Water-Molecule-Induced Emission Transformation of Zero-Dimension Antimony-Based Metal Halide

Low-dimensional organic-inorganic metal halides have recently emerged as a class of promising luminescent materials. However, the intrinsic toxicity of lead would strongly hamper future application. Herein, we synthesized a new type of lead-free zero-dimensional (OD) antimony-based organic-inorganic metal halide single crystals, (PPZ)(2)SbCl7 center dot 5H(2)O (PPZ = 1-phenylpiperazine), which features a broadband emission at 720 nm. Ultrafast transient absorption and temperature-dependent photoluminescence (PL) spectra are combined to investigate the PL mechanism, revealing that self-trapped exciton recombination was involved. Furthermore, it is interesting that (PPZ)(2)SbCl7 center dot 5H(2)O material shows reversible PL emission transformation between red light (720 nm) and yellow light (590 nm) as water molecules are inserted or removed from the lattice. Such reversible emission transformation phenomenon renders the (PPZ)(2) SbCl7 center dot 5H(2)O as a potential low-cost water sensing material.

Automated summary

Researchers synthesized a new type of lead-free organic-inorganic metal halide material with broadband emission and reversible emission transformation, making it a potential water sensing material.