Preparation of sulfur-doped porous carbon from polyphenylene sulfide waste for photothermal conversion materials to achieve solar-driven water evaporation†

Abstract

In recent years, solar-driven photothermal water evaporation technology for seawater desalination and wastewater treatment has developed rapidly, which is of great significance for addressing the issue of freshwater scarcity. However, due to the high costs associated with the manufacturing, maintenance, and operation of such devices, their application remains challenging in remote and resource-scarce regions. Due to its excellent light absorption capability in the near-infrared region, high hydrophilicity, and stable chemical properties, coupled with the low cost of recycling waste carbonized polyphenylene sulfide, this material is an excellent choice as a photothermal material for solar-driven water evaporation devices. Ordinary wood in nature usually has a highly regenerative porous structure, which is a natural water transport channel that facilitates the transport of water from the bottom to the top, allowing it to be rapidly converted into vapor. Based on this characteristic, this article innovatively proposes to prepare waste polyphenylene sulfide from porous carbonized materials (KCP) as the photothermal conversion material for novel photothermal water evaporation devices, achieving solar-driven water evaporation. This material efficiently facilitates the conversion between solar and thermal energies and exhibits excellent hydrophilicity, thereby enabling the rapid utilization of absorbed solar energy for water evaporation on the surface of the evaporator. In this study, a porous carbonized polyphenylene sulfide photothermal water evaporator (KCP-wood) was fabricated by using freeze-drying and in situ coating to load the photothermal conversion material onto a wood substrate. Under simulated one-sun irradiation, this evaporator achieved a water evaporation rate of 2.41 kg m⁻² h⁻¹ and a photothermal conversion efficiency of 91.3%. Additionally, a systematic study was conducted on the photothermal performance of various light–water evaporators, encompassing photothermal conversion efficiency, stability, thermal conductivity, and anti-fouling capabilities. Finally, the practical performance of the light–water evaporator under various environmental conditions was validated, demonstrating its excellent stability and durability. It is capable of effectively applying to high-efficiency water resource utilization and solar energy conversion fields.