Photovoltaic Performance Research Of Quinoxaline-Based Donor/Acceptor For Ternary Organic Solar Cells

With the over-exploitation and utilization of fossil energy and the increasingly serious problem of environmental pollution,the development of environment-friendly renewable energy is urgent.Organic solar cells（OSCs）have attracted more and more researchers’attention due to their advantages of light weight,low cost,wide source,flexibility,and simple fabrication process.In recent years,in addition to the development of new high-efficiency photovoltaic donor/acceptor materials,the process of preparing ternary organic photovoltaics devices by adding a third component materials is also considered an effective method to improve the photoelectric conversion efficiency.The researchers blended materials with complementary energy levels and complementary absorption in the same active layer to improve the photoelectric conversion efficiency（PCE）of the device.This paper optimizes the device by introducing the third component material.The main research work is as follows:1)In the binary organic photovoltaic active layer based on PBDTTS-2FCl Qx:Y6,Adding PC₇₁BM as the third component prepared efficient ternary OSCs.The study found that the introduction of the highly crystalline PC₇₁BM effectively adjusted the crystallinity of the blend,supplemented and broadened the absorption spectrum of the active layer,and provided more transport channels for the charge transfer of the device and greatly improve the stability of the device.When the content of PC₇₁BM is 10 wt%,the ternary device based on PBDTTS-2FCl Qx:Y6:PC₇₁BM obtains an excellent efficiency of 13.59%,which is significantly higher than the binary device efficiency（12.41%）based on PBDTTS-2FCl Qx:Y6.2)In the organic photovoltaic active layer based on J71:IT-4F,the symmetric quinoxaline-type polymer donor material PBDTTS-2FQx was added as the third component material to prepare efficient ternary OSCs.The results show that combining two compatible donor materials into an"alloy donor material"improves the exciton dissociation,charge transport and charge collection efficiency of the device.The ternary device component J71:PBDTTS-2FQx:IT-4F achieved a device efficiency of 11.23%,which was significantly higher than the binary device component efficiency（9.52%）with J71:IT-4F as the active layer.3)In the organic photovoltaic active layer based on PM6:Y6,a quinoxaline-type small molecule acceptor material（DFTQA-2FIC）was selected as the third component material to prepare efficient ternary OSCs.The results showed that adding suitable acceptor materials as the third component in binary organic photovoltaic devices is beneficial to promote the dissociation and transfer of excitons at the interface.The constructed PM6:Y6:DFTQA-2FIC ternary device component achieves a device efficiency of up to 17.29%,which is significantly higher than that of the binary device component with PM6:Y6 as the active layer（16.09%）.