Suppression of Sn²⁺oxidation and formation of large-size crystal grains with multifunctional chloride salt for perovskite solar cell applications

Abstract

The C6H8N2O2·2HCl additive is first doped into an FA0.75MA0.25SnI3 precursor and plays a positive role in suppressing the generation of Sn4+ and promoting the formation of large-size crystal grains in FA0.75MA0.25SnI3 perovskite films.

A Large Bandgap Organic Salt Dopant for Sn‐Based Perovskite Thin‐Film Transistor

“…This oxidation leads to self p ‐doping and the generation of Sn vacancies ( V Sn ), which is a major contributor to device performance degradation. [ 45 ] The oxidation states of Sn were quantified by scanning the Sn 3 d orbitals (Figure 3b). The proportion of Sn 4+ was dominant at 79% in pristine, but reduced to 15% for DTB 1.…”

High-efficiency and stable FA0.75MA0.25SnI3perovskite solar cells with large-size crystal grains prepared by doping with multifunctional chloride salt

“…We speculate that this is because some functional groups in the aromatic structure that do not participate in passivation –NH 3 + capture the free I − and thus reduce the formation of I 2 in the C 6 H 2 (NH 2 ) 4 ·4HCl-incorporated film. 53–58…”

“…We speculate that this is because some functional groups in the aromatic structure that do not participate in passivation -NH 3 + capture the free I À and thus reduce the formation of I 2 in the C 6 H 2 (NH 2 ) 4 Á4HCl-incorporated film. [53][54][55][56][57][58] Fig. 4 (a) UPS spectra of secondary electron cutoff and Near EF region of our pristine and 0.…”

Effects of ambient exposure on photoluminescence of Dion–Jacobson tin-based halide perovskites

“…10,11 This applies not only to ambient exposure, but even to a small amount of oxygen in the glovebox 10 or oxidizing effects of the solvent (dimethyl sulfoxide (DMSO)) used for film preparation. 12,13 Consequently, different approaches have been investigated for improving the stability of tin-based halide perovskites, such as using various additives to improve the film quality and hinder the oxidation of Sn 2+10, [14][15][16][17][18][19][20][21][22][23][24][25] and protecting the exposed surface with a protective surface layer. 11 Among various additives, tin halides and various reducing agents and/or antioxidant compounds are very common.…”

“…Among various additives, tin halides are commonly used and have yielded promising results. 10,14,15,[35][36][37] Sn(0) nanoparticles have also been effective in suppressing Sn 2+ oxidation. 38,39 While SnF 2 has been demonstrated to be very successful in suppressing the oxidation of Sn 2+ , 35,37 we have observed a strong humidity dependence of the sample stability.…”