Oriented assembly of monomicelles in beam stream enabling bimodal mesoporous metal oxide nanofibers

The assembly of monomicelles along one-dimension (1D) to construct tubular or fibrous mesostructures is greatly desired but still challenging. Herein, we have demonstrated a facile strategy to synthesize 1D bimodal mesoporous metal oxides (e.g., WO 3 , WO 3 /Pd, WO 3 /PdCu, TiO 2 , and ZrO 2 ) nanofibers (NFs) through assembling the organic-inorganic composite monomicelles in a beam stream generated via an electrospinning technique. This facile and repeatable methodology relies on the preparation of copolymer@metal-complex monomicelles in an anisotropic solution and oriented assembly of them in the beam stream by the selective evaporation of solvent. WO 3 and its derivatives are chosen as the demo, which show a uniform continuous fibrous structure with dual mesopore sizes (∼4.0 and 7.6 nm) and large surface area (∼93.1 m 2 g −1 ). Benefitting from the unique textual structure, gas sensors made by Pd-decorated mesoporous WO 3 NFs display outstanding comprehensive sensing performance to ethylbenzene, including a high sensitivity (52.5), an ultralow detection limit (50 ppb), and fast response/recovery kinetics (11/16 s) as well as an outstanding selectivity, which render them promising for rapid environmental monitoring.