Fabrication of hollow VO2 microspheres by a facile template-free process

Abstract: In the work, we report a facile template-free approach to prepare hollow VO2 microspheres. Uniform hollow VO2 assemblies composed of ordered microspheres with an average diameter of 3.0µm and a hollow interior of 2.0µm were prepared by calcining the precursor, which was synthesized via heat preservation process sealed in Teflon-lined stainless autoclave in the presence of urea. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scan electron microscopy (SEM) have been used to characterize VO2 microspheres. The proposed mechanism for the formation of hollow VO2 microspheres is discussed. [Copyright &y& Elsevier]