3d Graphite-Based Janus Membrane with Dual-Sided Evaporation for High-Efficiency Solar-Driven Water Purification

Abstract

Solar-driven interfacial evaporation (SDIE) is a low-carbon, sustainable, and highly efficient technology for freshwater production, emerging as a promising solution to global freshwater scarcity. However, it remains a central challenge for current development of photothermal interfacial materials that are facile-to-fabricate, scalable, and highly efficient. In this study, we have fabricated a three-dimensional graphite-based paper fiber Janus membrane (3D-GPFJM) photothermal interfacial evaporator. This evaporator is characterized by its low cost and ease of preparation through a simple coating and folding process. It displays superior photothermal performance with an evaporation rate of 3.35 kg/m²·h and a photothermal conversion efficiency of 91.29% under a light intensity of 1 kW·m⁻². It maintains a high evaporation rate of 2.49 kg/m²·h in 3.5 wt% NaCl simulated seawater, and retains a clean surface after prolonged continuous evaporation, demonstrating exceptional anti-salt crystallization capabilities. Therefore, the 3D-GPFJM offers a promising solution for solar-driven seawater desalination and high-salinity water treatment, with potential for application in sustainable water purification technologies.

Keywords: Solar-driven interfacial evaporation, 3D Janus membrane, Dual-sided evaporation, Anti-salt crystallization, Sustainable desalination