High-efficiency solar-driven water purification enhanced by the in-plane temperature gradient and hydrated ions

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 481; p. 148364
• Main Authors: Ding, Renjie, Xiong, Jinhua, Yan, Qian, Li, Pengyang, Zhao, Xu, Chen, Zhong, Liu, Zonglin, Lian, Huanxin, Tang, Zhigong, Du, Shanyi, Peng, Qingyu, He, Xiaodong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2024
• Subjects: Acid purification; Desalination; Graphene oxide; Polyaniline; Ti3C2Tx MXene; Graphene oxide; Ti3C2Tx MXene; Polyaniline; Desalination; Acid purification
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2023.148364

[Display omitted] •The unique in-plane temperature gradient formed by the redesign of SVG device.•High evaporation rate of 6.40 kg m−2 h−1 with high evaporation efficiency of 243.8 % in pure water.•High evaporation rate of 6.75 kg m−2 h−1 in pH = 4.0 aqueous acid.•Excellent stability and reusability in acid purification. Solar-driven water purification has become a promising way to overcome the freshwater crisis because of its environmentally-friendly features. Improving the evaporation rate and evaporation efficiency are eternal topics. In this work, we redesign the solar-driven vapor generation (SVG) device and a unique in-plane temperature gradient is established due to the oriented water transportation. The input energy is maximized and the superb evaporation rate of 6.40 kg m−2 h−1 with an efficiency of 243.8 % is achieved. By investigating the hydration state in NaCl solution and aqueous acid, the interaction mechanism between hydrated ions and non-woven fabrics is developed. Owing to the increased intermediate water proportion, the evaporation rate of the SVG device in 5 wt% NaCl solution can reach 6.38 kg m−2 h−1, which is almost the same as that in DI water. Moreover, the unique reversible doping properties make the non-woven fabrics a reusable and stable volatile acid purifier. The evaporation rate in pH = 4.0 aqueous acid can be enhanced to 6.75 kg m−2 h−1, while the generated water maintains a pH higher than 6.5. Our work provides a new perspective for designing high-efficiency and multifunctional SVG devices.