Highly pure water generation via solar driven evaporation and photodegradation based on laser-induced graphene

Abstract

Interfacial evaporation is one of the most environmentally friendly ways to obtain clean water. However, organic pollutants, especially volatile organic compounds (VOCs), can enter the vapor with solar drive and ultimately remain in the condensed water, significantly affecting the widespread application of solar-driven interfacial evaporation. In this study, a 3D interfacial evaporator, designed based on laser induced porous graphene and photocatalysts, has been developed to achieve high evaporation rates and excellent organic compound decomposition simultaneously, thereby obtaining clean water resources. The nano photocatalysts are introduced into porous graphene through hydrothermal and laser induced transfer technology. Due to the excellent photothermal performance of laser induced graphene and the 3D design of device, the solar driven evaporation efficiency of the interfacial evaporator can reach to 2.13 kg m⁻² h⁻¹ under 1.0 solar illumination. Moreover, thanks to the outstanding degradation performance of nano-TiO₂, the device can decompose more than 97 % of organic pollutants (Rhodamine B and Methylene Blue) under 90 min of 1 solar illumination. Furthermore, the decomposition efficiency can reach 99.8 % under 6 h of real solar radiation. Therefore, this device can sustainably provide clean water resources in an environmentally friendly manner, especially designed for economically challenged.