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Carbonyl compounds serve as essential raw materials in the production of fine chemicals and pharmaceuticals. An economical and environmentally-friendly route to generating carbonyl compounds involves the catalytic oxidation of alcohols and hydrocarbons using heterogeneous catalysts. In this work, we synthesize a series of vanadium-doped ordered mesoporous zirconium oxophosphate (V/M-ZrPO) nanocomposites via a modified one-pot evaporation-induced self-assembly approach. Characterization results confirm the successful embedding of vanadium species into the framework of the M-ZrPO support. Dispersion of vanadium sites generates catalysts exhibiting enhanced performance for the selective oxidation of alcohols and hydrocarbons to carbonyl compounds. In particular, the 20 V/M-ZrPO catalyst demonstrates excellent reusability and broad substrate compatibility. Relative to established catalytic materials, the 20 V/M-ZrPO catalyst demonstrated superior performance across key metrics including product yield, reaction time, and recyclability. These findings highlight the promise of V/M-ZrPO nanocomposites as efficient and durable catalysts for sustainable carbonyl compound production. [ABSTRACT FROM AUTHOR]

In this work, a novel one‐step photo‐induced self‐assembly method have been applied to fabricate high dispersion CuO nanoparticles loading on the mesoporous silica (CuONP/MS). This method can effectively control the size of CuO metallic particles, having advantages of time saving, easy operation, and environmentally friendly. CuONP/MS with different Si/Cu molar ratio were used as heterogeneous Fenton‐like catalysts to remove methylene blue (MB) from wastewater with the help of H2O2. CuONP/MS(15), having proper copper doping amount, uniform CuO distribution in nano range and suitable Cu2+/Cu+ ratio, exhibited a higher activity (96 % within 20 min) and stability (80 % after five cycles of use) in MB degradation. CuONP/MS(15) could work in a wide range pH with low metal leaching concentration. Fluorescence(FL) results proved that it is more easily to form oxygen defect, which generate more surface hydroxyl groups as reaction sites for MB removal. One‐step photo‐induced self‐assembly method were proved to be an attractive alternative method to prepare metal loading mesosilica catalysts. CuONP/MS catalysts were efficient heterogeneous Fenton‐like system exemplified by the removal of organic pollutants from wastewater. [ABSTRACT FROM AUTHOR]

Extensive use of Al2O3 nanoparticles in consumer and industrial products has led to concerns about their potential environmental impacts in the recent years. In most studies concerning Al2O3 aggregation and disaggregation, more was to consider the single factor that influences their environmental behaviors. Understanding the combined abiotic factors that influence the fate, transport, and stability of nanoparticles in a complex aquatic system has become extremely important. Here, we reported and analyzed the major abiotic factors such as typical solution pH, electrolyte cations in different valences (Na+ and Ca2+), and the presence of humic acid (HA) that influence the stability, aggregation, and disaggregation behaviors of Al2O3 nanoparticles in a complex aquatic system. Dynamic light scattering technique combined with fluorescence spectroscopic analysis was used to explore the aggregation mechanisms. Experimental results indicated that Al2O3 nanoparticle stability was mainly controlled by the steric hindrance, van der Walls, and electrostatic interactions between HA and Al2O3 nanoparticles. Aggregation kinetics and attachment efficiency studies induced by the addition of Na+ and Ca2+ cations confirmed that divalent electrolytes could reduce the large energy barrier between the charged colloidal particles more efficiently, and induce a more aggressive aggregation of the particles. Additionally, the bridging effect of HA with Ca2+ was also an important mechanism for the aggregation enhancement, which had been confirmed by the fluorescence excitation-emission matrix (EEM) spectra analysis. These findings are useful in understanding the environmental challenges of inorganic colloidal particles in natural environments. [ABSTRACT FROM AUTHOR]

Perovskite (La 0.8 Sr 0.2 ) 1-x Mn 1-x Ir x O 3 (x = 0 (LSM) and 0.05 (LSMI)) nanoparticles with particle size of 20-50 nm are prepared by the polymer-assisted chemical solution method and demonstrated as high performance bifunctional oxygen catalyst in alkaline solution. As compared with LSM, LSMI with the A-site deficiency and the B-site iridium (Ir)-doping has a larger lattice, lower valence state of transition metal, and weaker metal-OH bonding; therefore, it increases the concentration of oxygen vacancy and enhances both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). LSMI exhibits superior ORR performance with only 30 mV onset potential difference from the commercial Pt/C catalyst and significant enhancement in electrocatalytic activity in the OER process, resulting in the best oxygen electrode material among all the reported perovskite oxides. LSMI also exhibits high durability for both ORR (only 18 mV negative shift for the half-wave potential compared with the initial ORR) and OER process with 10% decay. The electrochemical results indicate that the A-site deficiency and Ir-doping in perovskite oxides could be promising catalysts for the applications in fuel cells, metal-air batteries, and solar fuel synthesis.