Leaf-like Tungsten Oxide Nanoplatelets Induced by Laser Ablation in Liquid and Subsequent Aging

A facile and chemically clean method, pulsed laser ablation in liquid medium (LAL), was utilized to produce precursor solutions, and leaf-like tungsten oxide (WO 3 ) nanoplatelets were synthesized after sequential aging treatment of precursors. In this work, the effects of aging temperature, aging time, and pH value of precursor solutions have been investigated. The well-defined leaf-like WO 3 nanoplatelets can only be achieved by aging the pristine precursor solutions at room temperature (25 °C) for 48 h. In particular, when the pH value of precursor solutions was decreased lower than 1.0, the obtained products were hierarchical quasi-spheres composed of several nanoplates. The preparation method reported here shows a novel synthetic approach to control and adjust the morphology and crystallite size of the prepared WO 3 nanomaterials, which has potential applications in gas sensing, electrochromic devices, and photocatalysis.