Manipulation of Catalyst Structure for Molybdenum Trioxide by Chemical Etching

Abstract

AbstractChemical etching method has been frequently used in defect investigation for crystalline materials in solid-state chemistry / physics and fundamental materials research. Recently, we apply this technique into catalytic materials fabrication. In this work, crystalline catalysts of orthorhombic MoO 3 have been prepared via a vapor phase deposition method and their crystallographic structure has been affirmed by XRD and FTIR investigations. A chemical etching method has been developed for restructuring these thermally processed catalysts. Using a 0.1 M NaOH etchant, {001} and {100} plane areas of the catalysts can be significantly increased while surface steps, ledges, and terraces are created upon this etching. Moreover, alternate crystal plane combinations of either {100} and {010}, or the {001} and {010} are observed on crystal edges and rectangular etch pits in the basal planes {010}. Technological merits and the processing parameters of this new method have also been identified. Following the findings of the current work, it is believed that the chemically carved surface structures may be crucial for certain MoO 3-involving catalytic reactions.