Metal-organic framework derived porous carbon of light trapping structures for efficient solar steam generation

Abstract

Utilizing solar energy to evaporate water is a green and promising approach in addressing the issue of global freshwater shortage and water pollution. Carbon materials have gained extensive research attention as efficient solar absorbers for solar steam generation owing to the non-toxic nature and environmental friendliness. In this work, the metal-organic framework (MOF) derived porous carbon (MDPC) materials were first employed as solar absorbers for enhancing water evaporation. An efficient surface heating and evaporation system was designed by coating the leaf-like two-dimensional (2D) MOF precursor on stainless steel mesh followed by calcination (MDPC/SS mesh), and then in conjunction with a floating air-laid paper wrapped polyethylene (EPE) foam. The prepared solar evaporator with unique light trapping structures shows a high solar absorption (>97%), excellent hydrophilicity, and great surface heat localization for solar steam generation. Consequently, a photo-thermal conversion efficiency of 84.3% with an evaporation rate of 1.222 kg m−2 h−1 was achieved under one sun illumination. Furthermore, the MDPC/SS mesh shows good recyclability and durability. This work opens a new avenue for the application of MOF derived carbon as photo-thermal material in the field of solar steam generation.