Polar bear hair inspired 3D photothermal evaporator for efficient solar steam desalination and electricity generation

While solar steam generation for desalination and electricity production is a burgeoning field, traditional systems often face challenges with rapid heat loss and salt buildup. To address these issues, we introduce a biomimetic approach, inspired by the unique thermal properties of polar bear hair. Our study presents a photothermal 3D hierarchical hollow Ppy@CuO nanorod array system, featuring a dual-structured design: a cone-shaped 3D topological structure for improved light absorption and a hollow structure for enhanced thermal insulation. This innovative approach effectively maximizes solar energy capture and reduces thermal losses, particularly in marine environments. Our system exhibits outstanding performance in solar steam generation, achieving high water evaporation rates and maintaining stability and efficiency in high-salinity settings. Under one solar illumination at a 75° tilt angle, the Ppy@CuO-3 NAs demonstrated an evaporation rate of 3.3 kg m−2 h−1 and an energy efficiency of 97.5 %. Additionally, the synergistic effect of released Cu2+ and Ppy resulted in a 99.9 % antibacterial rate against E. coli and S. aureus. This significant advancement in simultaneous, effective seawater desalination and efficient evaporation-driven electricity generation marks a crucial step toward future sustainable resource utilization.