Organic-Inorganic Hybrid Tin Halide Single Crystals with Sulfhydryl and Hydroxyl Groups: Formation, Optical Properties, and Stability

Lead ( Pb)-free halide hybrid materials have received a great deal of attention because of their potential in optoelectronic applications. However, heteroatom-based amine lead-free tin halide hybrid single crystals have not been well investigated yet. Detailed synthetic processes, growth, crystal structures, and stability of (ACH(2)CH(2)NH(3))(2)SnBr6 (A = OH or SH) and (BCH2CH2NH3)(2)SnI4 (B = I or SH) single crystals were investigated. Interestingly, (IH3NCH2CH2SSCH2CH2NH3)(2)HPO3 exhibited orange-red photoluminescence (PL) at about 620 nm with an average PL life time of about 912 ns. (HSCH2CH2NH3)(2)SnI4 single crystals exhibited a PL peak at 620 nm with an average PL lifetime of about 0.607 ns. More importantly, (HSCH2CH2NH3)(2)SnI4 single crystals exhibited reversible red-black color transformations when exposed to a H3PO2 solution and an ambient atmosphere, which was attributed to oxidation from Sn2+ to Sn4+, rather than from I- to I-3(-) (I-2). The intriguing characteristics should provide guidance for further optoelectronic applications of these Pb-free halide hybrid materials.

Automated summary

Lead-free tin halide hybrid single crystals have been investigated in terms of their synthetic processes, crystal structures, and stability. Interesting optical properties such as photoluminescence and color transformations were observed. These findings provide valuable guidance for the further development of lead-free halide hybrid materials in optoelectronic applications.