Despite Si-based materials and their derivatives have recently emerged as potential electrode materials in advanced energy conversion and storage applications, a review article has not been reported hitherto for Si-based supercapacitors. In this review, the representative progresses of Si-based materials have been illustrated including synthesis, properties, surface modification, and electrochemical properties. A variety of nanomaterials are presented regarding the electrode material design and booming device constructions. Effective strategies for the preparation of Si-based materials and their derivatives are summarized especially including silicon/silicon carbide nanowires, silicon substrates, silicon particles, three-dimensional silicon structures, and silicon-based doping materials. Meanwhile, the overall behaviors in supercapacitor application have been illustrated in terms of specific capacitance, rate capability, cycling life, and energy density. Furthermore, large-voltage microsupercapacitors are outlined for next-generation integration devices.

Facilitating the surface reconstruction of pre-catalysts has been considered an effective strategy for constructing low-cost and highly efficient OER electrocatalysts. Metal doping is a feasible way to activate the surface reconstruction, thus enhancing the OER performance. Herein, we report a facile hydrothermal method to synthesize a series of Zn-doped Ni-MOF on nickel foam (NiZn-MOF/NF) as promising pre-catalysts toward the oxygen evolution reaction (OER). The Zn leaching of NiZn-MOF/NF can promote the surface self-reconstruction of NiZn-MOF/NF into oxygen-vacancy-rich NiOOH after electrochemical activation. Benefiting from the optimized electronic structure, abundant defects, more accessible active sites, and enhanced electrical conductivity, the reconstructed metal oxyhydroxide hybrids exhibit better electrocatalytic activity than the catalysts transformed from Ni-MOF/NF without Zn doping. The optimized NiZn-MOF/NF-OH as an OER catalyst has an overpotential of 336 mV at 100 mA cm⁻², and a Tafel slope of 65.9 mV dec⁻¹, as well as stability over 12 h. This work reveals that Zn cation-doping/leaching induces the surface reconstruction of pre-catalysts for enhanced oxygen catalytic activity, which provides a new approach for the development of advanced electrocatalysts.

Hierarchical porous N-doped carbon spheres featuring a combination of micropores, mesopores and macropores as well as tuneable properties were synthesised using dopamine as a carbon precursor and triblock copolymers (F127, P123 and F127/P123 composites) as templates via direct polymerisation-induced self-assembly. The structures and textures of these materials were characterised using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N₂ adsorption–desorption isotherm analysis, Fourier-transform infrared spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. The sample synthesised at an F127:P123 molar ratio of 1:3 (NCS-FP3) exhibited the highest surface area (463 m²/g) and pore volume (0.27 cm³/g). The hydrophobic/hydrophilic molar ratios of the templates were adjusted to control the morphology of the corresponding micelles and hence the porous structures and morphologies of the carbon spheres, which exhibited high CO₂ capture capacities (2.90–3.46 mmol/g at 273 K and 760 mmHg) because of their developed microporous structures and N doping. Additionally, NCS-FP3 exhibited an outstanding electrochemical performance, achieving a high specific capacitance (328.3 F/g at a current density of 0.5 A/g) and outstanding cycling stability (99.2% capacitance retention after 10,000 cycles). These high CO₂ capture and electrochemical performances were ascribed to the beneficial effects of pore structures and surface chemistry features.