Synergistic Photothermal‐Photocatalytic Accordion‐Like Mo ₂ AlB ₂ MBene Membrane for High‐Efficiency Solar‐Powered Water Remediation

Abstract Addressing the global freshwater crisis demands advanced solutions where solar‐driven interfacial evaporation (SDIE) shows promise, yet integrated photothermal‐photocatalytic synergy within a single platform remains fundamentally challenging. An accordion‐like Mo ₂ AlB ₂ MBene is pioneered and engineered into a crosslinked MBene/Polyvinylachohol (PVA)/meso‐tetra (4‐carboxyphenyl) porphyrin (TCPP) composite membrane (MPTM) that synergistically unifies solar harvesting and catalytic degradation. This architecture leverages accordion‐like MBene nanosheets and interfacial porphyrin coordination to establish a dynamic hydrophilic network with exceptional broadband absorption (93.3% average, 200–2500 nm). Through Schottky junction formation and charge redistribution, the system achieves unprecedented solar evaporation rates (2.24 kg m ^{− 2} h ⁻¹ under 1 sun) while concurrently generating reactive oxygen species (•OH/•O ₂ ⁻ ) that degrade 98.7% organic pollutants (10 ppm rhodamine B) in 2 h. The MPTM sustains > 85% evaporation efficiency during long‐term stability operation (Bohai seawater, 200 h) with < 4% efficiency decay, establishing a new paradigm for solar‐powered water purification.