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The selective hydrogenation of crotonaldehyde has gained considerable attention owing to its industrial applications for producing fine chemicals. Understanding the hydrogenation mechanism from density functional theory (DFT) calculations can provide insights for designing catalysts with high selectivities toward the target products. Among contemporary theoretical investigations of the hydrogenation, the calculated selectivities are not in agreement with the experimental results. Herein, a SiO 2 -supported Pt nanocluster is developed, and it is used to investigate the selective hydrogenation of crotonaldehyde. The nanocluster model is used to obtain free energy barriers from DFT calculations, and these are used to build a microkinetic model. The theoretical selectivity values for the products are in agreement with the experimental results. According to the density of state analysis, this is directly attributed to the more accurate d-band width from the Pt cluster. The contribution of each step to the final product is identified and can be used to intensify the process of generating the target product.

Research on zinc-ion batteries (ZIBs) with manganese-based cathodes has been severely hindered by their poor cycle stability. This study explores the fundamental parameters that affect the cycle stability of battery systems from a structural stability perspective. MnO2 electrodes with different classical morphologies and sizes were synthesized via a temperature-controlled coprecipitation strategy. The effects of the morphology and size of the MnO2 on the overall electrical properties and kinetics of ZIBs were analyzed and compared. The one-dimensional nanofibrous α-MnO2 produced using this method exhibited the most stable nanostructure with a favorable aspect ratio, which resulted in faster chemical kinetics. A more uniform particle distribution and better aspect ratios not only enabled a faster ion migration rate but also affected the remolding of the anode morphology. After 2000 cycles at a high current density of 1 A g–1, the material maintained an excellent discharge-specific capacity, highlighting it as a promising electrode material for ZIBs. The construction of nanoenergy materials with controllable morphologies and sizes will significantly advance battery applications.

Cathodic catalytic activity and interfacial mass transfer are key factors for efficiently generating hydrogen peroxide (H2O2) via a two-electron oxygen reduction reaction (ORR). In this work, a carbonized carboxymethyl cellulose (CMC)–reduced graphene oxide (rGO) synthetic fabric cathode was designed and constructed to improve two-electron ORR activity and interfacial mass transfer. Carbonized CMC exhibits abundant active carboxyl groups and excellent two-electron ORR activity with an H2O2 selectivity of approximately 87%, higher than that of rGO and other commonly used carbonaceous catalysts. Carbonizing CMC and the agglomerates formed from it restrain the restacking of rGO sheets and thus create abundant meso/macroporous channels for the interfacial mass transfer of oxygen and H2O2. Thus, the as-constructed carbonized CMC–rGO synthetic fabric cathode exhibits exceptional H2O2 electrosynthesis performance with 11.94 mg·h–1·cm–2 yield and 82.32% current efficiency. The sufficient active sites and mass-transfer channels of the cathode also ensure its practical application performance at high current densities, which is further illustrated by the rapid organic pollutant degradation via the H2O2-based electro-Fenton process.