Suppression of Non-radiative Recombination with Efficient Doping of Spiro-OMeTAD for High-Performance Perovskite Solar Cells

Metal-halide perovskite solar cells(PSCs)have attracted considerable attention during the past decade.However,due to the existence of non-radiative recombination losses,the best power conversion efficiency(PCE)is still lower than the theoret-ical limit defined by Shockley-Queser theory.In this work,we investigate l,2,3-oxathiazin-4(3h)-one,6-methyl-2,2-dioxide(acesulfame potassium,abbreviated as AK)as a additional dopant for the 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenyl-amine)-9,9'-spirobifluorene(Spiro-OMeTAD)and fabricate PSCs in the air.It is found that 12 mol％fraction of AK relative to lithium bis((trifluoromethyl)sulfonyl)-amide(Li-TFSI)reduces the non-radiative recombination from 86.05％to 69.23％,resulting in an average 0.08 V of Voc enhancement.The champion solar cell gives a perovskite solar cells up to 21.9％and over 84％retention of the initial value during 720 h aging in dry air with 20％-30％humidity.