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.

Gold nanomaterials have attracted considerable interest as vehicles for intracellular drug delivery. In our study, we synthesized three different shapes of methylpolyethylene glycol coated-anisotropic gold nanoparticles: stars, rods, and triangles. The cellular internalization of these nanoparticles by RAW264.7 cells was analyzed, providing a parametric evaluation of the effect of shape. The efficiency of cellular uptake of the gold nanoparticles was found to rank in the following order from lowest to highest: stars, rods, and triangles. The possible mechanisms of cellular uptake for the three types of gold nanoparticles were examined, and it was found that different shapes tended to use the various endocytosis pathways in different proportions. Our study, which has demonstrated that shape can modulate the uptake of nanoparticles into RAW264.7 cells and that triangles were the shape with the most efficient cellular uptake, provides useful guidance toward the design of nanomaterials for drug delivery.

Lead halide perovskite (PVK) has been deemed as a promising photocatalyst alternative because of its remarkable photoelectrical properties; however, the severe charge recombination has limited its catalytic activity. Herein, we report a PVK-based Z-scheme heterojunction, a-Fe 2 O 3 /Amine-RGO/CsPbBr 3 , for highefficiency CO 2 reduction in the presence of H 2 O. By delicately controlling the interfacial interaction, effective Z-scheme electron transfer from a-Fe 2 O 3 to CsPbBr 3 is built, leading to boosted charge separation and prolonged carrier lifetime, as confirmed by electron spin resonance (ESR), transient absorption (TA) spectra, etc. The impactful spatial separation of photo-generated carriers in Z-scheme system finally enables an 8.3-fold enhancement in photocatalytic performance as compared to CsPbBr 3 . A stable product yield of 469.16 mmol g À1 and an electron consumption yield of 3,132.46 mmol g À1 are achieved. This work is expected to provide deep insights into boosting the photocatalytic performance of PVK by modulating the charge carrier dynamics.

Heterojunction engineering has played an indispensable role in the exploitation of innovative artificial materials with exceptional properties and has consequently triggered a new revolution in achieving high-performance optoelectronic devices. Herein, an intriguing halide perovskite (PVK) and metal dichalcogenide (MD) heterojunction, i.e., a lead-free Cs2SnI6 perovskite nanocrystal/SnS2 nanosheet hybrid, was fabricated in situ for the first time. Comprehensive investigations with experimental characterizations and theoretical calculations demonstrate that cosharing of the Sn atom enables intimate contact in the Cs2SnI6/SnS2 hybrid together with a type II band alignment structure. Additionally, ultrafast carrier separation between SnS2 and Cs2SnI6 has been observed in the Cs2SnI6/SnS2 hybrid by transient absorption measurements, which efficiently prolongs the lifetime of the photogenerated electrons in SnS2 (from 1290 to 3080 ps). The resultant spatial charge separation in the Cs2SnI6/SnS2 hybrid evidenced by Kelvin probe force microscopy (KPFM) significantly boosts the photocatalytic activity toward CO2 reduction and the photoelectrochemical performance, with 5.4-fold and 10.6-fold enhancements compared with unadorned SnS2. This work provides a facile and effective method for the in situ preparation of PVK-MD heterojunctions, which may significantly stimulate the synthesis of various perovskite-based hybrid materials and their further optoelectronic applications.