A mechanically durable, excellent recyclable 3D hierarchical Ni3S2@Ni foam photothermal membrane

Solar-driven water evaporation is considered to be a viable and very efficient technology for fresh water production. Unfortunately, the photothermal membrane has a low absorptivity, low photothermal conversion and poor recyclability, which are difficult to meet the demands of self-floating solar driven evaporators in practical applications. Herein, a hierarchical nanostructure Ni3S2 has been prepared by in-situ growing method on Ni foam (NF), which shows excellent absorptivity, outstanding recyclable and high mechanically durable properties. The photothermal membrane was composed of hierarchical nanostructure Ni3S2@NF, which exhibited excellent solar absorption (93.13%) in the wavelength range of 250 -2500 nm and sustained anti-corrosion capacity for one month. In addition, the hierarchical nanostructure Ni3S2 @NF has good hydrophilicity and strong binding force, indicating this photothermal membrane exhibits good stability and outstanding photothermal conversion efficiency. An evaporation system based on 3D Ni3S2@NF membrane exhibited excellent water evaporation ability,the highest water evaporation rate (1.53 kg m-2 h-1) and the photothermal conversion efficiency (84.7%) under 1 sun illumination. In the desalination experiment, the water evaporation rate and photothermal conversion efficiency almost keep constant over 5 cycles tests and do not decrease compared with the experiment in pure water. This result demonstrated that the Ni3S2@NF membrane has shown good corrosion resistance and outstanding recyclability. Due to the simple preparation method, low cost, outstanding recyclability and high mechanical durability in the sea water, this Ni3S2@NF membrane have great potential for long-term solar distillation applications. (c) 2020 Institute of Process Engineering, Chinese Academy of Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Hierarchical nanostructure Ni3S2@NF membrane, prepared by in-situ growing method on Ni foam, exhibits excellent absorptivity, recyclability, and mechanical durability for solar-driven water evaporation. It shows high solar absorption, sustained anti-corrosion capacity, good stability, and outstanding photothermal conversion efficiency, making it suitable for long-term solar distillation applications.