Optimizing the performance of electrode materials to improve the energy density of supercapacitors is the focus of current research. Construction and design with complex yolk-shell structure, as a supercapacitor electrode material, are of great significance and challenging. Herein, a self-sacrificing template strategy was used to construct uniform carbon-modified NiS/NiS₂ yolk-shell spheres using a Ni-based metal–organic framework (Ni-soc-MOF) as the precursors. Especially, the carbon shells produced by the pyrolysis of the organic ligand can improve mechanical stability and electron conductivity. Therefore, the as-obtained NiS/NiS₂@C nanocomposites display a high specific capacity (1082 C g⁻¹at 1 A g⁻¹) and outstanding cycling stability (85% capacity retention after 5000 cycles). In addition, a hybrid supercapacitor device based on the yolk-shell NiS/NiS₂@C nanocomposite and porous carbon can deliver a high energy density of 56.2 Wh kg⁻¹ at 800 W kg⁻¹, while exhibiting an excellent capacity retention of 86% after 10,000 charge/discharge cycles, demonstrating the promising potential of yolk-shell NiS/NiS₂@C nanocomposites via Ni-soc-MOF-derived route in practical application.

Carbon-based functional materials are deemed to be excellent candidates to adsorb contaminants from wastewater, yet their catalytic roles in advanced oxidation processes (AOPs) are still ambiguous. Therefore, four functional carbons (SPFCx) were fabricated in this study under various pyrolysis temperatures by using Sedum plumbizincicola (SP) residues (a kind of phytoremediation plant) as the precursors. Notably, SPFC800 exhibited the best adsorption capacity (q_e = 26.081 mg g⁻¹) toward bisphenol A (BPA) due to its having the largest specific surface area (121.57 m² g⁻¹). By injecting peroxymonosulfate (PMS, 5.0 mM), BPA (10 mg L⁻¹) could be completely removed within 70 min. More importantly, the BPA removal was stable and effective even in complex wastewater. Interestingly, radicals played minor roles in the SPFC800/PMS system, while nonradical mechanisms (i.e., ¹O₂ and electron-transfer regime) were responsible for the BPA elimination, which was verified by quenching tests, solvent exchange experiments (H₂O₂→D₂O), and electrochemical experiments. Overall, this work may provide a facile and green method for BPA contaminated-wastewater purification and promote the application of AOPs in environmental remediation.