Bioinspired Dual-Function Device Integrating Fog Harvesting and Hydro-To-Electricity Conversion for Sustainable Supply of Freshwater and Electricity

Abstract

Utilizing ubiquitous fog to engineer a dual-function device that integrates fog harvesting and hydro-to-electricity conversion, thereby overcoming geographical and hydrological constraints, provides an opportunity to promote sustainable freshwater and electricity supply. However, inefficiency remains the key challenge to the advancement of fog energy development and practical applications. Herein, a bio-inspired dual-function device (BDFD) integrating efficient fog harvesting and a solid-liquid triboelectricity nanogenerator is developed. Specifically, biomimetic fog-water collector (BFWC) is designed inspired by the excellent fog-catching capability of Cactus and the ultra-fast water transport of Sarracenia. BFWC is then combined with a solid-liquid triboelectric nanogenerator to develop the BDFD. Additionally, the mechanism by which the structural parameters of BFWC influence mist condensation and water transport is revealed. The effects of height, angle, and frequency of condensate droplets on power generation performance are also systematically investigated. Remarkably, BFWC achieved a fog collection efficiency of 48940 mg cm⁻² h⁻¹, a 305% improvement over the non-bionic samples. Meanwhile, the transfer charge is quantified at 28.9 nC, demonstrating that BDFD can efficiently convert the mechanical energy of the condensed droplet into electrical energy. Therefore, this bionic strategy enhances the efficiency of the atmospheric fog energy utilization apparatus and offers prospects for mitigating deficiencies in freshwater and power resources.