The Aggregation-induced Emission Materials And Non-fullerene Acceptor Materials For Organic Solar Cells: Design, Synthesis, Performance Research And Application

In this paper, we have designed and synthesized a series of organic photoelectric functional materials, the main work is divided into the following two parts:In the first part, we designed and synthesized a series of new aggregation-induced emission materials, where the vinyl moiety severs as the core, thiophene and triphenylamine sever as the rotor. We introduced different amounts of triphenylamine by the modification on the thiophene part to get DT2 A, DT3 A and DT4 A, in which emit yellow or orange fluorescence. Because of the different structure and symmetry, three compounds showed the different features. With the good symmetry and excellent crystalline, DT2 A formed microrods by self-assembly and showed good optical waveguide property. Due to the large molecular structure, DT4 A showed twist and loose crystalline state. The fluorescence emission spectrum of DT4 A obviously redshift with an external force effect, in which demonstrating a property of reversible piezfluorochromic fluorescence. We also used DT2 A and DT4 A to detect nitro compounds and DT2 A showed better sensitivity than that of DT4 A.In the second part, we synthesized small molecule non-fullerene acceptor for organic solar cells TrPDI, in which truxene with rigid structure as the core and N,N’-bis-(1-ethylhexyl)-perylene-3,4,9,10-tetracarboxylic diimide(PDI) unit as the terminal groups, forming a three-dimensional structure. After combination with PTB7-Th as the donor, the obtained BHJ-OSC devices exhibited PCE of 1.71%, with a high open circuit voltage(Voc) of 0.80 V, short circuit current density(Jsc) of 4.64 mA cm-2 and FF of 0.44 without using any additives. To further study the effect of planarity for the acceptor based on truxene, we synthesized a novel acceptor TrThDC based on truxene as a central building block, 1,1-dicyanomethylene-3-indanone(DC) as electron-withdrawing end groups and thiophene as ?-bridges. The solution processed BHJ OSCs based on PTB7-Th: TrThDC showed a PCE of 1.13%. The strategy of connecting PDI into the rigid and twist structure can improve the solubility and prevent from stronger aggregation of PDI, and thus preferable to improve the energy conversion efficiency of organic solar cells.