Sputter-deposited nickel nanoparticles on Kevlar fabrics with laser-induced graphene for efficient solar evaporation

Solar desalination is a current green energy process in water treatment. In this process, producing solar evaporation materials is essential to the widespread diffusion of solar desalination technology. However, balancing cost and high evaporation performance poses an ongoing challenge. In this study, we prepared a self-floating fabric evaporator using a simple two-step method, first forming laser-induced graphene (LIG) by laser scribing technique on the surface of aramid fabric and then depositing nickel nanoparticles (NiNPs) on the LIG surface using magnetron sputtering. The porous aramid fabric provides a high water flux, and the NiNPs/LIG endows the aramid fabric with excellent photothermal properties. Compared with LIG alone, the addition of nickel nanoparticles with plasma effect can effectively reduce the heat loss due to light reflection from graphene, enhance light absorption, and efficiently achieve photothermal conversion. Under 1 solar irradiation (100 mW cm−2), the water evaporation rate of NiNPs/LIG up to 1.608 kg·m−2·h−1 with a conversion rate of 93 %. In addition, NiNPs/LIG formed a stable superhydrophobic structure on the fabric surface, effectively preventing salt deposition during desalination. More importantly, NiNPs/LIG has more excellent antibacterial properties than conventional solar desalination materials. Therefore, NiNPs/LIG has multiple water purification potentials in desalination and is a promising new solar absorber that deserves future attention.