Enhanced Blue Emission via Pressure Treatment of an Organic-Inorganic Zinc Bromide†

Abstract

Pressure-treatment has been shown to be an effective means to enhance fluorescence of organic-inorganic halides though it is only limited to few examples. Here, we report the pressure-dependent structural evolution and emission enhancement upon compression treatment of a zero-dimensional halide, BTPP₂ZnBr₄ (BTPP = Benzyl triphenyl phosphonium). Compared to the uncompressed BTPP₂ZnBr₄ crystal, the pressure-treated sample shows a maximum 7-fold intensified fluorescence at ambient conditions while maintaining the wide-spectrum blue emission feature. This significantly boosted emission is attributed to the pressure-induced irreversible structural distortion which effectively reduces the non-radiative recombination. This work demonstrates the promising potential of pressure treatment in achieving bright organic-inorganic halide emitters and other molecular fluorescent materials.