Bioinspired “Spindle Knot Effect” Integrated into Mixed-Matrix Nanofibrous Membranes for Highly Efficient Solar-to-Vapor Conversion
Hao Ren, Yuhao Xiao, Chang Yang, Qingquan Tang, Zhiyue Dong, Xin Cui, Hua Wang, Luoxin Wang, Jiang Gong
Abstract
The microstructure of photothermal interface materials for solar steam generation is crucial to simultaneously optimize the water transfer path and solar-to-vapor conversion efficiency; however, it remains a formidable challenge. Herein, bioinspired by the spindle knot structure of spider silk, spindle-knotted nanofibrous mixed-matrix membranes are facilely prepared and exhibit highly efficient solar-to-vapor conversion due to the “spindle knot effect” that results from the localized solar-to-thermal conversion at the spindle knots and water’s directional movement on the spindle knots’ surface. The as-prepared membrane achieves an evaporation rate of 2.41 kg m –2 h –1 with a conversion efficiency of 95.9% under 1 Sun and a maximum water production of 4.81 kg m –2 in 1 day. Besides, it can output a high electric power of 0.89 W m –2 to power small devices due to the Seebeck effect and exhibit strong ice removal performance. This work reports the bioinspired strategy for constructing multifunctional photothermal interface materials.