Polymer electron acceptors are the key materials in all-polymer solar cells(all-PSCs).In this review,we focused on introducing the principle of boron-nitrogen coordination bond(B←N),and summarizing our recent researc...Polymer electron acceptors are the key materials in all-polymer solar cells(all-PSCs).In this review,we focused on introducing the principle of boron-nitrogen coordination bond(B←N),and summarizing our recent research on polymer electron acceptors containing B←N unit for efficient all-PSC devices.Two approaches have been reported to design polymer electron acceptors using B←N unit.One is to replace a C-C unit by a B←N unit in conjugated polymers to transform a polymer electron donor to a polymer electron acceptor.The other approach is to construct novel electron-deficient building block based on B←N unit for polymer electron acceptors.The polymer electron acceptors containing B←N unit showed tunable lowest unoccupied molecular orbital(LUMO) energy levels and exhibited excellent all-PSC device performance with power conversion efficiency of exceeding6%.These results indicate that organic boron chemistry is a new toolbox to develop functional polymer materials for optoelectronic device applications.展开更多
Organic small molecules （TPA-BT3T, TPA-PT3T, and TPA-DFBT3T） using triphenylamine as a donor unit, terthiophene as a bridge, and benzo-2,1,3-thiadiazole （BT）, [1,2,5]thiadiazolo[3,4-e]pyridine （PT） or 5,6-difluo...Organic small molecules （TPA-BT3T, TPA-PT3T, and TPA-DFBT3T） using triphenylamine as a donor unit, terthiophene as a bridge, and benzo-2,1,3-thiadiazole （BT）, [1,2,5]thiadiazolo[3,4-e]pyridine （PT） or 5,6-difluorobenzo[c][1,2,5]thiadiazole （DFBT） as an acceptor unit were designed and synthesized through Suzuki coupling reactions. These molecules exhibited good thermal stability with decomposition temperatures over 380℃ and broad absorption from 300 to 700 nm. Photovoltaic devices were fabricated with these small molecules as donors and PC71BM as an acceptor. The TPA-BT3T based devices exhibited a power conversion efficiency of 2.89%, higher than those of the TPA-PT3T- and TPA-DFBT3T-based devices （1.34% and 1.54% respectively）. The effects of electron-withdrawing units on absorption, energy level, charge transport, morphology, and photovoltaic properties also were investigated.展开更多
Four new 2D donor–acceptor conjugated polymers were designed and synthesized.These new polymers comprised fluorenealt-triphenylamine or carbazole-alt-triphenylamine as the backbones,and pendants with 2,1,3-benzothiad...Four new 2D donor–acceptor conjugated polymers were designed and synthesized.These new polymers comprised fluorenealt-triphenylamine or carbazole-alt-triphenylamine as the backbones,and pendants with 2,1,3-benzothiadiazole(BT)or naphtho[1,2-c:5,6-c]bis[1,2,5]thiadiazole(NT)in a triphenylamine unit as the side groups.By changing the acceptor BT for a stronger electron-withdrawing unit of NT moiety in the side chain,the energy levels,absorption spectra,band gaps,and charge-transport abilities of the resultant polymers could be effectively tuned.Bulk heterojunction solar cells with these polymers as the electron donors and(6,6)-phenyl-C71-butyric acid methyl ester as the electron acceptor exhibited high open-circuit voltage(more than 0.8 e V).The power conversion efficiency can be improved from 1.37%to 3.52%by replacing the BT with an NT moiety,which indicates that introducing NT as the side-chain building block can be an effective strategy to construct efficient 2D conjugated polymers for PSCs.展开更多
基金supported by the National Key Basic Research and Development Program of China(2014CB643504,2015CB655001)the National Natural Science Foundation of China(51373165,21625403,21574129,21404099)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB12010200)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2017265)
文摘Polymer electron acceptors are the key materials in all-polymer solar cells(all-PSCs).In this review,we focused on introducing the principle of boron-nitrogen coordination bond(B←N),and summarizing our recent research on polymer electron acceptors containing B←N unit for efficient all-PSC devices.Two approaches have been reported to design polymer electron acceptors using B←N unit.One is to replace a C-C unit by a B←N unit in conjugated polymers to transform a polymer electron donor to a polymer electron acceptor.The other approach is to construct novel electron-deficient building block based on B←N unit for polymer electron acceptors.The polymer electron acceptors containing B←N unit showed tunable lowest unoccupied molecular orbital(LUMO) energy levels and exhibited excellent all-PSC device performance with power conversion efficiency of exceeding6%.These results indicate that organic boron chemistry is a new toolbox to develop functional polymer materials for optoelectronic device applications.
基金supported by the National Natural Science Foundation of China(21025418,51261130582)the National Basic Research Program of China(2011CB808401)the Chinese Academy of Sciences
文摘Organic small molecules （TPA-BT3T, TPA-PT3T, and TPA-DFBT3T） using triphenylamine as a donor unit, terthiophene as a bridge, and benzo-2,1,3-thiadiazole （BT）, [1,2,5]thiadiazolo[3,4-e]pyridine （PT） or 5,6-difluorobenzo[c][1,2,5]thiadiazole （DFBT） as an acceptor unit were designed and synthesized through Suzuki coupling reactions. These molecules exhibited good thermal stability with decomposition temperatures over 380℃ and broad absorption from 300 to 700 nm. Photovoltaic devices were fabricated with these small molecules as donors and PC71BM as an acceptor. The TPA-BT3T based devices exhibited a power conversion efficiency of 2.89%, higher than those of the TPA-PT3T- and TPA-DFBT3T-based devices （1.34% and 1.54% respectively）. The effects of electron-withdrawing units on absorption, energy level, charge transport, morphology, and photovoltaic properties also were investigated.
基金financially supported by the National Basic Research Program of China(2014CB643501)the National Natural Science Foundation of China(21125419 and 51361165301)+1 种基金the Guangdong Natural Science Foundation(S2012030006232)the Research Fund for the Doctoral Program of Higher Education of China(20120172140001)
文摘Four new 2D donor–acceptor conjugated polymers were designed and synthesized.These new polymers comprised fluorenealt-triphenylamine or carbazole-alt-triphenylamine as the backbones,and pendants with 2,1,3-benzothiadiazole(BT)or naphtho[1,2-c:5,6-c]bis[1,2,5]thiadiazole(NT)in a triphenylamine unit as the side groups.By changing the acceptor BT for a stronger electron-withdrawing unit of NT moiety in the side chain,the energy levels,absorption spectra,band gaps,and charge-transport abilities of the resultant polymers could be effectively tuned.Bulk heterojunction solar cells with these polymers as the electron donors and(6,6)-phenyl-C71-butyric acid methyl ester as the electron acceptor exhibited high open-circuit voltage(more than 0.8 e V).The power conversion efficiency can be improved from 1.37%to 3.52%by replacing the BT with an NT moiety,which indicates that introducing NT as the side-chain building block can be an effective strategy to construct efficient 2D conjugated polymers for PSCs.
