The advantages of OPV （organic photovoltaic） are low cost, little pollution and flexible. But challenge for OPV manufacture still is lacking of accurately performance measurement due to capacitance issue. Firstly, c...The advantages of OPV （organic photovoltaic） are low cost, little pollution and flexible. But challenge for OPV manufacture still is lacking of accurately performance measurement due to capacitance issue. Firstly, characterization of OPV requires considering the slowly temporal response due to capacitance effect, and the relative I-V （current-voltage） curves are strongly dependent on the voltage sweep direction, even for the sweep time only in few seconds or less. Secondly, the IPCE （incident photon-to-electron conversion efficiency） also shows the slowly temporal response due to capacitance effect and is dependent on the wavelength of the incident light. Furthermore, the related features for measuring I-V curves are more sensitive with temperature due to non-linear characteristics issue, but current IPCE spectra of OPV are similar to that happened in conventional crystalline Si or amorphous silicon devices. In this work, we developed a RTOSM （real-time one-sweep method） applied both in I-V and IPCE to analysis different electronic transport materials, and result showed this new approach proposed a good way to slow down testing time and having better accuracy for OPV measurement by eliminating acceptance effect instantly.展开更多
The hole and electron mobilities of the amorphous films of the organic semiconductor 4,4′-N,N′-dicarbazole-biphenyl (CBP) at different electric fields were measured through the time of flight (TOF) method. Based on ...The hole and electron mobilities of the amorphous films of the organic semiconductor 4,4′-N,N′-dicarbazole-biphenyl (CBP) at different electric fields were measured through the time of flight (TOF) method. Based on its crystalline structure, the hole and electron mobilities of CBP were calculated. A detailed comparison between experimental and theoretical results is necessary for further understanding its charge transport properties. In order to do this, charge mobilities at zero electric field, μ(0), were deduced from experimental data as a link between experimental and theoretical data. It was found that the electron transport of CBP is less affected by traps compared with its hole transport. This unusual phenomenon can be understood through the distributions of frontier molecular orbitals. We showed that designing materials with frontier molecular orbitals localized at the center of the molecule has the potency to reduce the influence of traps on charge transport and provide new insights into designing high mobility charge transport materials.展开更多
Perovskite solar cells(PSCs)commonly exhibit significant performance degradation due to ion migration through the top charge transport layer and ultimately metal electrode corrosion.Here,we demonstrate an interfacial ...Perovskite solar cells(PSCs)commonly exhibit significant performance degradation due to ion migration through the top charge transport layer and ultimately metal electrode corrosion.Here,we demonstrate an interfacial management strategy using a boron chloride subphthalocyanine(Cl_(6)SubPc)/fullerene electron-transport layer,which not only passivates the interfacial defects in the perovskite,but also suppresses halide diffusion as evidenced by multiple techniques,including visual element mapping by electron energy loss spectroscopy.As a result,we obtain inverted PSCs with an efficiency of 22.0%(21.3%certified),shelf life of 7000 h,T_(80) of 816 h under damp heat stress(compared to less than 20 h without Cl_(6)SubPc),and initial performance retention of 98%after 2000 h at 80℃in inert environment,90%after 2034 h of illumination and maximum power point tracking in ambient for encapsulated devices and 95%after 1272 h outdoor testing ISOS-O-1.Our strategy and results pave a new way to move PSCs forward to their potential commercialization solidly.展开更多
文摘The advantages of OPV （organic photovoltaic） are low cost, little pollution and flexible. But challenge for OPV manufacture still is lacking of accurately performance measurement due to capacitance issue. Firstly, characterization of OPV requires considering the slowly temporal response due to capacitance effect, and the relative I-V （current-voltage） curves are strongly dependent on the voltage sweep direction, even for the sweep time only in few seconds or less. Secondly, the IPCE （incident photon-to-electron conversion efficiency） also shows the slowly temporal response due to capacitance effect and is dependent on the wavelength of the incident light. Furthermore, the related features for measuring I-V curves are more sensitive with temperature due to non-linear characteristics issue, but current IPCE spectra of OPV are similar to that happened in conventional crystalline Si or amorphous silicon devices. In this work, we developed a RTOSM （real-time one-sweep method） applied both in I-V and IPCE to analysis different electronic transport materials, and result showed this new approach proposed a good way to slow down testing time and having better accuracy for OPV measurement by eliminating acceptance effect instantly.
基金supported by the National Key Basic Research and Development Program of China (2009CB623604)the National Natural Science Foundation of China (50990060, 51073809 and 21161160447)
文摘The hole and electron mobilities of the amorphous films of the organic semiconductor 4,4′-N,N′-dicarbazole-biphenyl (CBP) at different electric fields were measured through the time of flight (TOF) method. Based on its crystalline structure, the hole and electron mobilities of CBP were calculated. A detailed comparison between experimental and theoretical results is necessary for further understanding its charge transport properties. In order to do this, charge mobilities at zero electric field, μ(0), were deduced from experimental data as a link between experimental and theoretical data. It was found that the electron transport of CBP is less affected by traps compared with its hole transport. This unusual phenomenon can be understood through the distributions of frontier molecular orbitals. We showed that designing materials with frontier molecular orbitals localized at the center of the molecule has the potency to reduce the influence of traps on charge transport and provide new insights into designing high mobility charge transport materials.
基金supported by the National Natural Science Foundation of China (61775091, and U2001216)the Shenzhen Key Laboratory Project (ZDSYS201602261933302)+2 种基金Natural Science Foundation of Shenzhen Innovation Committee (JCYJ20180504165851864)the support of Research Grants Council Collaborative Research Fund (RGC- CRF) grant C5037-18GSeed Funding for Strategic Interdisciplinary Research Scheme of the University of Hong Kong and Shenzhen Science and Technology Commission Projects (JCYJ20170818141216288)
文摘Perovskite solar cells(PSCs)commonly exhibit significant performance degradation due to ion migration through the top charge transport layer and ultimately metal electrode corrosion.Here,we demonstrate an interfacial management strategy using a boron chloride subphthalocyanine(Cl_(6)SubPc)/fullerene electron-transport layer,which not only passivates the interfacial defects in the perovskite,but also suppresses halide diffusion as evidenced by multiple techniques,including visual element mapping by electron energy loss spectroscopy.As a result,we obtain inverted PSCs with an efficiency of 22.0%(21.3%certified),shelf life of 7000 h,T_(80) of 816 h under damp heat stress(compared to less than 20 h without Cl_(6)SubPc),and initial performance retention of 98%after 2000 h at 80℃in inert environment,90%after 2034 h of illumination and maximum power point tracking in ambient for encapsulated devices and 95%after 1272 h outdoor testing ISOS-O-1.Our strategy and results pave a new way to move PSCs forward to their potential commercialization solidly.
