Synthesis of Single-Crystalline Nanoplates by Spray Pyrolysis: A Metathesis Route to Bi2WO6

Here, a solid-state metathesis reaction has been coupled with ultrasonic spray pyrolysis (USP) for the first time, yielding single-crystalline Bi2WO6 nanoplates. USP typically produces polycrystalline spherical particles, but by selecting precursors that yield Bi2WO6 and non-transient byproducts (e.g., NaCl), particles that are both single-crystalline and shape-controlled are achieved. This unprecedented result is directly correlated to the metathesis route employed to synthesize Bi2WO6 and contrasts with the results obtained when conventional precursors are used, which yields Bi2WO6 microspheres. Both the Bi2WO6 nanoplates and microspheres were extensively characterized. This comparative analysis found that the samples also differ in their surface terminations and hydrophilicity. Significantly, the integration of metathesis chemistry into spray pyrolysis may be generally applicable to the synthesis of a range of compositionally complex solids as single-crystalline samples.