Fibrous MXene Aerogels with Tunable Pore Structures for High-Efficiency Desalination of Contaminated Seawater

Abstract

The seawater desalination based on solar-driven interfacial evaporation has emerged as a promising technique to alleviate the global crisis on freshwater shortage. However, achieving high desalination performance on actual, oil-contaminated seawater remains a critical challenge, because the transport channels and evaporation interfaces of the current solar evaporators are easily blocked by the oil slicks, resulting in undermined evaporation rate and conversion efficiency. Herein, we propose a facile strategy for fabricating a modularized solar evaporator based on flexible MXene aerogels with arbitrarily tunable, highly ordered cellular/lamellar pore structures for high-efficiency oil interception and desalination. The core design is the creation of 1D fibrous MXenes with sufficiently large aspect ratios, whose superior flexibility and plentiful link forms lay the basis for controllable 3D assembly into more complicated pore structures. The cellular pore structure is responsible for effective contaminants rejection due to the multi-sieving effect achieved by the omnipresent, isotropic wall apertures together with underwater superhydrophobicity, while the lamellar pore structure is favorable for rapid evaporation due to the presence of continuous, large-area evaporation channels. The modularized solar evaporator delivers the best evaporation rate (1.48 kg m−2 h−1) and conversion efficiency (92.08%) among all MXene-based desalination materials on oil-contaminated seawater."Image missing"

Anisotropic MXene/Poly(vinyl alcohol) Composite Hydrogels with Vertically Oriented Channels and Modulated Surface Topography for Efficient Solar-Driven Water Evaporation and Purification

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Hierarchical CuO/ZnO Heterojunction with Improved Spectrum Absorption for Interfacial Solar Steam Generation

“…The excellent performance of ISSG chiefly depends on these critical criteria: (1) powerful light capture and photothermal conversion to get more heat energy, (2) optimized thermal transfer controls to minimize heat loss, (3) quick water transportation to replenish water loss, and (4) excellent steam escape. , In view of this, the light capture layer is the key factor for achieving an evaporation rate and efficient water purification. − Currently, various photothermal materials with powerful light capture across the solar spectrum have been widely reported, including plasma nanoparticles, − carbon-based materials, − functional biomass materials, − organic polymers, − organic frameworks, − transition metal nitrides − and semiconductors. − …”

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