Designing Zero-Dimensional Cadmium-Based Organic–Inorganic Hybrids: The Role of Halogen Doping in Modulating Multifunctional Properties

Advances in materials science are increasingly dependent on the development of multifunctional materials capable of improving system efficiency and reducing the environmental impact. In this study, two zero-dimensional (0D) cadmium-based organic-inorganic hybrid materials (BEMPD)₂CdBr₄ (BEMPD-Br, <b>1</b>) and (BEMPD)₂CdBr₂Cl₂ (BEMPD-ClBr, <b>2</b>) (BEMPD = 1-(2-bromoethyl)-1-methylpiperidine) were prepared by halogen doping. Compound <b>2</b> is a mixed halide in which there are two halogen sites, Cl and Br, and in a disordered state, which has a regulatory effect on the structural distortion and properties of the compound. The Curie temperatures of compounds <b>1</b> and <b>2</b> are 348 and 390 K, respectively, and the UV-vis absorption spectra showed that the direct band gaps of compounds <b>1</b> and <b>2</b> were 4.68 and 4.8 eV, respectively. In addition, room-temperature photoluminescence experiments show broadband emission peaks at 717 and 683 nm for compounds <b>1</b> and <b>2</b>, respectively, with fluorescence lifetimes of 2.414 and 3.915 μs. These 0D hybrids provide an avenue for the development of smart materials and optoelectronic devices, and also provide positive clues for manipulating the properties of organic-inorganic hybrid compounds.