexoelectricity with piezoelectricity has been proved to effectively harvest mechanical energy.In this study,a composition-graded core–shell structure(HAP@FAP)was prepared by surface-gradient F-doping in hydroxyapatite,which could introduce flexoelectricity by a built-in strain gradient.A flexoelectric-boosted piezoelectric response was demonstrated by piezoresponse force microscopy(PFM)characterization,showing that the piezoelectric constant of HAP@FAP was increased by 2.25 times via a lattice strain gradient induced by chemical heterogeneities derived from the unique composition-graded core-shell structure.Thus,the piezocatalytic activity of HAP@FAP for phenanthrene(PHE)degradation in soil was enhanced.This work provides a new strategy for the modification of piezoelectric catalysts for the remediation of organics-contaminated soils on industrial land.展开更多
基金This work was supported by the National Key R&D Program of China(No.2018YFB1500500)also supported by Ally Fund of Chinese Academy of Sciences(No.Y072051002).
文摘The gradient doping regions were employed in the emitter layer and the base layer of GaAs based laser power converters(LPCs).Silvaco TCAD was used to numerically simulate the linear gradient doping and exponential gradient doping structure,and analyze the transport process of photogenerated carriers.Energy band adjustment via gradient doping improved the separation and transport efficiency of photogenerated carriers and reduced the total recombination rate of GaAs LPCs.Compared with traditional structure of LPCs,the photoelectric conversion efficiency of LPCs with linear and exponential gradient doping structure were improved from 52.7%to 57.2%and 57.7%,respectively,under 808 nm laser light at the power density of 1 W/cm^(2).
基金financial support by the National Natural Science Foundation of China(NSFC,Grant No.22379153 and 22109128)the Ningbo Key Research and Development Project(2023Z147)the Ningbo 3315 Program。
文摘CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hindered by poor charge separation efficiency.Herein,we introduce a characteristic in-situ solution Fe-doping strategy that markedly improves photoelectrochemical performance of CBO,doubling the photocurrent density and achieving an unprecedented 190 mV anodic shift in the onset potential.By integrating with an electrochemical oxidation post-treatment,a record incident photon-to-current efficiency(IPCE)exceeding 40% at 0.6 V vs.RHE under visible light illumination is achieved.The versatility of the doping strategy is demonstrated across CBO photocathodes synthesized by different methods with various morphologies,grain sizes,and crystallinities.Mechanistic studies reveal that the gradient distribution of Fe^(3+)ions generates an internal electric field that facilitates efficient charge separation and increases acceptor density.The strong Fe-O bonding also enhances structural stability against photoinduced corrosion.Notably,our investigation uncovers the non-temperature-dependent nature of CBO photocurrent,indicating that PEC performance enhancement primarily depends on reducing carrier recombination rather than improving bulk conductivity.This work lays the groundwork for future advancements in water splitting performance of CBO photocathodes,offering a complementary strategy to conventional methods for enhancing charge separation efficiency.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 60678043 and 60801036)
文摘The gradient-doping structure is first applied to prepare the transmission-mode GaAs photocathode and the integral sensitivity of the sealed image tube achieves 1420μA/lm. This paper studies the inner carrier concentration distribution of the gradient-doping transmission-mode GaAs photocathode after molecular beam epitaxy （MBE） growth using the electrochemical capacitance-voltage profiling. The results show that an ideal gradient-doping structure can be obtained by using MBE growth. The total band-bending energy in the gradient-doping GaAs active-layer with doping concentration ranging from 1×10^19 cm-3 to 1×1018 cm-3 is calculated to be 46.3 meV, which helps to improve the photoexcited electrons movement toward surface for the thin epilayer. In addition,by analysis of the band offsets, it is found that the worse carrier concentration discrepancy between GaAs and GaA1As causes a lower back interface electron potential barrier which decreases the amount of high-energy photoelectrons and affects the short-wave response.
基金Project supported by the Fundamental Research Funds for the Central Universities (3203002105A2,4303002184)Jiangsu Provincial Program (JSSCRC2021491)。
文摘Ceramic fuel cells hold an important position for the sustainable energy future using renewable energy sources with high efficiency.The design and synthesis of active materials,interface engineering and having capability of low operating temperature is considered as an important factor to further increase the power output and stability of ceramic fuel cell devices.A novel methodology has vital importance to develop new functionalities of existing materials by introducing new different effects.The built-in electric field(BIEF) is one of the most recently used approaches to improve charge transfer and ionic conductivity of solid oxide materials.Herein,we demonstrate gradient doping strategy in CeO_(2)-δstructure to produce BIEF effect and to modulate the proton transport effectively at the surface layer rather than bulk structure.The inclusions of La and Sr metal ions at the surface and Co-metal ions into bulk-layer of CeO_(2)form the gradiently doped structure.The gradient doping into CeO_(2)highly improves the proton transport properties through the surface layer by modifying the energy levels.Moreover,unbalanced charge distribution due to gradient doping produces built-in electric-field to provide extra driving force for protons transport through surface layer.The acquired gradiently doped fluorite structure exhibits remarkable proton conductivity of>0.2 S/cm,as a result ceramic fuel cell shows power output of>1000 mW/cm2while operating at 500℃.This unique work highlights the critical role of gradiently doped electrolyte in electrochemical conversion energy devices and offers new understanding and practices for sustainable energy future.
基金financially supported by the National Natural Science Foundation of China(No.12304077)the Natural Science Foundation of Science and Technology Department of Sichuan Province(No.23NSFSC6224)+3 种基金Sichuan Science and Technology Program(No.2024NSFSC0989)the Key Laboratory of Computational Physics of Sichuan Province(No.YBUJSWL-YB-2022-03)the Material Corrosion and Protection Key Laboratory of Sichuan Province(No.2023CL14 and No.2023CL01)the National Innovation Practice Project(No.202411079005S).
文摘Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capacity fading.Herein,the dual-strategy of Cr,B complex coating and local gradient doping is simultaneously achieved on LLO surface by a one-step wet chemical reaction at room temperature.Density functional theory(DFT)calculations prove that stable B-O and Cr-O bonds through the local gradient doping can significantly reduce the high-energy O 2p states of interfacial lattice O,which is also effective for the near-surface lattice O,thus greatly stabilizing the LLO surface,Besides,differential electrochemical mass spectrometry(DEMS)indicates that the Cr_(x)B complex coating can adequately inhibit oxygen release and prevents the migration or dissolution of transition metal ions,including allowing speedy Li^(+)migration,The voltage and capacity fading of the modified cathode(LLO-C_(r)B)are adequately suppressed,which are benefited from the uniformly dense cathode electrolyte interface(CEI)composed of balanced organic/inorganic composition.Therefore,the specific capacity of LLO-CrB after 200 cycles at 1C is 209.3 mA h g^(-1)(with a retention rate of 95.1%).This dual-strategy through a one-step wet chemical reaction is expected to be applied in the design and development of other anionic redox cathode materials.
基金supported by the National Natural Science Foundation of China(22075170)employed resources from the BL11B station of the Shanghai Synchrotron Radiation Facility(SSRF,under contract number:2023-SSRF-PT-502681)。
文摘Increasing the charging cut-off voltage can significantly enhance the energy density of LiCoO_(2).However,the continuous deterioration of interface structure and transport kinetics under high voltage poses challenges to electrochemical stability.This work proposes to in-situ construct a uniform element gradient modification structure on the surface and subsurface of LiCoO_(2).The modification structure contains an Sb_(2)O_(3)&SbF_(x)composite coating layer and an Sb-F doped spinel-like transition layer,simultaneously.The modified sample maintains an initial discharge specific capacity of 221.2 mA h g^(-1)and a capacity retention of 86%after 200 cycles at 3–4.6 V and 0.5 C.Moreover,it has a discharge specific capacity of163.3 mA h g^(-1)at a high rate of 5 C.Meanwhile,combining highly electronegative Sb^(3+)&F^(-)that widen the Li^(+)transport channel with the amorphous coating of F^(-)doped Sb_(2)O_(3)with higher conductivity improves the interface transport kinetics.This breaks the stereotypical view in traditional concepts that fluorinated coatings or inert metal oxide coatings inhibit Li^(+)transport.Moreover,the inert composite coating combined with Sb–O–F with high bond energy stabilizes the surface structure.A series of characterizations confirm that the joint improvement of interface structure stability and transport kinetics significantly enhances the electrochemical performance of LiCoO_(2).
基金supported by the National Research Foundation of Korea(NRF)funded by the Korean government(MSIT)(NRF-2021R1A2C1095669 and NRF-2021R1F1A104936)。
文摘The construction of a homojunction is an effective approach for addressing issues such as slow charge separation and charge-transfer kinetics in photoanodes.In the present work,we designed a gradient Si-and Ti-doped Fe_(2)O_(3) homojunction photoanode to improve the photoelectrochemical(PEC)performance of a Ti-doped Fe_(2)O_(3) photoanode.Ti-FeOOH nanocorals were synthesized using a hydrothermal process,and Si-FeOOH was grown on Ti-FeOOH nanocorals using a rapid and facile microwaveassisted(MW)technique.By varying the MW irradiation time,the thickness of the Si/Ti:Fe_(2)O_(3) photoanode was adjusted and an optimized 3-Si/Ti:Fe_(2)O_(3) photoelectrode was achieved with a significantly enhanced photocurrent density(1.37 mA cm^(-2) at 1.23 V vs.RHE)and a cathodic shift of the onset potential(150 mV)compared with that of bare Ti-Fe_(2)O_(3).This enhanced PEC performance can be ascribed to homojunction formation and Si gradient doping.The Si dopant increased the donor concentration and the formation of a homojunction improved the intrinsic built-in electric field,thereby promoting charge separation and charge transfer.Furthermore,the as-formed homojunction passivated the surfacetrapping states,consequently improving the charge transfer efficiency(60%at 1.23 VRHE)at the photoanode/electrolyte interface.These findings could pave the way for the microwave-assisted fabrication of diverse efficient homojunction photoanodes for PEC water splitting applications.
基金supported by the National Natural Science Foundation of China (No. 52170083)the Excellent Youth Fund Project of Natural Science Foundation of Hunan Province (No.2021JJ20007)the Research Foundation of Education Bureau of Hunan Province,China (No. 21B0441)。
文摘A branched core-shell nanosphere composed of an anatase TiO_(2)(a-TiO_(2)) core and a TiO_(2)nanobranch shell with gradient-doped N(a-TiO_(2)@N-TiO_(2)) is synthesized by a simple in situ doping method, in which mixed crystal anatase-rutile TiO_(2)(ar-TiO_(2)) nanosphere is first prepared by oxidizing Ti using H_(2)O_(2), and then is etched by NH_(3)·H_(2)O to form(NH_(4))2TiO_(3)nanobranches, which is converted into a-TiO_(2)@N-TiO_(2)following an ambient annealing process. The diameter of a-TiO_(2)core is ~500 nm, and the thickness of NTiO_(2)branched shell is ~100 nm with gradually increased N concentration from the bottom to the edge.Ultra-thin amorphous coating layers on the branches are also observed. The morphology of the composites could be further tuned by the amount of NH_(3)·H_(2)O, and its effect on the photocatalytic performance is also investigated. The optimized a-TiO_(2)@N-TiO_(2)shows an outstanding hydrogen evolution rate of 308.1 μmol g^(-1)h^(-1)under air mass(AM) 1.5 illumination, and also exhibits highly active in photocatalytic degradation of various refractory organic pollutants, including organic dyes, phenols, antibiotics,and personal care products, with removal ratios higher than 96% after 2 h operation. This can be due to the gradient-doped N-TiO_(2)nanobranches, which not only provide bending band structure and defect level derived from the N impurities and O vacancies, resulting the formation of n-n+heterojunctions to improve the charge separation, but also enhance the charge transfer at the liquid-solid interface due to the numerous nanobranches and amorphous coating layers.
文摘Silicon solar cells continue to dominate the market,due to the abundance of silicon and their acceptable efficiency.The heterojunction with intrinsic thin layer(HIT)structure is now the dominant technology.Increasing the efficiency of these cells could expand the development choices for HIT solar cells.We presented a detailed investigation of the emitter a-Si:H(n)lay-er of a p-type bifacial HIT solar cell in terms of characteristic parameters which include layer doping concentration,thickness,band gap width,electron affinity,hole mobility,and so on.Solar cell composition:(ZnO/nc-Si:H(n)/a-Si:H(i)/c-Si(p)/a-Si:H(i)/nc-Si:H(p)/ZnO).The results reveal optimal values for the investigated parameters,for which the highest computed efficiency is 26.45%when lighted from the top only and 21.21%when illuminated from the back only.
基金the financial support provided by the National Natural Science Foundation of China(51973148 and 21938006)the National Key Technology R&D Program(2020YFC1818401)+1 种基金Basic Research Project of Leading Technology in Jiangsu Province(BK20202012)project supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Coupling the effects of flexoelectricity with piezoelectricity has been proved to effectively harvest mechanical energy.In this study,a composition-graded core–shell structure(HAP@FAP)was prepared by surface-gradient F-doping in hydroxyapatite,which could introduce flexoelectricity by a built-in strain gradient.A flexoelectric-boosted piezoelectric response was demonstrated by piezoresponse force microscopy(PFM)characterization,showing that the piezoelectric constant of HAP@FAP was increased by 2.25 times via a lattice strain gradient induced by chemical heterogeneities derived from the unique composition-graded core-shell structure.Thus,the piezocatalytic activity of HAP@FAP for phenanthrene(PHE)degradation in soil was enhanced.This work provides a new strategy for the modification of piezoelectric catalysts for the remediation of organics-contaminated soils on industrial land.
