Jinlong Jiang

In this study, ZrCuN coatings, with doping Cu into ZrN coating, are prepared by a co‐deposition method, which has enabled the benefits of cathodic arc and high‐power impulse magnetron sputtering (HiPIMS) techniques. This study systematically investigates how Cu doping affects the microstructure, mechanical properties, and tribological behavior of the coatings. The results indicate that the co‐deposition process can effectively inhibit the generation of large particles during arc deposition, thereby improving the density and uniformity of the coatings. The frictional performance of the coatings was enhanced by the incorporation of Cu due to its self‐lubricating property. With the doping of Cu, the wear mechanisms of the ZrCuN coating changes intense abrasive and adhesive wear to slight adhesive wear. The wear rate of ZrCuN coatings is effectively reduced as compared with ZrN coatings by arc deposition. At a HiPIMS power of 1.5 kW, the wear rate was just 4.95 × 10⁻⁶ mm³N⁻¹ m⁻¹, which shows a 78.8% reduction as compared to that of ZrN coatings. This study provides a promising approach for the development of self‐lubricating coatings with superior wear resistance.

In this study, monodispersed NiSe@Ni particles were successfully anchored on graphene sheets by electroless nickel plating combined with a chemical-vapor-reaction process, in which the nickel particles were first deposited onto graphene sheets and subsequently transformed in situ into NiSe@Ni at an elevated temperature. The obtained product showed a unique multi-dimensional coupling structure, namely, monodispersed NiSe@Ni particles (0 D) anchored on graphene sheets (2 D), which enabled maximum synergy on the specific surface area, conductivity, and the electrochemical activity of NiSe, Ni, and graphene multi-phases. The NiSe@Ni/graphene composite showed a specific capacity of 302 mAh g⁻¹ at a current density of 1 A g⁻¹ in a potassium-hydroxide-electrolyte solution. Meanwhile, the hybrid supercapacitor of NiSe@Ni/graphene//AC exhibited a high energy density of 68.0 Wh kg⁻¹ at 803.0 W kg⁻¹ and maintained 72.53% of the initial capacity after 10,000 cycles at a current density of 10 A g⁻¹.

Sulfonated carbon is a green, solid acid catalyst but its surface area, separation, and recovery after utilization need to be improved. The objective of the present study was to provide an environmentally friendly and economical method to prepare magnetic sulfonated carbon composite catalyst with a large surface area using palygorskite (Plg) as the support. A magnetic sulfonated carbon/Fe₃O₄/Plg composite catalyst was prepared via simultaneous calcination and sulfonation of the mixture of source, p-toluenesulfonic acid (TsOH), and Fe₃O₄/Plg. Fe₃O₄ nanoparticles and Plg nanorods were encased by a carbon layer derived from sucrose and TsOH. The composite catalyst exhibited good magnetic properties and high catalytic performance for the esterification of oleic acid with methanol. Oleic acid conversion reached 88.69% after the first catalytic cycle. Plg nanorods replaced sucrose and increased the catalyst’s surface area. The introduction of Fe₃O₄ nanoparticles improved further the acid content and oleic-acid conversion and achieved 70.31% after five cycles. The catalyst was recycled easily using an external magnetic field and its magnetic property remained unchanged due to the protection of the carbon layer.

Carbon nanotubes and g-C ₃ N ₄ synergistically optimize the electrical conductivity and spatial structure of CoSe ₂ , thus improving the performance of supercapacitors.

Sulfonated carbon is a ‘green,’ solid-acid catalyst. For applications purposes, its surface area needs to be improved and its preparation needs to be made environmentally friendly. The objective of the present study was to provide a green and economical method of preparing a sulfonated carbon catalyst by using palygorskite (Plg) fiber as a support for sulfonated carbon. Sulfonated carbon/palygorskite solid-acid catalyst (SC-Plg) was synthesized via one-step carbonization-sulfonation by mixing palygorskite with sucrose as the carbon source and p-toluenesulfonic acid as the sulfonating agent. The catalyst was characterized by SEM, EDX, TEM, FTIR, and nitrogen adsorption-desorption isotherms. The results indicated that sucrose-derived carbon was loaded uniformly on the surface of Plg fibers and formed the SC-Plg catalyst. The inexpensive Plg fibers could replace sucrose-derived carbon and increase the surface area of the resulting catalyst. The SC-Plg shows significant catalytic performance and excellent stability when used in the esterification of oleic acid with methanol. The conversion of oleic acid reached 68.09%, even after five cycles. This work paves the way for the development of highly active, carbon-based, solid-acid composite catalysts using a natural Plg nanofiber template.