Laser-induced carbonization strategy for designing efficient dual-layer solar wastewater evaporator

Solar water evaporation technology is of great significance in alleviating the problem of clean water shortage. However, interface evaporation materials are crucial for solar evaporator and are hindered by high costs, complex processes, and environmental issues. In this work, a simple, fast, and environmentally friendly laser-induced carbonization strategy was used to convert commercial polypropylene into porous carbon materials in a one-step process, and assembled with natural bamboo to form an efficient dual-layer evaporator. The residual carbon nanotubes catalyst in the carbonized products further enhance its evaporation performance. The water evaporation rate of the evaporator under one sun is 1.93 kg·m−2·h−1. In addition, the evaporator has an evaporation rate of 1.62 to 1.85 kg·m−2·h−1 for wastewater containing methylene blue, carmine, CuCl2 and FeCl3. This strategy not only overcomes the limitations of traditional polymer carbonization methods but also allows for size adjustment based on the quantity of bamboo, and has been successfully applied to wastewater evaporation experiments under cold outdoor weather conditions. The proposed strategy not only elucidates the carbonization mechanism of polymers under laser irradiation, but also provides a new approach for the field of solar water evaporation.