Synthesis and Triethylamine Sensing Performance of Nanowires Assembled Leaf-like MoO3 Nanostructure

A multichip leaf-like MoO3 nanostructure assembled from one-dimensional nanowires has been synthesized by a simple solvothermal method using bis(acetylacetonato) dioxomolybdenum(VI) in a component solvent of acetic acid and deionized water at relatively lower temperature of 150 degrees C. The field emission scanning electron microscopic (FESEM) and transmission electron microscopy (TEM) observations indicate that the multichip MoO3 nanostructures are composed of a plurality of fine nanowires with rough surface. The X-ray powder diffraction (XRD), high-resolution transmission electron microscope (HRTEM) results signified that the MoO3 nanoleaves with the orthorhombic system, a distorted octahedral structure. And, the dominant exposed crystal plane of the leaf-like MoO3 was (021). In addition, the leaf-like MoO3 possessed distinctive selectivity, ultrahigh sensitivity and response time (similar to 5 s) towards 2.25 g.m(-3) triethylamine (TEA) at the operating temperature of 300 degrees C, even attained 12.4 at the low detection level (4.5 mg.m(-3)). Based on the analysis results, the growth and formation of crystalline phase was deemed to follow the oriented attachment mechanism. Accordingly, the enhanced sensing ability could be mainly ascribed to its unique nanostructure, linear combination of large density, and high specific surface area, which promote the substantial free diffusion of TEA gases into the blade hole, showing excellent response recovery.