The efficient production of ammonia by reducing nitrates at room temperature and ambient pressure is a promising alternative to the Haber-Bosch process and can effectively overcome the attendant water pollution issues...The efficient production of ammonia by reducing nitrates at room temperature and ambient pressure is a promising alternative to the Haber-Bosch process and can effectively overcome the attendant water pollution issues.Herein,a new idea has been realized for rational and selective construction of the sp-carbon-metal-carbon interface,comprised of electronic-donating triple bonds in graphdiyne and electron-withdrawing iron carbides,for a highly efficient nitrate reduction reaction.The as-prepared sp-carbon-metal-carbon interfacial structures greatly increase the charge transfer ability and electrical conductivity of the system.The proposed concept of incomplete charge transfer has demonstrated significantly high selectivity,activity,and stability in catalytic system.The catalyst exhibits high Faradaic efficiency of over>95%and a NH3 yield rate up to 205.5μmolNH_(3) cm^(-2) h^(-1) in dilute nitrate conditions without any contaminant.展开更多
Remarkable progress in high-performance polymer solar cells demonstrates their great potential for practical applications in the near future. Indeed, the power conversion efficiencies over 10% have been reported by ma...Remarkable progress in high-performance polymer solar cells demonstrates their great potential for practical applications in the near future. Indeed, the power conversion efficiencies over 10% have been reported by many research groups, which are achieved through rational optimization of light-harvesting materials, interfaces and device processing technologies. In this mini review, we summarized the recent progress of highly efficient polymer solar cells, with specifically concern on successful strategies of rational molecular design of electron-donating and electron-accepting materials, elaborative interfacial engineering, and reasonable device architectures.展开更多
This article presents our experimental studies to unravel the dynamic photovoltaic processes occurring at donor:acceptor(D:A)and electrode:active layer(E:A)interfaces under device-operating conditions by using two uni...This article presents our experimental studies to unravel the dynamic photovoltaic processes occurring at donor:acceptor(D:A)and electrode:active layer(E:A)interfaces under device-operating conditions by using two unique magneto-optical measurements,namely photo-induced capacitance and magnetic field effect measurement.First,we have found that a higher surface polarization of dielectric thin film can decrease the surface charge accumulation at E:A interface.The photo-induced capacitance results indicate that dielectric thin film plays a crucial role in the charge collection in generating photocurrent in organic solar cells.Second,our experimental results from magnetic field effect show that the binding energies of charge transfer(CT)states at D:A interface can be evaluated by using the critical bias required to completely dissociate the CT states.This is the first experimental demonstration that the binding energies of CT states can be measured under deviceoperating conditions.Furthermore,we use our measurement of magnetic field effect to investigate the most popular organic photovoltaic solar cells,organometal halide perovskite photovoltaic devices.The results of magneto-photoluminescence show that the photogenerated electrons and holes are inevitably recombined into electron–hole pairs through a spin-dependent process in the perovskites.Therefore,using spin polarizations can present a new design to control the photovoltaic loss in perovskites-based photovoltaic devices.Also,we found that introducing D:A interface can largely affect the bulk charge dissociation and recombination in perovskite solar cells.This indicates that the interfacial and bulk photovoltaic processes are internally coupled in developing photovoltaic actions in perovskite devices.Clearly,these magneto-optical measurements show a great potential to unravel the deeper photovoltaic processes occurring at D:A and E:A interfaces in both organic bulk-heterojunction and perovskite solar cells under device-operating conditions.展开更多
In this work,we have systematically investigated the post-thermal annealing-induced enhancement in photovoltaic performance of a 2,4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl]squaraine(DIBSQ)/C60 planar heteroju...In this work,we have systematically investigated the post-thermal annealing-induced enhancement in photovoltaic performance of a 2,4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl]squaraine(DIBSQ)/C60 planar heterojunction(PHJ)organic solar cells(OSCs).An increased power conversion efficiency(PCE)of 3.28%has been realized from a DIBSQ/C60 device with thermal annealing at 100°C for 4 min,which is about 33%enhancement compared with that of the as-cast device.The improvement of the device performance may be mainly ascribed to the crystallinity of the DIBSQ film with post-thermal annealing,which will change the DIBSQ donor and C60 acceptor interface from^PHJ to hybrid planar-mixed heterojunction.This new donor-acceptor heterojunction structure will significantly improve the charge separation and charge collection efficiency,as well as the open circuit voltage(Voc)of the device,leading to an enhanced PCE.This work provides an effective strategy to improve the photovoltaic performance of SQ-based OSCs.展开更多
基金This research was made possible as a result of a generous grant from the National Natural Science Foundation of China(grant nos.21790050,21790051,and 22021002)the National Key Research and Development Project of China(grant no.2018YFA0703501)the Key Program of the Chinese Academy of Sciences(grant no.XDPB13).
文摘The efficient production of ammonia by reducing nitrates at room temperature and ambient pressure is a promising alternative to the Haber-Bosch process and can effectively overcome the attendant water pollution issues.Herein,a new idea has been realized for rational and selective construction of the sp-carbon-metal-carbon interface,comprised of electronic-donating triple bonds in graphdiyne and electron-withdrawing iron carbides,for a highly efficient nitrate reduction reaction.The as-prepared sp-carbon-metal-carbon interfacial structures greatly increase the charge transfer ability and electrical conductivity of the system.The proposed concept of incomplete charge transfer has demonstrated significantly high selectivity,activity,and stability in catalytic system.The catalyst exhibits high Faradaic efficiency of over>95%and a NH3 yield rate up to 205.5μmolNH_(3) cm^(-2) h^(-1) in dilute nitrate conditions without any contaminant.
基金supported by the Ministry of Science and Technology(2014CB643501)the National Natural Science Foundation of China(21520102006,21634004,51673069,21490573)the Guangdong Natural Science Foundation(S2012030006232)
文摘Remarkable progress in high-performance polymer solar cells demonstrates their great potential for practical applications in the near future. Indeed, the power conversion efficiencies over 10% have been reported by many research groups, which are achieved through rational optimization of light-harvesting materials, interfaces and device processing technologies. In this mini review, we summarized the recent progress of highly efficient polymer solar cells, with specifically concern on successful strategies of rational molecular design of electron-donating and electron-accepting materials, elaborative interfacial engineering, and reasonable device architectures.
基金supported by the National Science Foundation of the United States(ECCS-1102011,ECCS-0644945,and CBET-1438181)the support from Sustainable Energy Education and Research Center and Center for Materials Processing at the University of Tennessee+1 种基金This research was partially conducted at the Center for Nanophase Materials Sciences based on user project(CNMS2012-106,CNMS2012-107,CNMS-2012-108),which is sponsored at Oak Ridge National Laboratory by the Division of Scientific User Facilities,U.S.Department of Energythe University of Tennessee also acknowledge the project support from the National Natural Science Foundation of China(21161160445,61077020)
文摘This article presents our experimental studies to unravel the dynamic photovoltaic processes occurring at donor:acceptor(D:A)and electrode:active layer(E:A)interfaces under device-operating conditions by using two unique magneto-optical measurements,namely photo-induced capacitance and magnetic field effect measurement.First,we have found that a higher surface polarization of dielectric thin film can decrease the surface charge accumulation at E:A interface.The photo-induced capacitance results indicate that dielectric thin film plays a crucial role in the charge collection in generating photocurrent in organic solar cells.Second,our experimental results from magnetic field effect show that the binding energies of charge transfer(CT)states at D:A interface can be evaluated by using the critical bias required to completely dissociate the CT states.This is the first experimental demonstration that the binding energies of CT states can be measured under deviceoperating conditions.Furthermore,we use our measurement of magnetic field effect to investigate the most popular organic photovoltaic solar cells,organometal halide perovskite photovoltaic devices.The results of magneto-photoluminescence show that the photogenerated electrons and holes are inevitably recombined into electron–hole pairs through a spin-dependent process in the perovskites.Therefore,using spin polarizations can present a new design to control the photovoltaic loss in perovskites-based photovoltaic devices.Also,we found that introducing D:A interface can largely affect the bulk charge dissociation and recombination in perovskite solar cells.This indicates that the interfacial and bulk photovoltaic processes are internally coupled in developing photovoltaic actions in perovskite devices.Clearly,these magneto-optical measurements show a great potential to unravel the deeper photovoltaic processes occurring at D:A and E:A interfaces in both organic bulk-heterojunction and perovskite solar cells under device-operating conditions.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.61604093)the Natural Science Foundation of Shanghai(Grant Nos.16ZR1411000 and 18ZR1413800)the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20180978).
文摘In this work,we have systematically investigated the post-thermal annealing-induced enhancement in photovoltaic performance of a 2,4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl]squaraine(DIBSQ)/C60 planar heterojunction(PHJ)organic solar cells(OSCs).An increased power conversion efficiency(PCE)of 3.28%has been realized from a DIBSQ/C60 device with thermal annealing at 100°C for 4 min,which is about 33%enhancement compared with that of the as-cast device.The improvement of the device performance may be mainly ascribed to the crystallinity of the DIBSQ film with post-thermal annealing,which will change the DIBSQ donor and C60 acceptor interface from^PHJ to hybrid planar-mixed heterojunction.This new donor-acceptor heterojunction structure will significantly improve the charge separation and charge collection efficiency,as well as the open circuit voltage(Voc)of the device,leading to an enhanced PCE.This work provides an effective strategy to improve the photovoltaic performance of SQ-based OSCs.
