Numerical simulation of electron-transport-layer-free CH3NH3Pb(I1-xBrx)3 perovskite solar cells

Numerical simulation can provide an effective theoretical basis for studying carrier transport, collection and diffusion in perovskite solar cells. We used SCAPS-1D software to perform numerical simulations based on CH3NH3Pb(I1-xBrx)(3) solar cells. First, we analyzed the thickness of the absorbing layer, doping concentration and defect density, and found that the thickness of 0.5 mu m and the defect density of 3 x 10(11) cm(-3) have great photoelectric conversion performance. We then adjusted the thickness and doping concentration of the hole transport layer to further optimize the P3HT hole transport and diffusion performance. In addition, we found that the interface defect layer has little effect on device performance, but the FTO layer plays an important role in the electron-free layer structure of transmitting electrons. Finally, we compared the electron-transport-layer-free structure with the traditional electron transport layer structure containing PC61BM, SnO2, TiO2 and C-60, and predicted the excellent photoelectric conversion performance of the electron-transport-layer-free solar cell structure by 26.15%. Our work simplifies the preparation process of traditional solar cells, providing new insights not only for the development of high-efficiency solar cells, but also for the development of solar cells without electron transport layers.