Stability Analysis of Lead-Free Perovskite Solar Cells by Cation Doping

Abstract

The emerging lead-Free perovskite has attracted enormous attention due to its eco-friendly nature Among the lead-free perovskites tin-based perovskite has lots of excellent optoelectronic properties such as appropriate band gap of 1 41 eV high absorption coefficient (105 cm-1) long carrier length (500 nm) and so on However the easy oxidation of Sn2+ to Sn4+ in tin-based perovskite will create vancancy which alter the electronic properties of tin-based perovskite As a result the oxidation reaction is a key issue for stabilizing the tin-based perovskite and the device performance In this study we codope HAI and EDAI2 in FASnI3 perovskite to stabilize the perovskite film as well as device stability The device performance is optimized at a precursor ration HAI:FAI=3:97 with a doping level of 10% EDAI2 to attain a power conversion efficiency (PCE) of 5 17% The device works stably on different temperature at 80?C 100?C and 120?C for 12hr in a globe box Additionally the device without encapsulation displayed can survive for 9 hr in air Doping cation in tin-based perovskite paves the way for stable tin-based perovskite solar cells The new material is doped in lead-free perovskite to help promotion of the efficiency and stability

Date of Award	2019
Original language	English
Supervisor	Chao-Yu Chen (Supervisor)