Nanoflake-Engineered Zirconic Fibrous Aerogels with Parallel-Arrayed Conduits for Fast Nerve Agent Degradation.

Chemical warfare agents (CWAs) pose huge threats to ecological environments, agriculture, and human health due to the turbulent international situation in contemporary society. Zirconium hydroxide (Zr(OH)4) has captured the prime focus as an effective candidate for CWA decomposition but is often hindered by the isolated powder form. Here, we demonstrate a scalable three-dimensional space-confined synthetic strategy to fabricate nanoflake-engineered zirconic fibrous aerogels (NZFAs). Our strategy enables the stereoscopic Zr(OH)4 nanoflakes vertically and evenly in situ grown on the interconnected fibrous framework, remarkably enlarging the surface area and providing rich active sites for CWA catalysis. The as-synthesized NZFAs exhibit intriguing properties of ultralow density (>0.37 mg cm-3), shape-memory behavior under 90% strain, and robust fatigue resistance over 106 compression cycles at 40% strain. Meanwhile, the high air permeability, prominent adsorptivity, and reusability make them state-of-the-art chemical protective materials. This work may provide an avenue for developing next-generation aerogel-based catalysts and beyond.

Room-Temperature Ferromagnetic Ultrathin α-MoO3:Te Nanoflakes.

We materialized room-temperature ferromagnetism in ultrathin α-MoO3:Te nanoflakes. The α-MoO3:Te nanoflakes, which had been grown by vapor-phase epitaxy, clearly exhibited an Ag Raman band from symmetric stretching of υ(Mo-O3-Mo) in the 2D-like ultrathin α-MoO3:Te layer. Due to the intentional incorporation of smaller Te ions into bigger Mo sites, the pentacoordinated Mo5+ bonds were created inside the orthorhombic α-MoO3:Te lattice system. Since Mo5+ ions have magnetic moments from unpaired electron spins, a large number of overlapped bound magnetic polarons could be formed via ferromagnetic coupling with charged oxygen vacancies that are inevitably generated at pentacoordinated [Mo5+O5] centers. This gives rise to the increase in long-range ferromagnetic ordering and leads to room-temperature ferromagnetism in the entire α-MoO3:Te solid-state system. The results may move a step closer to the demonstration of spin functionalities in the wide bandgap semiconductor α-MoO3:Te.