p-Thiocresol Functionalized Cesium Lead Bromide (PTC@CsPbBr3): A Fluorometric Sensing Probe for the Detection of Cholesterol.

Inorganic halide-based perovskites (e.g., cesium lead bromide) are tremendously useful semiconducting materials due to their unique optoelectronic properties. However, degradation of these perovskites under humid conditions is one of the major drawbacks to prevent their wide applications. Herein, passivated cesium lead bromide nanoparticles are synthesized using p-thiocresol as a passivating ligand, and this stable version of perovskite is later applied successfully as a sensor probe towards cholesterol detection. The designed sensor can detect cholesterol with a lower detection limit of 0.24 ppm and a fast response time of 10 s. The mechanism of quenching PTC@CsPbBr3 upon the gradual addition of cholesterol is discussed. Further, the sensor is successfully applied in the detection of cholesterol in real samples (blood serum). This work presents PTC@CsPbBr3 as a novel sensing platform for detecting cholesterol well in biomedical applications.

CsPbBr3 perovskites: A dual fluorescence sensor to distinguish ethanol from methanol.

In recent years, lead halide perovskites have emerged as a promising material with defect tolerance, thermally stable, and optoelectronic properties. However, the instability is the major factor which hinder their potential applications in various fields. This work demonstrates the chemical stability of Cesium Lead Bromide (CsPbBr3) under different passivation condition with an objective to develop alcohol sensor. Cetyltrimethyl ammonium bromide (CTAB) passivated CsPbBr3 demonstrated as a turn off fluorescent probe for alcohols and more significantly turn on fluorescent probe for ethanol. Herein, it is shown that CTAB passivated CsPbBr3 can effectively discriminate ethanol from methanol owing to its different mode of interaction with ethanol and methanol. The outstanding optical properties of halide perovskites with an ultra-low detection limit of 7.3 ppb was obtained for ethanol detection. The sensing performance of the material is also validated with petrol and cough syrup samples showing excellent performance for future implementation with practical applications.