Instant p-doping and pore elimination of the spiro-OMeTAD hole-transport layer in perovskite solar cells.

An instant p-doping strategy employing 4-tert-butyl-2-chloropyridine and tert-butyl peroxybenzoate for the spiro-OMeTAD hole-transport layer (HTL) in perovskite solar cells (PSCs) is proposed to replace the conventional 4-tert-butylpyridine-doped HTL. The novel doping process eliminates the formation of pores in the HTL. Meanwhile, a 21.4% efficiency is achieved on the corresponding absolute methylammonium-free PSCs with significantly improved thermal and moisture stability.

Selective grain boundary passivation by ammonium nitrate for enhanced performance and stability of FA-Cs based perovskite solar cells.

Grain boundaries of metal halide perovskites contain massive defects that are detrimental to photovoltaics applications. This work demonstrates that inorganic NH4NO3 can selectively passivate the grain boundaries of perovskite films and improve their moisture resistance simultaneously, resulting in enhanced performance and stability of the methylammonium-free perovskite solar cells.