Efficiency enhancement on the solar steam generation by wick materials with wrapped graphene nanoparticles

Abstract

Solar steam generation technology can utilize abundant and renewable solar energy for many applications. In this work, we proposed a solar steam generator using wick material with wrapped graphene nanoparticles, and the energy efficiency can reaches up to 80%. Instead of traditional smearing method, the chemical wrapping method was used to better adhere the graphene nanoparticles on the wick materials. Through the SEM morphological results, the graphene nanoparticles are shown to be evenly wrapped across the fibres of the wick material, which have better dispersity and stability. The evaporation rate, instantaneous energy efficiency and the absorptivity of three wick materials with/without nanoparticles under different conditions were compared and analyzed. Among the three different wick materials, the flannel cloth with dense fine hairs can provide three-dimensional contact area for wrapping graphene nanoparticles and thus contribute to better evaporation. Additionally, the influence of two different reduction methods and different concentrations of graphene oxide solution on the energy efficiency was also discussed. Our work offers a simple and effective way of using nanotechnology in practical application for solar steam generation.