Water-flow-induced high-efficiency solar vapor generation and electricity collection

Abstract

The interface photothermal evaporator still face challenges such as unstable operation, low evaporation efficiency, and insufficient energy utilization, particularly in high-concentration saltwater environments. This study proposes integrating a flow-induced power generation device within a photothermal-driven interface water evaporation system to address these issues. By leveraging the negative charge of carbon nanoparticles, a dual-electrode microchannel structure was optimized to establish an in-plane potential difference along the water transport path. The performance of the synchronized evaporation-flow-induced power generation system, with the carbon nanoparticle fabric as the core component, was thoroughly investigated, including its photothermal interface evaporation and power generation capabilities. Additionally, the controllability of the moisture content and water supply rate of the evaporation interface was achieved by adjusting the contact angle between the carbon nanoparticle fabric and bulk water, as well as the width of the water supply non-woven fabric. The synchronized evaporation-power generation system achieved an interface water evaporation rate of 1.44 kg m−2 h−1 and an output power density of 0.3 mW m−2 under 1 sun illumination (at a solar flux of q = 1 kW m−2). This study successfully obtained additional electrical energy output while prioritizing the evaporation rate, providing new insights for maximizing the energy efficiency of interfacial photothermal evaporation systems.