Networked pitch-derived semicoke-coated Ni foam with synergistic photon and fluidic management for highly efficient solar steam generation

Three-dimensional (3D) Ni foam evaporators integrated with self-assembled semiconductor photothermal materials are garnering significant interest for interfacial solar steam generation (ISSG) owing to tunable energy bands, porous structures and excellent wettability. Nevertheless, the widespread deployment of these evaporators is constrained by high cost and the inherent instability of semiconductor materials, which are susceptible to oxidation or photo-corrosion under prolonged light exposure. Herein, a robust networked pitch-derived semicoke-coated Ni foam evaporator (NPSC@NF-1) is fabricated by a facile dip-coating strategy. In NPSC@NF-1, the 3D porous structure of the Ni foam and the network structure of pitch-derived semicoke synergistically enhance light absorption through internal multiple scattering of incident light. Additionally, the tuned pore size distribution and tailored wettability of NPSC@NF-1 collectively optimize water supply through Laplace pressure-driven capillary action, achieving efficient photothermal energy conversion and enhanced evaporation performance. Consequently, NPSC@NF-1 achieved a high evaporation rate of 1.48 kg m⁻² h⁻¹ and a photothermal conversion efficiency of 83.92 % under 1 sun illumination. The simple fabrication process of NPSC@NF-1 not only facilitates the development of high-performance evaporators but also promotes the efficient utilization of pitch resources.