Natively textured surface of Ga-doped ZnO films electron transporting layer for perovskite solar cells: further performance analysis from device simulation

摘要

In this work, the natively textured surface of gallium-doped zinc oxide (GZO) films were obtained onto quartz substrates by radio frequency magnetron sputtering. The optimal optoelectronic properties of GZO thin film exhibited the lowest resistivity 6.8x10(-4)cm, where the carrier concentration and carrier mobility were 5.3x10(20)cm(-3) and 17.3cm(2)V(-1)s(-1), respectively, and the transmittance above 87% in the range of 0.4-1.2 mu m. Meanwhile, this GZO thin film had a low surface work function of 3.9eV. We used a two-steps spin-coating method to deposit the perovskite films. The optical band gap of this perovskite films is 1.561eV. The planar perovskite solar cells device modeling based on GZO electron transporting layer was performed by the Solar Cell Capacitance Simulator program. We inputted the electrical and optical parameters of GZO thin film in our perovskite solar cells simulation model. With the increasing of carrier concentration, a high-power conversion efficiency of 20.167% was obtained. Modifying GZO surface, obtaining a suitable surface work function (3.9eV), it could reduce the interlayer contact barrier and optimize the energy level matching. At the perovskite/electron transporting layer interface, no electron barrier was formed, which facilitated electron extraction and reduced interface recombination. The higher power conversion efficiency of 21.132% was obtained.