Photo-generated carrier recombination loss at the CZTSSe/Cd S front interface is a key issue to the opencircuit voltage(V_(OC)) deficit of Cu_(2)ZnSnS_(x)Se_(4-x)(CZTSSe) solar cells. Here, by the aid of an easy-handl...Photo-generated carrier recombination loss at the CZTSSe/Cd S front interface is a key issue to the opencircuit voltage(V_(OC)) deficit of Cu_(2)ZnSnS_(x)Se_(4-x)(CZTSSe) solar cells. Here, by the aid of an easy-handling spin-coating method, a thin PCBM([6,6]-phenyl-C61-butyric acid methyl ester) layer as an electron extraction layer has been introduced on the top of CdS buffer layer to modify CZTSSe/CdS/ZnO-ITO(In_(2)O_(3):Sn) interfacial properties. Based on Sn^(4+)/DMSO(dimethyl sulfoxide) solution system, a totalarea efficiency of 12.87% with a VOC of 529 m V has been achieved. A comprehensive investigation on the influence of PCBM layer on carrier extraction, transportation and recombination processes has been carried out. It is found that the PCBM layer can smooth over the Cd S film roughness, thus beneficial for a dense and flat window layer. Furthermore, this CZTSSe/Cd S/PCBM heterostructure can accelerate carrier separation and extraction and block holes from the front interface as well, which is mainly ascribed to the downward band bending of the absorber and a widened space charge region. Our work provides a feasible way to improve the front interfacial property and the cell performance of CZTSSe solar cells by the aid of organic interfacial materials.展开更多
Comprehensive Summary Cathode interlayers(CILs)play an essential role in achieving efficient organic solar cells(OSCs).However,the electronic structure at the electrode/CIL/active layer interfaces and the underlying m...Comprehensive Summary Cathode interlayers(CILs)play an essential role in achieving efficient organic solar cells(OSCs).However,the electronic structure at the electrode/CIL/active layer interfaces and the underlying mechanisms for electron collection remain unclear,which becomes a major obstacle to develop high-performance CILs.Herein,we investigate the relationship of the electron collection abilities of four cross-linked and n-doped CILs(c-NDI:P0,c-NDI:P1,c-NDI:P2,c-NDI:P3)with their electronic structure of space charge region at heterojunction interface.By accurately calculating the depletion region width according to the barrier height,doping density and permittivity,we put forward that the optimal thickness of CIL should be consistent with the depletion region width to realize the minimum energy loss.As a result,the depletion region width is largely reduced from 13 nm to 0.8 nm at the indium tin oxide(ITO)/c-NDI:P0 interface,resulting in a decent PCE of 17.7%for the corresponding inverted OSCs.展开更多
TiO2 thin films deposited by magnetron sputtering possess excellent optical transmittance,high refractive index,good adhesion and chemical stability.In this manuscript,TiO2 thin films deposited by magnetron sputtering...TiO2 thin films deposited by magnetron sputtering possess excellent optical transmittance,high refractive index,good adhesion and chemical stability.In this manuscript,TiO2 thin films deposited by magnetron sputtering was used for the first time as an electron extraction layer in inverted polymer solar cells(IPSCs),and the effect of the TiO2 thickness on the photovoltaic performance of P3HT:PC61BM IPSCs was investigated.The highest PCE value of 3.75%was obtained when the thickness of TiO2thin films was in the range between 42 nm and 73 nm.The absorption properties,morphology and structure of the TiO2 films were characterized by UV-Vis spectroscopy,SEM and Raman spectroscopy,and were related to the device performance of P3HT:PC61BM IPSCs.The results indicate that TiO2 films deposited by magnetron sputtering are an excellent electron extraction layer for IPSCs.展开更多
Plasmon-induced hot energy in metal nanostructures holds great promise for photocatalytic organic conversions.However,maintaining the high-energy state of hot electrons within these structures remains challenging,even...Plasmon-induced hot energy in metal nanostructures holds great promise for photocatalytic organic conversions.However,maintaining the high-energy state of hot electrons within these structures remains challenging,even in hybrid metal-semiconductor heterojunctions.The rapid relaxation of hot electrons(<1 ps)due to a thick-shell and loosely bound semiconductor layer limits their extraction efficiency and utilization effectiveness during photocatalysis.Herein,we fabricated a novel metalsemiconductor heterojunction(P2-Au)with ultrathin-shell semiconductor layer by combing ultra-small metal chalcogenide semiconductor clusters(P2)with gold nanorods(Au NRs),which exhibits high-efficiency extraction of hot electrons and photocatalytic application.The robust binding of P2 cluster,with its smaller volume and larger energy level splitting compared to large-sized quantum dots,not only significantly increases the yield of hot electrons but also enables their rapid extraction and sustains long-lived(>2 ns)high-energy states.As a proof of concept,the composite photocatalyst achieves near-infrared-lightdriven C(sp^(3))-S cross-coupling reactions for the first time.This protocol effectively produces over 50 alkylthioethers from a wide scope range of non-active alkyl bromides and chlorides,aryl and alkyl thiols.This work provides a new strategy for highefficiency extraction of hot electrons within plasmonic metal nanostructures and paves the way for hot electron-driven photocatalytic organic transformations.展开更多
In this study,numerical simulation and discharge current tests were conducted on an inductively coupled radio frequency(RF)plasma cathode.Numerical simulations and experimental measurements were performed to study the...In this study,numerical simulation and discharge current tests were conducted on an inductively coupled radio frequency(RF)plasma cathode.Numerical simulations and experimental measurements were performed to study the factors influencing the electron extraction characteristics,including the gas type,gas flow,input power and extracting voltage.The simulation results were approximately consistent with the experimental results.We experimentally found that the RF input power mainly determines the extracted electron current.An electron current greater than 1 A was acquired at 270 W(RF input power),2.766 sccm(xenon gas).Our results prove that an inductively coupled RF plasma cathode can be reasonable and feasible,particularly for low power electric propulsion devices.展开更多
Both of planar and mesoporous architectures prevail for perovskite solar cells(PSCs).However,it is still an open question how the architecture affects the performance of PSCs.The inconsistent results in the references...Both of planar and mesoporous architectures prevail for perovskite solar cells(PSCs).However,it is still an open question how the architecture affects the performance of PSCs.The inconsistent results in the references often create confusion.In particular,the specific roles of mesoporous frameworks are yet to be well elaborated and require further clarification.In this study,we carefully compared the properties of perovskite films and the device performances for both architectures to unravel the roles of mesoporous TiO2 framworks in CH3NH3PbI3 PSCs.The detailed characterizations of structural,microscopic,optical and electrical properties revealed that the presence of mesoporous TiO2 framework contributed to enlarged perovskite crystal sizes,enhanced light harvesting,efficient electron extration and suppressed charge recombination.As a result,compared with the planar device,the mesoporous device yielded an improved power conversion efficiency of 18.18%,coupled with a reduced hystersis.This study reveals the benefits of mesoporous TiO2 framework in PSCs and provides the guidance for the design and optimization of architectures for high-performance devices.展开更多
The perovskite layer,electron transport layer(ETL)and their interface are closely associated with carrier transport and extraction,which possess a pronounced effect on current density.Consequently,the dissatisfactory ...The perovskite layer,electron transport layer(ETL)and their interface are closely associated with carrier transport and extraction,which possess a pronounced effect on current density.Consequently,the dissatisfactory electric properties of functional layers pose a serious challenge for maximizing the thermodynamic potential of current density of perovskite solar cells(PSCs).Herein,we report an ion diffusion-induced double layer doping strategy for efficient and stable PSCs,where LiOH is directly added into SnO_(2)colloidal dispersion solution.It is uncovered that a small amount of Li+ions remain in the ETL and doped SnO2 while a large amount of Li+ions diffuse to SnO_(2)/perovskite interface and into perovskite layer and gradient concentration distribution is spontaneously formed.The Li+ion doping endows both perovskite and SnO_(2)layers improved electric properties,which contributes to facilitated carrier transport and extraction.Moreover,the crystallinity and grain size of perovskite films are enhanced after doping.The doped device delivers a higher power conversion efficiency(PCE)of 21.31%together with improved ambient stability in comparison with the control device(PCE=19.26%).This work demonstrates a simple and effective ion diffusion-induced double layer by chemical doping strategy to advance the development of perovskite photovoltaics.展开更多
基金supported by the National Natural Science Foundation of China(U2002216,52172261,51627803,51972332,22075150,and U1902218)the National Key Research and Development Program of China(2019YFE0118100)。
文摘Photo-generated carrier recombination loss at the CZTSSe/Cd S front interface is a key issue to the opencircuit voltage(V_(OC)) deficit of Cu_(2)ZnSnS_(x)Se_(4-x)(CZTSSe) solar cells. Here, by the aid of an easy-handling spin-coating method, a thin PCBM([6,6]-phenyl-C61-butyric acid methyl ester) layer as an electron extraction layer has been introduced on the top of CdS buffer layer to modify CZTSSe/CdS/ZnO-ITO(In_(2)O_(3):Sn) interfacial properties. Based on Sn^(4+)/DMSO(dimethyl sulfoxide) solution system, a totalarea efficiency of 12.87% with a VOC of 529 m V has been achieved. A comprehensive investigation on the influence of PCBM layer on carrier extraction, transportation and recombination processes has been carried out. It is found that the PCBM layer can smooth over the Cd S film roughness, thus beneficial for a dense and flat window layer. Furthermore, this CZTSSe/Cd S/PCBM heterostructure can accelerate carrier separation and extraction and block holes from the front interface as well, which is mainly ascribed to the downward band bending of the absorber and a widened space charge region. Our work provides a feasible way to improve the front interfacial property and the cell performance of CZTSSe solar cells by the aid of organic interfacial materials.
基金financial support from Guangdong Major Project of Basic and Applied Basic Research(No.2019B030302007)Bureau of International Cooperation Chinese Academy of Sciences(121111KYSB20200043)+1 种基金National Natural Science Foundation of China(NSFC,21835006,51961135103)B.X.would like to acknowledge the financial support from Fundamental Research Funds for the Central Universities(buctrc202140).
文摘Comprehensive Summary Cathode interlayers(CILs)play an essential role in achieving efficient organic solar cells(OSCs).However,the electronic structure at the electrode/CIL/active layer interfaces and the underlying mechanisms for electron collection remain unclear,which becomes a major obstacle to develop high-performance CILs.Herein,we investigate the relationship of the electron collection abilities of four cross-linked and n-doped CILs(c-NDI:P0,c-NDI:P1,c-NDI:P2,c-NDI:P3)with their electronic structure of space charge region at heterojunction interface.By accurately calculating the depletion region width according to the barrier height,doping density and permittivity,we put forward that the optimal thickness of CIL should be consistent with the depletion region width to realize the minimum energy loss.As a result,the depletion region width is largely reduced from 13 nm to 0.8 nm at the indium tin oxide(ITO)/c-NDI:P0 interface,resulting in a decent PCE of 17.7%for the corresponding inverted OSCs.
基金financially supported the National Natural Science Foundation of China (20904057 21074055)+3 种基金the Open Fund of Key Laboratory of Advanced Functional Polymeric Materials of College of Hunan Province (12K049)Beijing Natural Science Foundation (2122050)Basic Research Foundation of the Central Universities (2013JBZ004)J. Zhang acknowledges support by the "100 Talents Program" of the Chinese Academy of Sciences
文摘TiO2 thin films deposited by magnetron sputtering possess excellent optical transmittance,high refractive index,good adhesion and chemical stability.In this manuscript,TiO2 thin films deposited by magnetron sputtering was used for the first time as an electron extraction layer in inverted polymer solar cells(IPSCs),and the effect of the TiO2 thickness on the photovoltaic performance of P3HT:PC61BM IPSCs was investigated.The highest PCE value of 3.75%was obtained when the thickness of TiO2thin films was in the range between 42 nm and 73 nm.The absorption properties,morphology and structure of the TiO2 films were characterized by UV-Vis spectroscopy,SEM and Raman spectroscopy,and were related to the device performance of P3HT:PC61BM IPSCs.The results indicate that TiO2 films deposited by magnetron sputtering are an excellent electron extraction layer for IPSCs.
基金supported by the National Natural Science Foundation of China(U22A20432,92261205,22071165,22201103)the 111 Project(D20015)+2 种基金the Guangzhou Municipal Science and Technology Bureau(2024A04J3490)supported by the State Key Laboratory of Bioactive Molecules and Druggability Assessment(202402025)the Fundamental Research Funds for the Central Universities。
文摘Plasmon-induced hot energy in metal nanostructures holds great promise for photocatalytic organic conversions.However,maintaining the high-energy state of hot electrons within these structures remains challenging,even in hybrid metal-semiconductor heterojunctions.The rapid relaxation of hot electrons(<1 ps)due to a thick-shell and loosely bound semiconductor layer limits their extraction efficiency and utilization effectiveness during photocatalysis.Herein,we fabricated a novel metalsemiconductor heterojunction(P2-Au)with ultrathin-shell semiconductor layer by combing ultra-small metal chalcogenide semiconductor clusters(P2)with gold nanorods(Au NRs),which exhibits high-efficiency extraction of hot electrons and photocatalytic application.The robust binding of P2 cluster,with its smaller volume and larger energy level splitting compared to large-sized quantum dots,not only significantly increases the yield of hot electrons but also enables their rapid extraction and sustains long-lived(>2 ns)high-energy states.As a proof of concept,the composite photocatalyst achieves near-infrared-lightdriven C(sp^(3))-S cross-coupling reactions for the first time.This protocol effectively produces over 50 alkylthioethers from a wide scope range of non-active alkyl bromides and chlorides,aryl and alkyl thiols.This work provides a new strategy for highefficiency extraction of hot electrons within plasmonic metal nanostructures and paves the way for hot electron-driven photocatalytic organic transformations.
基金supported by Joint Fund for Equipment Preresearch and Aerospace Science and Technology(No.6141B061203)。
文摘In this study,numerical simulation and discharge current tests were conducted on an inductively coupled radio frequency(RF)plasma cathode.Numerical simulations and experimental measurements were performed to study the factors influencing the electron extraction characteristics,including the gas type,gas flow,input power and extracting voltage.The simulation results were approximately consistent with the experimental results.We experimentally found that the RF input power mainly determines the extracted electron current.An electron current greater than 1 A was acquired at 270 W(RF input power),2.766 sccm(xenon gas).Our results prove that an inductively coupled RF plasma cathode can be reasonable and feasible,particularly for low power electric propulsion devices.
基金financially supported by the National Natural Science Foundation of China(51602088)the Open Fund of the Key Laboratory of Photovoltaic and Energy Conservation Materials,Chinese Academy of Sciences(PECL2019KF007)and China Postdoctoral Science Foundation(2017T100313)。
文摘Both of planar and mesoporous architectures prevail for perovskite solar cells(PSCs).However,it is still an open question how the architecture affects the performance of PSCs.The inconsistent results in the references often create confusion.In particular,the specific roles of mesoporous frameworks are yet to be well elaborated and require further clarification.In this study,we carefully compared the properties of perovskite films and the device performances for both architectures to unravel the roles of mesoporous TiO2 framworks in CH3NH3PbI3 PSCs.The detailed characterizations of structural,microscopic,optical and electrical properties revealed that the presence of mesoporous TiO2 framework contributed to enlarged perovskite crystal sizes,enhanced light harvesting,efficient electron extration and suppressed charge recombination.As a result,compared with the planar device,the mesoporous device yielded an improved power conversion efficiency of 18.18%,coupled with a reduced hystersis.This study reveals the benefits of mesoporous TiO2 framework in PSCs and provides the guidance for the design and optimization of architectures for high-performance devices.
基金supported by the Defense Industrial Technology Development Program(No.JCKY2017110C0654)the National Natural Science Foundation of China(Nos.11974063 and 61904023)。
文摘The perovskite layer,electron transport layer(ETL)and their interface are closely associated with carrier transport and extraction,which possess a pronounced effect on current density.Consequently,the dissatisfactory electric properties of functional layers pose a serious challenge for maximizing the thermodynamic potential of current density of perovskite solar cells(PSCs).Herein,we report an ion diffusion-induced double layer doping strategy for efficient and stable PSCs,where LiOH is directly added into SnO_(2)colloidal dispersion solution.It is uncovered that a small amount of Li+ions remain in the ETL and doped SnO2 while a large amount of Li+ions diffuse to SnO_(2)/perovskite interface and into perovskite layer and gradient concentration distribution is spontaneously formed.The Li+ion doping endows both perovskite and SnO_(2)layers improved electric properties,which contributes to facilitated carrier transport and extraction.Moreover,the crystallinity and grain size of perovskite films are enhanced after doping.The doped device delivers a higher power conversion efficiency(PCE)of 21.31%together with improved ambient stability in comparison with the control device(PCE=19.26%).This work demonstrates a simple and effective ion diffusion-induced double layer by chemical doping strategy to advance the development of perovskite photovoltaics.
