Multi-level pumping water system from bioengineering wood microstructure by self-growing mycelium for boosting photothermal evaporation efficiency

Abstract

Due to low cost, renewability, high porosity and eco-friendliness, wood has been widely used to design solar steam generation devices, displaying great promise for clean water production in desalination and wastewater treatment. However, cleaner preparation processes and efficient structure design of wood based interfacial evaporators still need further exploration and development. Here, we reported an eco-friendly bio-incising method of wood microstructure modulation to fabricate high-performance wood-based solar steam generator by creating multi-level pumping water system. Self-growing Trametes versicolor (TV) which is a kind of bothersome wood fungus was skillfully used to increase porosity of wood and form interweaved mycelia fibers on wood surface, achieving the resegmentation and transmission of water bodies. These water-absorbing cell fibers and porous wood substrate collectively form a multi-level pumping water system ensuring effective heat management and high water evaporation area. Coupling with densely dispersed polydopamine nanoparticles (PDA NPs) on the surface of TV fiber for light absorption enhancement, the designed wood based solar steam generator with a smallest thickness of 1 mm shows outstanding evaporation rate (1.61 kg·m⁻²·h⁻¹) and solar energy conversion efficiency (98.4 %) under simulated 1 sun irradiation. Moreover, the obtained clean water using as-prepared steam generator shows high removal rates both in simulated seawater and wastewater. This work presents a novel concept and green method for designing high-performance wood-based solar steam generator with multi-level pumping water system.