Large-scale synthesis of cesium lead halide perovskite nanocrystals for zinc ion detection

Quantum dots of halide perovskite are considered to be the promising candidates for optoelectronic applications. Although many methods have been developed to prepare CsPbX3 (X = Cl, Br, I) nanocrystals, the large-scale synthesis of CsPbX3 nanocrystals remains an outstanding challenge. In this paper, nanocrystals of CsPbBr3 were subjected to one-pot synthesis in octane by using a precursor with a high concentration. CsPbBr3 nanocrystals were obtained in octane dispersion as well as in the precipitation. All obtained nanocrystals were in the CsPbBr3 nanocubes with uniform morphologies and average size of 7.8 nm, and featured the same emission peak and photoluminescence quantum yield (PLQY), which indicated that the concentration of the precursor did not influence the nucleation of the CsPbBr3 nanocrystals. This result implied a large-scale synthesis of the nanocrystals. Following this, similar to 1 g of CsPbBr3 nanocrystals were obtained only in the 10-mL octane solution when the concentration of PbBr2 was up to 0.3 mol/L. This one-pot process was suitable for the large-scale and cost-effective synthesis of CsPbX3 nanocrystals. Besides, the obtained CsPbBr3 nanocrystals were used as probes of the [Zn2+] detection for the first time. It was found that the Zn2+ ions could quench the photoluminescence intensity of CsPbX3 nanocrystals and the quench effect showed high selectivity and high anti-interference.