Wide-bandgap perovskites for multijunction solar cells: improvement of crystalline quality of Cs0.1FA0.9PbI1.4Br1.6 by using lead thiocyanate

High quality wide bandgap perovskite acting as top cells in multijunction solar cells were developed by adding Pb(SCN) 2 to precursor solutions. The number of grain boundaries was reduced and passivated leading to an increase in carrier extraction.