Synthetic-Method-Dependent Antimony Bromides and Their Photoluminescent Properties.

Recently, excellent optical properties of low-dimensional organic-inorganic metal halides, stemming from their tunable structure and optoelectronic properties, have been demonstrated. The synthetic method is critical because it is highly related to the structure and properties of the halide. Herein, we obtain two different antimony bromides, (Bmpip) 2 SbBr 5 and (Bmpip) 3 Sb 2 Br 9 , which both possess the P 2 1 / c space group having different crystal structures, and this confirms the important influence of synthesis on the single-crystal structure. (Bmpip) 2 SbBr 5 contains Bmpip + and [SbBr 5 ] 2- pyramids, and (Bmpip) 3 Sb 2 Br 9 consists of Bmpip + and Sb-based dimers [Sb 2 Br 9 ] 3- . Under 400 nm excitation, (Bmpip) 2 SbBr 5 exhibits a 640 nm orange emission with a quantum yield of ∼11.5% owing to Sb 5s 2 electron luminescence. A diode was fabricated by (Bmpip) 2 SbBr 5 and commercial phosphors and showed a high color render index of 92. Our work reveals the effect of the preparation method on the crystal structure. A luminescent material was finally identified.