Copper-Nanoparticle-Decorated Hydrothermal Carbonaceous Carbon–Polydimethylsiloxane Nanocomposites: Unveiling Potential in Simultaneous Light-Driven Interfacial Water Evaporation and Power Generation

This study introduces a hydrothermal synthesis method that uses glucose and Cu2+ ions to create a Cu-nanoparticle (NP)-decorated hydrothermal carbonaceous carbon hybrid material (Cu–HTCC). Glucose serves both as a reducing agent, efficiently transforming Cu2+ ions into elemental Cu nanostructures, and as a precursor for HTCC microstructures. An enhanced plasmon-induced electric field resulting from Cu NPs supported on microstructure matrices, coupled with a distinctive localized π-electronic configuration in the hybrid material, as confirmed by X-ray photoelectron spectroscopic analysis, lead to the heightened optical absorption in the visible–near-infrared range. Consequently, flexible nanocomposites of Cu–HTCC/PDMS and Cu–HTCC@PDMS (PDMS = polydimethylsiloxane) are designed as two-dimensional and three-dimensional structures, respectively, that exhibit broad-spectrum solar absorption. These composites promise efficient photo-assisted thermoelectric power generation and water evaporation, demonstrating commendable mechanical stability and flexibility. Notably, the Cu–HTCC@PDMS composite sponge simultaneously exhibits commendable efficiency in both water evaporation (1.47 kg/m2/h) and power generation (32.1 mV) under 1 sun light illumination. These findings unveil new possibilities for innovative photothermal materials in diverse solar-driven applications.