Analytical detection of the bioactive molecules dopamine, thyroxine, hydrogen peroxide, and glucose using CsPbBr perovskite nanocrystals.

Qualitative and quantitative detection of biologically important molecules such as dopamine, thyroxine, hydrogen peroxide, and glucose, using newer and cheaper technology is of paramount importance in biology and medicine. Anion exchange in lead halide perovskites, on account of its good emission yield, facilitates the sensing of these molecules by the naked eye using ultraviolet light. Simple chemistry is used to generate chloride ions from analyte molecules.

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.

Thin silica shell on AgPO nanoparticles augments stability and photocatalytic reusability.

Semiconductor photocatalysts are promising cost-effective materials for degrading hazardous organic contaminants in water. AgPO is an efficient visible-light photocatalyst for the oxidation of water and dye degradation. The excited AgPO photocatalyst uses a hole to oxidise water or organic contaminants except the electron, which reduces Ag to Ag.

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.

Manipulating the Self-Assembly of Phenyleneethynylenes under Vibrational Strong Coupling.

The chemical and physical properties of molecules and materials are known to be modified significantly under vibrational strong coupling (VSC). To gain insight into the effects of VSC on π-π interactions involved in molecular self-assembly, themselves sensitive to vacuum electromagnetic field fluctuations, the aggregation of two structural isomers (linear and V-shaped) of phenyleneethynylene under cooperative coupling was investigated. By coupling the aromatic C═C stretching band, the assembly of one of the molecules results in the formation of spheres as opposed to flakes under normal conditions.

CdSe-CdTe Heterojunction Nanorods: Role of CdTe Segment in Modulating the Charge Transfer Processes.

Heterojunction nanorods having dissimilar semiconductors possess charge transfer (CT) properties and are proposed as active elements in optoelectronic systems. Herein, we describe the synthetic methodologies for controlling the charge carrier recombination dynamics in CdSe-CdTe heterojunction nanorods through the precise growth of CdTe segment from one of the tips of CdSe nanorods. The location of heterojunction was established through a point-by-point collection of the energy-dispersive X-ray spectra using scanning transmission electron microscopy.