Investigation of zeolitic imidazolate frameworks–derived carbon nanotubes thin film in solar vapor generation

Abstract

Solar vapor generation is considered a green and practical approach to take advantage of solar energy as a renewable source and provide pure water. However, developing suitable materials with high efficiency and long-term stability under one sun illumination is challenging. Consequently, in this paper, we manifested two-dimensional Zn/Co zeolitic imidazolate framework (ZIF)-L as a sacrificial template to prepare carbon nanotube (CNT) through carbonization of the ZIF-L (Z-CNT). This porous Z-CNT as the solar absorber was deposited on a low-cost fiber paper, as a carrier for water transport by the capillary effect. A polystyrene foam was placed under the provided film, which prevents the heat loss to bulk water. By utilizing this solar vapor generator, a high water evaporation rate of 1.44 kg m2 h−1 and a photothermal conversion efficiency of 84% was achieved under one sun. Beside the porosity, high light adsorption of carbon nano tubes (CNT) due to having black colour and low thermal conductivity of this material incorporate the high achieved efficiency.