Synergistic Interaction of Ternary Ni−Co−Cu Chalcogenides Confined in Nanosheets Array to Advance Supercapacitors and Solar Steam Generation

Copper foam (CF)-supported 3D nanosheets array composed of ternary Ni−Co−Cu chalcogenides are prepared by a simple in situ formation process. Specifically, a highly electroactive Ni−Co binary sulfide in nanosheets is synthesized against the CF backbone, whereas the copper species migrate from the CF to the Ni−Co nanosheets, leading to the in situ formation of the ternary metallic sulfide (Ni−Co−Cu−S, NCCS). Due to the synergistic interaction of Ni, Co, and Cu sulfides confined in nanosheets, this NCCS material demonstrates good mechanical robustness, a large surface area, and enhanced electric conductivity. As a result, the NCCS exhibits a high specific capacitance (750 mF cm⁻² at 100 mA cm⁻²) with good cycling performance (97.14% after 10 000 cycles) when used as supercapacitor electrodes. In addition, the 3D porous hierarchical nanostructure of NCCS provides nanoconfined water molecule channels to achieve high-yield solar steam generation, delivering an enhanced evaporation rate of 2.48 kg m⁻² h⁻¹ under 1 sun irradiation.