Plasmonic silver nanoparticle-decorated electrospun nanofiber membrane for interfacial solar vapor generation

Abstract

Interfacial solar vapor generation as an emerging technique has great potential in solving water shortage and pollution problems. Electrospun nanofiber membrane with high porosity, mechanical flexibility, numerous microsized channels for fast water transport, and low thermal conductivity offers an ideal platform for solar vapor generation. In this research work, plasmonic silver nanoparticles (Ag NPs) were utilized as photothermal materials and electrospun polyacrylonitrile (PAN) nanofiber membranes as substrates to fabricate Ag nanoparticles-uniformly decorated PAN (Ag@PAN) nanofiber membranes by electroless plating method. The morphology and chemical composition of the membranes were characterized by field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffractometry. By varying the volume ratios of glucose and silver ammonia solution, the sizes of Ag NPs as well as the light-absorption ability of corresponding nanofiber membrane were regulated. As a result, the optimal Ag@PAN nanofiber membrane demonstrated a high light-absorption efficiency of 92.8% in the range of 280–2500 nm wavelength. The evaporation rate reached 1.34 kg m−2 h−1 and 5.83 kg m−2 h−1 under 1 sun and 5 sun irradiations, respectively. The plasmonic nanofiber membrane also exhibited long-term use stability, without any degradation in solar vapor generation performance even after 10 cycle tests. This work paves the way for the design and development of plasmonic nanofiber membranes as high-performance interfacial solar vapor generators.