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Solar-driven interfacial evaporation has shown great promise for desalination due to its high photothermal conversion efficiency. However, for interfacial evaporation, the evaporator must have superior mechanical quality and strong thermal stability. To this end, ceramic nanofibrous mats with good mechanical strength can serve as a stable substrate for desalination. Herein, with the aid of finite element analysis, flexible Al2O3/TiO2 nanofibrous mats with robust mechanical properties are fabricated, where the stress dispersion greatly facilitates the Al2O3/TiO2 nanospheres to be uniformly dispersed into the mat. The flexible nanofibrous mats exhibit a high tensile strength up to 2.18 MPa. Afterward, a two-dimensional (2D) Al2O3/TiO2/MXene mat is constructed by a simple drop-casting method. Interestingly, the evaporation rate of the Al2O3/TiO2/MXene-2 mat reached 1.43 kg m−2 h−1, and the light-to-vapor energy conversion efficiency can reach 102% at a power density of 1.0 kW m−2. To measure the desalination efficiency, five ion concentrations in the collected water were found to be well below the safe salinity levels defined by standards set by the World Health Organization and U.S Environmental Protection Agency. Utilizing basic origami technology, the three-dimensional (3D) photothermal evaporator was integrated with the 2D mat due to its flexibility and ductility. Additionally, the evaporation rate increased to 1.61 kg m−2 h−1. This study is critical in the design of composite ceramic nanofiber materials with high flexibility and photothermal conversion efficiency for multifunctional desalination. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) nanomaterials are critical to producing clean oxygenation or value-added chemical production by utilizing sustainable solar energy, but are always limited by simultaneous integration of architectural engineering and electronic regulation in one structure. Directed by density functional theory (DFT) calculations and finite element analysis (FEA), the bio-inspired ivy-like Fe2O3 heterostructures with enriched oxygen defects on TiO2 nanofibers are designed for boosting PEC performances. Ivy-like Fe2O3 photo-sheets remarkably enhanced the light harvesting by multiple light-mater interactions. The oxygen vacancies on Fe2O3 photo-sheets could aid the photons catching and promote the reactivity at active sites. More importantly, demonstrated by a well-designed dynamic observation, the abundant tip-edges within ivy-like Fe2O3 photo-sheets enabled the surface of heterostructure with hydrophilic and aerophobic properties. The functionalized surface allowed the rapid desorption of produced bubbles and thus ensured a high density of unoccupied active sites for electrolyte accessing. Featured by these attributes, the Fe2O3@TiO2 nanofibers delivered an excellent photocurrent of 40.8 mA/mg, high donor density (1.2 × 1018 cm−3), and rapid oxygen production rate (1 mmol/(L·h)). This work demonstrates a new strategy on nano-structural design for enhancing light-harvesting and making a hydrophilic/aerophobic surface on low-dimensional oxide nanomaterial, holding great potential on designing high-performance PEC devices for producing survival source gas, carbon-neutral fuel, and valued-chemicals. [ABSTRACT FROM AUTHOR]

Up to now, the synthesis of non‐ligand‐capped 2D transition‐metal nanostructures remained big synthetic challenges. Herein, ultrathin and microporous AlOOH/Al2O3 nanosheets were topologically grown on the surface of TiO2‐based nanofibers by a water‐only hydrothermal strategy starting from electrospun Al2O3/TiO2 nanofibers. The TiO2 nanofibers lowered the surface energy for the sustained‐released aluminum species and thereby allowed them in situ hydrated to laminar AlOOH. The metastable AlOOH tended to dehydrate to Al2O3 simultaneously, leaving a well‐maintained 2D structure with sharp corners and steps, as well as enriched micropores. The nanosheets‐on‐nanofibers exhibited 2856–3370 mg/g of adsorption capacity toward RhB and an efficient removal efficiency over 70% at high throughput (30 mL/h). The promoted light‐harvesting by the perpendicularly attached nanosheets further endowed a significant photodegradation for RhB within 1 h. The presented green and facile approach toward the fabrication of 2D metal oxide nanostructures paves the way to a new variety of oxide nanomaterials. [ABSTRACT FROM AUTHOR]