Self-Assembled Hydrophobic/Hydrophilic Porphyrin-Ti<sub>3</sub>C<sub>2</sub>T<i><sub>x</sub></i> MXene Janus Membrane for Dual-Functional Enabled Photothermal Desalination
Baoping Zhang, Qinfen Gu, Cheng Wang, Qili Gao, Jiaxin Guo, Pak Wai Wong, C.T. Liu, Alicia Kyoungjin An
Abstract
Photothermal desalination is a promising approach for seawater purification by harvesting solar energy. Titanium carbide (Ti3C2Tx MXene) membranes have been regarded as potential materials for photothermal desalination by virtue of their excellent light-to-heat conversion. However, achieving a well-balanced synergy between high evaporation rate and good salt resistance remains a significant challenge due to their limited solar absorption and inferior stability. Herein, we report a self-assembled flexible porphyrin-Ti3C2Tx MXene Janus membrane (Janus PMX membrane) for dual-functional enabled photothermal desalination. The self-assembly of porphyrin on MXene not only effectively creates a favorable hydrophobic surface but also simultaneously enables efficient solar utilization. The significant interactions and charge redistribution between MXene and porphyrin lead to a stable hydrophobic/hydrophilic Janus structure with synergistically enhanced photothermal conversion. As a result, the Janus PMX membrane demonstrates highly efficient water pumping, heat localization, vapor generation, and salt resistance during photothermal desalination. This work presents an effective and facile strategy toward advancing a well-performing MXene membrane for efficient seawater desalination.