Hierarchical mesoporous carbon sphere@nickel cobalt sulfide core–shell structures and their electrochemical performance

Biomass-Derived Carbon Materials: Controllable Preparation and Versatile Applications

Biomass-derived carbon materials (BCMs) are encountering the most flourishing moment because of their versatile properties and wide potential applications. Numerous BCMs, including 0D carbon spheres and dots, 1D carbon fibers and tubes, 2D carbon sheets, 3D carbon aerogel, and hierarchical carbon materials have been prepared. At the same time, their structure-property relationship and applications have been widely studied. This paper aims to present a review on the recent advances in the controllable preparation and potential applications of BCMs, providing a reference for future work. First, the chemical compositions of typical biomass and their thermal degradation mechanisms are presented. Then, the typical preparation methods of BCMs are summarized and the relevant structural management rules are discussed. Besides, the strategies for improving the structural diversity of BCMs are also presented and discussed. Furthermore, the applications of BCMs in energy, sensing, environment, and other areas are reviewed. Finally, the remaining challenges and opportunities in the field of BCMs are discussed.

Self-Supported Ternary Ni-S-Se Nanorod Arrays as Highly Active Electrocatalyst for Hydrogen Generation in Both Acidic and Basic Media: Experimental Investigation and DFT Calculation

In this study, a novel three-dimensional self-supported ternary NiS-Ni₉S₈-NiSe nanorod (NR) array cathode has been successfully in situ constructed by a two-step hydrothermal route. When applied to hydrogen evolution, the synthesized NiS-Ni₉S₈-NiSe-NR electrode demonstrates optimized electrocatalytic activity and long-term durability, only requiring overpotentials as low as 120 and 112 mV to drive 10 mA cm^-2 for hydrogen evolution reaction in 0.5 M H₂SO₄ and 1.0 M KOH, respectively. Density functional theory calculation reveals that after Se doping Se 3d orbitals are bonded to Ni 3d orbitals and S p orbitals near Fermi level, attesting a significant electron transfer between nickel and selenium atoms. The success of enhancing the electrocatalytic performance via introducing the Se dopant holds great promise for the potential optimization of other transition-metal compounds in highly efficient electrochemical water splitting for large-scale hydrogen production.

Electrochemically growth-controlled honeycomb-like NiMoO4 nanoporous network on nickel foam and its applications in all-solid-state asymmetric supercapacitors

A honeycomb-like NiMoO₄ nanoporous network electrode was synthesized on nickel foam using an electrodeposition method and used for the fabrication of asymmetric supercapacitors (ASCs).

Modified chemical synthesis of MnS nanoclusters on nickel foam for high performance all-solid-state asymmetric supercapacitors

Novel MnS nanoclusters were synthesized on nickel foam (NF) using a successive ionic layer adsorption and reaction (SILAR) method.