Process-induced nanostructures on anatase single crystals via pulsed-pressure MOCVD

Rukmini Gorthy, Susan Krumdieck, Catherine Bishop

Research output: Contribution to journalArticle

1 Downloads (Pure)

Abstract

The recent global pandemic of COVID-19 highlights the urgent need for practical applications of anti-microbial coatings on touch-surfaces. Nanostructured TiO2 is a promising candidate for the passive reduction of transmission when applied to handles, push-plates and switches in hospitals. Here we report control of the nanostructure dimension of the mille-feuille crystal plates in anatase columnar crystals as a function of the coating thickness. This nanoplate thickness is key to achieving the large aspect ratio of surface area to migration path length. TiO2 solid coatings were prepared by pulsed-pressure metalorganic chemical vapor deposition (pp-MOCVD) under the same deposition temperature and mass flux, with thickness ranging from 1.3-16 μm, by varying the number of precursor pulses. SEM and STEM were used to measure the mille-feuille plate width which is believed to be a key functional nano-dimension for photocatalytic activity. Competitive growth produces a larger columnar crystal diameter with thickness. The question is if the nano-dimension also increases with columnar crystal size. We report that the nano-dimension increases with the film thickness, ranging from 17-42 nm. The results of this study can be used to design a coating which has co-optimized thickness for durability and nano-dimension for enhanced photocatalytic properties.

Original languageEnglish
Article number1668
JournalMaterials
Volume13
Issue number7
DOIs
Publication statusPublished - 3 Apr 2020

Keywords

  • Anatase single crystals
  • Competitive growth
  • Pp-MOCVD
  • Process-induced nanostructures

ASJC Scopus subject areas

  • Materials Science(all)

Fingerprint Dive into the research topics of 'Process-induced nanostructures on anatase single crystals via pulsed-pressure MOCVD'. Together they form a unique fingerprint.

  • Cite this