Study Of Ternary Organic Solar Cells Based On Thermally Activated Delayed Fluorescence

Ternary Organic solar cells have recently attracted increasing attention due to the unique advantages such as the simple manufacturing process,diverse material selection and low cost.In scientific research,Thermally Activated Delayed Fluorescence?TADF?is a common material for producing Organic light-emitting diodes?OLED?.It is not used in industrialized OLED products because of its broad emission spectrum.This paper innovatively doped the TADF material which is commonly used in OLED as the third component into the binary heterojunction P3HT:PC₇₁BM system to study the influence of different doping concentrations on the ternary organic solar cells.The specific work is as follows;?1?We study the ternary solar cells by doping a TADF material,2CzPN,in the P3HT:PC₇₁BM blends,and testing the photovoltaic performance,absorption performance,surface morphology and carrier mobility.Given the complementary absorption with P3HT,2CzPN was doped into(P3HT:PC₇₁BM)-based binary blends to developed ternary OSCs.The ternary OSCs with 3.0 wt%of 2CzPN displayed the small aggregation phases of film morphology and higher hole-electron mobility,which are significantly beneficial for efficient charge generation and collection.Thus leading to an impressive efficiency of 3.76%which results in a 31%enhancement of power conversion efficiency?PCE?compared with the conventional binary device.?2?Another TADF material,4CzIPN,was selected as the third component.The ternary organic solar cells with different doping ratios were also prepared and their properties were characterized.The test results show that the performance of the device is optimal when the doping ratio is 1 wt%.And the optimal photoelectric conversion efficiency is 3.94%,which is an increase of 38.7%compared with the standard device of binary solar cells.The main reason for the performance improvement is that in addition to the energy transfer between 4CzIPN and P3HT,by testing the morphology of different doping ratios,we found that due to the?-?stacking effect between the 4CzIPN molecules,a more flat film was formed.The morphology of the active layer with the doping ratio of0 wt%,0.5 wt%,1.0 wt%,and 2.0 wt%was tested.The root mean square roughness was reduced from 3.8 nm to 0.75 nm,which greatly optimizes the morphology of the active layer.In summary,to use TADF materials 2CzPN and 4CzIPN as the third component of the P3HT:PC₇₁BM system with low concentration effectively enhances the performance of organic solar cells.This work provides an effective solution for the realization of new ternary organic solar cells.