The efficient production of hydrogen as a clean energy carrier relies on the performance optimization of electrocatalysts for the hydrogen evolution reaction (HER).Although platinum (Pt)?based catalysts exhibit exceptional HER activity,their high cost and stability issues can be mitigated through rational design of the support material.Nickel hydroxide (Ni(OH)?) has emerged as a promising support due to its unique proton conductivity,interfacial modulation properties,and stabilizing effects on Pt. However,a systematic understanding of the structure–activity relationship between Ni(OH)? supports and Pt nanoparticles,as well as the impact of synthesis parameters on catalytic performance,remains lacking.This study focuses on the regulation of Ni(OH)? support phase evolution and Pt interfacial growth behavior by hydrothermal synthesis temperature.By analyzing the structure–performance relationship through the synthesis parameter–microstructure–catalytic performance correlation mechanism),the synergistic effects of temperature on the crystallinity of the support,Pt particle size distribution,and interfacial electronic structure were elucidated.Experimental results indicate that the Pt@Ni(OH)? catalyst synthesized at 100 ℃ exhibits outstanding HER activity in 1 mol/L KOH electrolyte,with overpotentials of only 5 mV at 10 mA/cm2 and 62 mV at 100 mA/cm2,along with a Tafel slope of 70.0 mV/dec.After 50 hours of continuous operation,the electrode maintains nearly unchanged HER performance,demonstrating remarkable stability.

As palladium(Pd) catalysts have poor selectivity to the target product in the selective hydrogenation process,a series of PdM/C bimetallic alloy catalysts were synthesized by the simple co?reduction of second metals (M=Mn,Fe,Co,Ni) and Pd. With 3?nitrostyrene as the model molecule and H₂ as the hydrogen source, this study investigated the effect of second metals on the selective hydrogenation performance of Pd?based catalysts. The Pd?based catalysts were characterized and tested by methods including X?ray diffraction (XRD), transmission electron microscope (TEM),and gas chromatography.The results reveal that when pure Pd/C is used as the catalyst, the conversion reaches 100% for 1.5 h, but the selectivity of 3?nitrophenylethane is only 29%, and the selectivity of 3?aminophenylethane is 71%. After the introduction of second metals, the selectivity of 3?nitrophenylethane is increased to 75%~100% under the same conditions. Among them,PdFe/C has the best performance(100%) in the hydrogenation of 3?nitrostyrene to 3?nitrophenylethane, and high conversion(100%) and selectivity (99%) of 3?nitrophenylethane can still maintain after ten reaction cycles. It can effectively avoid over?hydrogenation and realize the selective hydrogenation of 3?nitrostyrene to 3?nitrophenylethane.

The activation of peroxymonosulfate (PMS) by cobalt?based catalysts has the advantages of high catalytic activity, simple operation, easy recyclability, and low cost. Hence, it has attracted much attention in the field of advanced oxidation processes in recent years. This paper reviewed typical methods for the synthesis of cobalt?based catalysts, including solid phase, gas phase, and liquid phase methods. Several types of cobalt?based catalysts for PMS activation, including cobalt oxides with special morphologies, supported cobalt catalysts, and cobalt?based composite metal oxides, were summarized. The applications of these cobalt?based catalysts in environmental remediation via PMS activation were also elaborated, such as the degradation of organic dyes, endocrine?disrupting chemicals, and pharmaceutical and personal care products. Finally, the current shortcomings of cobalt?based catalysts in PMS activation were summarized, and some future research directions in this area were proposed.