Blue light emissive zero-dimensional hybrid cadmium bromide as fluorescence sensor toward benzaldehyde

Organic-inorganic hybrid low-dimensional metal halides have been widely studied as a new class of luminescence materials due to abundant structural diversity and intriguing photophysical property. Herein, we explored two new Cd-based 0D halides of [BHEPZ]CdBr4 (BHEPZ = 1,4-Bis(2-hydroxyethyl) piperazine) and [EPIPZ]CdBr4 (EPIPZ = 1-ethylpiperazine) through facile wet-chemistry method. These 0D halides exhibit blue light emissions derived from radiative recombination of self-trapped excitons (STEs) based on detailed spectroscopy investigations. More interestingly, [BHEPZ]CdBr4 exhibits rapid luminescence off switching toward benzaldehyde but fails in any other organic solvents. In-depth investigations demonstrate that the detection limit can fall to 2.65 ppm indicating perfect real-time fluorescent probe to detect benzaldehyde with high sensitivity and selectivity. This work enriches the cadmium halide materials and provide a new perspective for potential applications of 0D hybrid metal halides.