In situ laser-induced biomimetic 3D-arched graphene with grass-like structures for efficient seawater desalination

Abstract

Due to the growing severity of global freshwater shortages, solar seawater desalination technologies have gained increased attention from researchers. Although various two-dimensional (2D) evaporators have been developed for solar desalination, their performance is limited by the constraints of the 2D structure. Herein, we proposed an innovative strategy to in situ fabricate a three-dimensional (3D) arched graphene-based solar evaporator with a double-layer biomimetic structure directly on polyether sulfone (PES) film using laser direct writing technology. During the laser irradiation process, the graphene and arched structure were generated simultaneously, without requiring additional design and preparation steps. The processing parameters for the preparation of arched graphene were systematically investigated, alongside an in-depth analysis of its physical and chemical properties. This biomimetic structure, comprising both an arched structure and grass-like structure, synergistically enhanced the evaporation rate (2.42 kg m⁻² h⁻¹) and efficiency (89.7%) of the LIG-based evaporator. The fabricated evaporator exhibited excellent stability during continuous evaporation and performed well even in high-concentration NaCl solutions. The ion concentration in the purified water was significantly reduced, and the growth of garlic seedlings irrigated with purified water was markedly stronger than those irrigated with seawater, indicating its potential for agricultural applications.