Eco-friendly and recyclable evaporator based on discarded cigarette filters for high-efficiency and stable solar desalination

Solar steam generation is a promising technology to realize efficient and green desalination with a minimized carbon footprint. Discarded cigarette filters (CFs) cause significant harm to the environment but have good recycling potential for solar steam generation. In this study, an efficient thermally-positioned material (AC-CF), which uses renewable cellulose acetate CFs and an acetylene carbon black (AC) coating as an absorber, was developed for application as a solar steam generator. The AC-CF exhibited superhydrophilic characteristics and extensive solar absorption (approximately 100%). These properties enable the resulting AC-CF to exhibit rapid water transport and a strong photothermal conversion ability, with an outstanding evaporation rate of 1.81 kg m −2  h −1 under 1 sun illumination. The evaporator can remove most impurities and dye molecules during outdoor operation. Subsequently, the AC-CF evaporator was dissolved and recycled using N, N-dimethylformamide, and the recycling method yielded good results. This method for preparing absorbers reduces manufacturing costs and guides the potential practical application of recycled polymer resources using discarded CFs.