Surfactant-Free and Microporous AlOOH/Al2O3 Nanosheets on TiO2-Based Nanofibers: A Sustained-Release Dominated Topotactic Transformation

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.

Automated summary

In this study, a green and facile approach was used to fabricate highly efficient adsorbent and photocatalyst with two-dimensional transition metal oxide nanostructures. Ultrathin and microporous AlOOH/Al2O3 nanosheets were topologically grown on the surface of TiO2-based nanofibers, leading to high adsorption capacity and significant photodegradation for RhB dye.