Commercially Available Activated Carbon Fiber Felt Enables Efficient Solar Steam Generation

Sun-driven steam generation is now possible and has the potential to help meet future energy needs. Current technologies often use solar condensers to increase solar irradiance. More recently, a technology for solar steam generation that uses heated surface water and low optical concentration is reported. In this work, a commercially available activated carbon fiber felt is used to generate steam efficiently under one sun illumination. The evaporation rate and solar conversion efficiency reach 1.22 kg m(-2) h(-1) and 79.4%, respectively. The local temperature of the evaporator with a floating activated carbon fiber felt reaches 48 degrees C. Apart from the high absorptivity (about 94%) of the material, the evaporation performance is enhanced thanks to the well developed pores for improved water supply and steam escape and the low thermal conductivity, which enables reduced bulk water temperature increase. This study helps to find a promising material for solar steam generation using a water evaporator that can be produced economically (similar to 6 $/m(2)) with long-term stability.