Effect of low-concentration Rb+ mixing on semiconductor majority charge carriers type of perovskite light-absorption layer by using two-step spin-coating method

Abstract

In recent years, perovskite materials have been the subject of great progress in optoelectronic devices. The perovskite layer is the light absorption layer of perovskite solar cells (PSCs), and the majority charge carriers type play a crucial role in the formation of a P-N junction. In this paper, the light absorption layer of PSCs was Rb-mixed at a low concentrations by using a two-step spin-coating method, which could adjust the majority charge carriers type in perovskite films from N-type to P-type, and it has little influence on the crystal structure and light absorption capacity of perovskite. In addition, low concentration Rb-mixing is dierent from high concentration Rb-mixing. With increasing Rb-mixing concentration, the perovskite grains does not change shape. Although the quality of perovskite films deteriorated and the PL peaks exhibit a slight blue shift after mixing, the efficiency only slightly decreased, indicating that the new P-N hetero-junction was still formed after mixing, which provided a new idea for the future research of homo-junction PSCs.