Boosting the stability of indoor perovskite solar cells by the rational selection of electron transport layers

This study investigates a series of electron transport materials (ETMs) in wide-bandgap perovskite solar cells with the Cs0.17FA0.83Pb(I0.6Br0.4)3 photoactive layer. Power conversion efficiencies of up to 23.2% were achieved under an artificial light source (1000 lux, 6000 K LED) for the devices incorporating SnO2 passivated with fullerene derivative. However, the fullerene derivative induced rapid interfacial degradation. In contrast, solar cells utilizing SnO2 ETM passivated with amino-based compounds exhibited stable performance under continuous 1 Sun illumination during 2300 h in an inert atmosphere and under indoor lighting in ambient conditions. This was attributed to a reduced density of defects on the surface of the ETM and enhanced interfacial stability. These findings underscore the importance of the rational ETM selection for efficient and stable wide-bandgap perovskites.