Probing the Structural Degradation of CsPbBr Perovskite Nanocrystals in the Presence of HO and HS: How Weak Interactions and HSAB Matter.

Structural degradation of all inorganic CsPbBr in the presence of moisture is considered as one of its major limitations to use as an active component in various light-harvesting and light-emitting devices. Herein, we used two similar molecules, HO and HS, with similar structures, to follow the decomposition mechanism of CsPbBr perovskite nanocrystals. Interestingly, HO acts as a catalyst for the decomposition of CsPbBr, which is in contrast to HS.

Simple and Cost-Effective Quantum Dot Chemodosimeter for Visual Detection of Biothiols in Human Blood Serum.

An emission "turn-off" chemodosimeter for the naked-eye detection of biothiols using silica-overcoated cadmium selenide quantum dots is developed. Hole scavenging by the thiol group of cysteine, homocysteine, or glutathione on interaction with quantum dots resulted in an instant and permanent emission quenching under physiologically relevant conditions. Also, the emission suppression is so specific that thiols and substituted thiols (methionine and cystine) can easily be distinguished.

Quantum Dot-Based Fluorometric Sensor for Hg(II) in Water Customizable for Onsite Visual Detection.

An easy naked-eye detection technique for mercuric ions in water using silanized quantum dots is demonstrated. Cadmium selenide quantum dots were synthesized and rendered water soluble by silica overcoating. The quantum dot emission was instantly turned off by the mercuric ions in the analyte, enabling visual detection.