Presentation Information
[7p-S201-12]Universal, Stoichiometrically-Neutral Pseudo-Halide Additives for Suppressed Halide Segregation in Wide Bandgap Perovskite Solar Cells
〇(D)Aly Aly1, Richard Murdey1, Wan Linbo1, Minh Anh Truong1, Tomoya Nakamura1, Atsushi Wakamiya1 (1.Kyoto University)
Keywords:
Perovskite Solar Cells,Wide bandgap,Pseudo-halides
Wide bandgap perovskites suffers from halide segregation, a phenomenon wherein the iodine and the bromide ions segregate into two different domains, which may negatively impact the long-term stability of the solar cells. Lead thiocyanate, Pb(SCN)2, when added to perovskite precursor solutions, can improve the performance and stability of the resulting solar cells. However, Pb(SCN)2 increases the concentration of Pb2+ in the precursor solution. The resulting perturbation of the ABX3 stoichiometry can lead to reduced crystallinity and increased defect density.
Therefore, we explore ammonium thiocyanate (NH4SCN), which supplies SCN- while leaving the A and B site cation balance intact. In our evaluation, NH4SCN-treated wide-bandgap devices showed superior performance to other thiocyanate additives and superior operational stability compared to the control, maintaining a ~40 meV higher Voc over 100 h of maximum-power-point tracking under 1 sun.
Therefore, we explore ammonium thiocyanate (NH4SCN), which supplies SCN- while leaving the A and B site cation balance intact. In our evaluation, NH4SCN-treated wide-bandgap devices showed superior performance to other thiocyanate additives and superior operational stability compared to the control, maintaining a ~40 meV higher Voc over 100 h of maximum-power-point tracking under 1 sun.