Synthesis, structure and orange-light emission of a zero-dimensional antimony(III) halide with the 4,4'-(ethane-1,2-diyl)dipyridin-1-ium cation.

Exploring orange-light-emitting lead-free halides with high photoluminescence quantum yields (PLQYs) is a significant challenge in luminescent materials research. Herein, a zero-dimensional organic-inorganic hybrid halide, namely, 4,4'-(ethane-1,2-diyl)dipyridin-1-ium pentachloridoantimonate(III), (C12H14N2)[SbCl5] or [H2bpa][SbCl5], where bpa is 1,2-bis(pyridin-4-yl)ethane, was synthesized via acid solution evaporation. The compound crystallizes in the triclinic space group P1. The asymmetric unit consists of an [SbCl5]2- anion and two half [H2bpa]2+ cations. The [SbCl5]2- anion and [H2bpa]2+ cations are linked via intermolecular hydrogen bonds and π-π interactions to form a three-dimensional supramolecular architecture. Significantly, this halide exhibits highly efficient orange-light emission centred at 600 nm, with a PLQY of 65.57%.