CsPbBr3 quantum dots were precipitated in phosphate glasses through heat treatment. Controlled formation of CsPbBr3 quantum dots was realized by adjustment of heat‐treatment conditions. Absorption and photoluminescence spectra of CsPbBr3 quantum dots were tuned from 432 to 521 nm. Upon ultraviolet or blue light excitation, efficient photoluminescence from these CsPbBr3 quantum dots doped phosphate glasses was observed.

The photoluminescence properties of perovskite CsPbBr QDs embedded in glasses were investigated at cryogenic temperature in the range of 40-240 K. CsPbBr QDs with radii of 3.3 nm, 4.2 nm and 4.8 nm were precipitated in phosphate glasses using conventional thermal treatment. Photoluminescence (PL) integral intensities, bandgap energies and full with at half maximum of the PL bands of CsPbBr QDs showed a strong dependence on temperature. An exciton binding energy of ∼40 meV was derived from the temperature-dependent emission intensity. Optical phonon energy involved in the exciton-phonon interaction was found to be ∼56 meV, about three times as that of the single phonon energy. Exciton-phonon coupling strength and the lattice thermal expansion coefficient were strongly dependent on the size of CsPbBr QDs, and as a result, inflection temperature of the PL peak energies of CsPbBr QDs increased as the size increased.

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Hybrid photocatalysts of graphitic carbon nitride (g-C 3 N 4) and reduced graphene oxide (rGO) composites were prepared in one-pot via a thermal condensation of melamine with different amounts of graphene oxide (GO). As metal-free hybrids, the prepared photocatalysts presented enhanced performances in photooxidation of both methylene blue and phenol in water solutions under various light irradiations. The level of rGO significantly affected MB photodegradation efficiencies. The introduced graphene can improve the MB adsorption and optical absorption in visible light region, therefore enables the hybrids to efficiently degrade MB under visible light with wavelengths longer than 430 nm. The metal-free photocatalysts were also able to degrade phenol effectively and the effects of catalyst loading and initial phenol concentration were investigated. This study provided an efficient and environmentally benign photocatalyst for degradation of organic pollutants in water, with complete prevention of secondary contamination from metal-leaching.

A highly chemo- and regioselective [4 + 2] formal cycloaddition of (Z)-3-iodo allylic nucleophiles and allenamides catalyzed by palladium is reported.

Thermal stabilizers, lubricant, and plasticizers are three crucial additives for processing poly(vinyl chloride) (PVC). In this study, a new mannitol stearate ester-based aluminum alkoxide (MSE-Al) was designed and synthesized as a novel additive for PVC. The thermal stability and processing performance of PVC stabilized by MSE-Al were evaluated by the Congo red test, conductivity measurement, thermal aging test, ultravioletevisible (UV–Vis) spectroscopy test, and torque rheometer test. Results showed that the addition of MSE-Al could not only markedly improve the long-term thermal stability of PVC, but also greatly accelerate the plasticizing and decrease the balance torque, which demonstrated that MSE-Al possessed a lubricating property. Thus, MSE-Al was demonstrated to be able to provide tri-functional additive roles, e.g., thermal stabilizer, plasticizer, and lubricant. The test results for the thermal stability of PVC indicated that the initial whiteness of PVC stabilized by MSE-Al was not good enough, thus the synergistic effect of MSE-Al with zinc stearates (ZnSt2) on the thermal stability of PVC was also investigated. The results showed that there is an appreciable synergistic effect between MSE-Al and ZnSt2. The thermal stabilization mechanism and synergism effect of MSE-Al with ZnSt2 are then discussed.

Er3+ ions‐doped germano‐gallate oxyfluoride glass‐ceramic containing BaF2 nanocrystals was prepared through conventional melt quenching and subsequent thermal treatment method. X‐ray diffraction patterns and transmission electron microscope images confirmed the formation of BaF2 nanocrystals in glass‐ceramics. Preferential incorporation of Er3+ ions into the BaF2 nanocrystals were confirmed by the absorption spectra and emission spectra, and enhanced upconversion emission and infrared emission were observed. Relatively high transmittance in the mid‐infrared region indicated great potential of this germano‐gallate oxyfluoride glass‐ceramics as host materials for the efficient mid‐infrared emission from rare‐earth ions.

A signal amplification principle based on increased electrocatalytic reduction of H2O2 by the CDs-3D-PG-Pd@Au NCs using the mediated effect of Th.