Synthesis and characterization of hierarchical Ti3C2Tx MXene/graphitic-carbon nitride/activated carbon@luffa sponge composite for enhanced water desalination

Abstract

In this study, advanced solar steam technologies are explored for their potential applications in seawater desalination and wastewater purification. We have developed a three-dimensional photothermal evaporator using MXene, luffa sponge (LS), graphitic-carbon nitride (GCN) and activated carbon (AC). The hierarchical Ti₃C₂T_x MXene/GCN/AC@LS composite photothermal evaporator exhibits superior thermostability, pH stability, and mechanical durability. The Ti₃C₂T_x MXene/GCN/AC@LS composite evaporator having a dimension of 1.25 cm displays excellent performance, leading to a high evaporation rate of 2.6 kg m⁻²h⁻¹ and a high solar-thermal conversion efficiency of 96 % under 1 sun illumination. This high efficiency is attributed to the good light absorption by the Ti₃C₂T_x MXene/GCN/AC@LS composite coupled with a better wetting through the internal microchannels of the LS, which envisages a faster water delivery and evaporation of water. The Ti₃C₂T_x MXene/GCN/AC@LS composite captures the residual heat from the sidewall surface as an additional source of energy.