Abstract
Photochromic nanoparticles of zinc-silicon oxide were synthesized using plasma enhanced chemical vapor deposition. These particles turned black upon irradiating with ultraviolet light. We investigated this phenomenon using density functional theory calculations. Silicon inclusions create trap levels and oxygen defects that reduce the ionization potential of ZnO. This forms a quantum potential between ZnO and zinc-silicon oxide, and the excited electron is stable. Because oxygen defects also increase the bond overlap population between the zinc atoms in a ZnO crystal, they introduce further defects and help in the formation of quantum potentials. Growth of a perfect crystal of ZnO prevents the formation of oxygen defects, which is not desirable for photochromism.
Highlights
Photochromism (PC) is a general term used for the color change induced by photon energy, and almost all photochromic materials exhibit reversible changes in color due to a specific photon energy or thermal process.[1,2,3,4,5,6,7] they are expected to be used in sensors and fast optical shutters
Based on electron probe microanalyser (EPMA), X-ray diffraction (XRD), and Rietvelt analysis, we confirmed that ZnO and zinc-silicon oxide (ZSO) nanocrystals were synthesized, and the composition ratio of Zn/Si was 2 for the ZSO crystal
Ab initio calculations indicated that ZnO and ZSO nanoparticles formed a quantum potential
Summary
Photochromism (PC) is a general term used for the color change induced by photon energy, and almost all photochromic materials exhibit reversible changes in color due to a specific photon energy or thermal process.[1,2,3,4,5,6,7] they are expected to be used in sensors and fast optical shutters. Some researchers speculated that these electrochromic materials could be used in energy-storable solar cells.[32,33,34,35,36,37,38] Terakado et al.[39] reported an erasable photochromic bilayer metal oxide film of tin oxide and magnesium oxide. In their paper, they inferred absorption or scattering for electrochromic phenomenon. There is no clear understanding of the mechanism, especially reversible color change by thermal process Because they are crystals, unlike materials modified by organic molecules, it is hard to anticipate structural change.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
