Halide perovskite quantum dots (QDs), primarily regarded as optoelectronic materials for LED and photovoltaic devices, have not been applied for photochemical conversion (e.g., water splitting or CO reduction) applications because of their insufficient stability in the presence of moisture or polar solvents. Herein, we report the use of CsPbBr QDs as novel photocatalysts to convert CO into solar fuels in nonaqueous media. Under AM 1.5G simulated illumination, the CsPbBr QDs steadily generated and injected electrons into CO, catalyzing CO reduction at a rate of 23.7 μmol/g h with a selectivity over 99.3%. Additionally, through the construction of a CsPbBr QD/graphene oxide (CsPbBr QD/GO) composite, the rate of electron consumption increased 25.5% because of improved electron extraction and transport. This study is anticipated to provide new opportunities to utilize halide perovskite QD materials in photocatalytic applications.

The proper energy band structure and excellent visible-light responses enable halide perovskites as potential photocatalysts for CO 2 reduction, but the conversion efficiency is still low due to the serious radiative recombination, low CO 2 capturing ability, and poor stability. Here we illustrate the design and synthesis of a halide perovskite@metal−organic framework (MOF) composite photocatalyst with enhanced CO 2 reduction activity. A facile in situ synthetic procedure is employed to directly grow a zinc/cobalt-based zeolitic imidazolate framework (ZIF) coating on the surface of CsPbBr 3 quantum dots. The CsPbBr 3 @ZIF composite shows largely improved moisture stability, CO 2 capturing ability, and charge separation efficiency. Moreover, the catalytic active Co centers in ZIF-67 can further accelerate the charge separation process and activate the adsorbed CO 2 molecules, which leads to enhanced catalytic activity for gaseous CO 2 reduction. This work would provide new insight for designing excellent perovskite/MOF-based catalysts.

Low‐dimensional luminescent lead halide perovskites have attracted tremendous attention for their fascinating optoelectronic properties, while the toxicity of lead is still considered a drawback. Herein, we report a novel lead‐free zero‐dimensional (0D) indium‐based perovskite (Cs2InBr5⋅H2O) single crystal that is red‐luminescent with a high photoluminescence quantum yield (PLQY) of 33 %. Experimental and computational studies reveal that the strong PL emission might originate from self‐trapping excitons (STEs) that result from an excited‐state structural deformation. More importantly, the in situ transformation between hydrated Cs2InBr5⋅H2O and the dehydrated form is accompanied with a switchable dual emission, which enables it to act as a PL water‐sensor in humidity detection or the detection of traces of water in organic solvents.

Background: Head and neck cancer contains cancer stem cells (CSCs) characterized by a high level of CD44 expression. Results: We discovered a new hyaluronan (HA)-CD44-mediated Oct4, Sox2, and Nanog pathway that regulates miR-302 production in CSCs. Conclusion: HA-CD44v3-activated Oct4-Sox2-Nanog signaling and miR-302 play a pivotal role in CSC functions. Significance: This information should provide new drug targets to treat head and neck cancer.

Owing to the 3D scaffolds, porous nanosheets, and strong synergistic effect of Mo and W atoms, the Mo–W–P hybrid behaves as an efficient electrocatalyst for the hydrogen evolution reaction.