Reducing energy loss(V_(loss))is one of the most crucial challenges in organic photovoltaic cells.The V_(loss),determined by the differences between the optical band gap(E_(g))of the active layer material and the open...Reducing energy loss(V_(loss))is one of the most crucial challenges in organic photovoltaic cells.The V_(loss),determined by the differences between the optical band gap(E_(g))of the active layer material and the open-circuit voltage(V_(oc))of the device,is generally alleviated by lowering the energy difference between the lowest unoccupied molecular orbital(LUMO)and highest occupied molecular orbital(HOMO)level of the donor(D)and acceptor(A).In this work,we synthesized two A-π-D-π-A-type small-molecule donors(SMDs)SM-benzotriazole(BTz)-1 and SM-BTz-2 by introducing a BTzπ-bridge unit and terminal regulation.The BTzπ-bridge unit significantly lowers the HOMO energy level of SMDs,resulting in high V_(oc)and high mobility,achieving a balance of low energy loss(<0.5 eV)and high efficiency.Ultimately,the organic solar cells based on SM-BTz-2 as the donor and Y6 as the acceptor obtain a high V_(oc)of 0.91 V,J_(sc) of 22.8 mA cm^(−2),fill factor of 68%,and power conversion efficiency(PCE)of 14.12%,which is one of the highest efficiencies based on the SMDs with triazoleπ-bridges to date.What’s more,the BTzπ-bridge unit is a potential unit that can improve mobility and reduce energy loss.展开更多
Organic photovoltaic cells(OPVs) have attracted more and more attention due to its highly potential application to solve the energy crisis considering its advantages,such as low cost and ease of large area production....Organic photovoltaic cells(OPVs) have attracted more and more attention due to its highly potential application to solve the energy crisis considering its advantages,such as low cost and ease of large area production.The power conversion efficiency(PCE) of OPVs has undergone a more than nine-fold increase from ～1.0% by Tang in 1986 to 9.2% in 2010 announced by Mitsubishi Chemical.The major challenges of obtaining high efficiency OPVs are the synthesis of new narrow band gap materials,controlling molecular arrangement,designing novel configuration cells for better photon harvesting in the active layer.In the article,we summarized the recent progress of novel narrow band gap photovoltaic materials and the effective methods to control the morphology of donor and acceptor in the blend films for high performance of OPVs.展开更多
Organic film photovoltaic (PV) cell, ITO/NPB/Y(ACA) 3phen/Mg∶Ag, was fabricated. The NPB, N,N′ bis (1 naphthyl) N,N′ diphenyl 1,1′ biphenyl 4,4′ diamine, and Y(ACA) 3phen, (tris (acetylacetonato) (mono phenothrol...Organic film photovoltaic (PV) cell, ITO/NPB/Y(ACA) 3phen/Mg∶Ag, was fabricated. The NPB, N,N′ bis (1 naphthyl) N,N′ diphenyl 1,1′ biphenyl 4,4′ diamine, and Y(ACA) 3phen, (tris (acetylacetonato) (mono phenothroline) yttrium, are the electron acceptor and donor in the PV cell, respectively. Under UV light with 4 mW·cm -2 , the cell show short circuit current of 46 μA·cm -2 , open circuit voltage of 2.18 V, fill factor of 0.30, and the overall power conversion efficiency of 0.7%, respectively. The responding region is matched to the adsorption of NPB film. It is found that the PV cell indicates electroluminescent (EL) performances and could emit blue light at dc voltage. The maximum luminance is about 750 cd·m -2 at 15 V.展开更多
The reliable information about interface energetics of organic materials, especially the energy level alignment at organic heterostructures is of pronounced importance for unraveling the photon harvesting and charge s...The reliable information about interface energetics of organic materials, especially the energy level alignment at organic heterostructures is of pronounced importance for unraveling the photon harvesting and charge separation process in organic photovoltaic(OPV) cells. This article provides an overview of interface energetics at typical planar and mixed donor-acceptor heterostructures, perovskite/organic hybrid interfaces, and their contact interfaces with charge collection layers. The substrate effect on energy level offsets at organic heterostructures and the processes that control and limit the OPV operation are presented. Recent efforts on interface engineering with electrical doping are also discussed.展开更多
基金the National Key Research and Development Program of China(2019YFA0705900)the National Natural Science Foundation of China(51820105003,21734008,61904181,52173188 and 52103243)+1 种基金the Key Research Program of the Chinese Academy of Sciences(XDPB13)the Basic and Applied Basic Research Major Program of Guangdong Province(2019B030302007).
文摘Reducing energy loss(V_(loss))is one of the most crucial challenges in organic photovoltaic cells.The V_(loss),determined by the differences between the optical band gap(E_(g))of the active layer material and the open-circuit voltage(V_(oc))of the device,is generally alleviated by lowering the energy difference between the lowest unoccupied molecular orbital(LUMO)and highest occupied molecular orbital(HOMO)level of the donor(D)and acceptor(A).In this work,we synthesized two A-π-D-π-A-type small-molecule donors(SMDs)SM-benzotriazole(BTz)-1 and SM-BTz-2 by introducing a BTzπ-bridge unit and terminal regulation.The BTzπ-bridge unit significantly lowers the HOMO energy level of SMDs,resulting in high V_(oc)and high mobility,achieving a balance of low energy loss(<0.5 eV)and high efficiency.Ultimately,the organic solar cells based on SM-BTz-2 as the donor and Y6 as the acceptor obtain a high V_(oc)of 0.91 V,J_(sc) of 22.8 mA cm^(−2),fill factor of 68%,and power conversion efficiency(PCE)of 14.12%,which is one of the highest efficiencies based on the SMDs with triazoleπ-bridges to date.What’s more,the BTzπ-bridge unit is a potential unit that can improve mobility and reduce energy loss.
基金supported by the National Natural Science Foundation of China (10804006,20904057 and 21074055)the Natural Science Foundation of Beijing (2122050)+1 种基金the Basic Research Foundation of the Central Universities (2011JBM123)F. Zhang thanks the support from the "Double Hundred Talents Plan" of Beijing Jiaotong University and the State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences
文摘Organic photovoltaic cells(OPVs) have attracted more and more attention due to its highly potential application to solve the energy crisis considering its advantages,such as low cost and ease of large area production.The power conversion efficiency(PCE) of OPVs has undergone a more than nine-fold increase from ～1.0% by Tang in 1986 to 9.2% in 2010 announced by Mitsubishi Chemical.The major challenges of obtaining high efficiency OPVs are the synthesis of new narrow band gap materials,controlling molecular arrangement,designing novel configuration cells for better photon harvesting in the active layer.In the article,we summarized the recent progress of novel narrow band gap photovoltaic materials and the effective methods to control the morphology of donor and acceptor in the blend films for high performance of OPVs.
文摘Organic film photovoltaic (PV) cell, ITO/NPB/Y(ACA) 3phen/Mg∶Ag, was fabricated. The NPB, N,N′ bis (1 naphthyl) N,N′ diphenyl 1,1′ biphenyl 4,4′ diamine, and Y(ACA) 3phen, (tris (acetylacetonato) (mono phenothroline) yttrium, are the electron acceptor and donor in the PV cell, respectively. Under UV light with 4 mW·cm -2 , the cell show short circuit current of 46 μA·cm -2 , open circuit voltage of 2.18 V, fill factor of 0.30, and the overall power conversion efficiency of 0.7%, respectively. The responding region is matched to the adsorption of NPB film. It is found that the PV cell indicates electroluminescent (EL) performances and could emit blue light at dc voltage. The maximum luminance is about 750 cd·m -2 at 15 V.
基金supported by the National Basic Research Program of China (2014CB932600)the National Natural Science Foundation of China (91433116, 11474214)+2 种基金Jiangsu Science and Technology Department (BK20140053)Bureau of Science and Technology of Suzhou Municipality (SYG201525, ZXG201422)the project of the Priority Academic Program Development (PAPD) of Jiangsu Higher Education Institutions
文摘The reliable information about interface energetics of organic materials, especially the energy level alignment at organic heterostructures is of pronounced importance for unraveling the photon harvesting and charge separation process in organic photovoltaic(OPV) cells. This article provides an overview of interface energetics at typical planar and mixed donor-acceptor heterostructures, perovskite/organic hybrid interfaces, and their contact interfaces with charge collection layers. The substrate effect on energy level offsets at organic heterostructures and the processes that control and limit the OPV operation are presented. Recent efforts on interface engineering with electrical doping are also discussed.
