Effect of Phenethylammonium Thiocyanate Additive in Tin Perovskite for Efficient and Stable Pb-free Perovskite Solar Cells

The phenethylammonium thiocyanate (PEASCN) was introduced into the FASnI
3
perovskite film as a pseudohalide functional additive. This results in the suppression of Sn-oxidation and compact and larger grain film with better crystallinity. The device with PEASCN additive improved the power conversion efficiency (PCE) from 4.52% (control) to 9.65% (PEASCN). The device analysis revealed that the PEASCN additive has improved the optoelectronic properties coupled with a higher diffusion potential and passivation of defect densities in the Sn-PSCs. This report suggests that the pseudohalide-based functional additive is propitious for film growth, modification of surface chemistry, and defects at interface and bulk.