Electrosprayed BiVO4 nanopillars coated with atomic-layer-deposited ZnO/TiO2 as highly efficient photoanodes for solar water splitting

Min Woo Kim, Karam Kim, Tae Yoon Ohm, Hyun Yoon, Bhavana Joshi, Edmund Samuel, Mark T. Swihart, Sung Kyu Choi, Hyunwoong Park, Suk Goo Yoon

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

We report the fabrication and the performance in photoelectrochemical water splitting of thin films of electrostatically sprayed nanotextured bismuth vanadate (BiVO4) pillars coated with thin ZnO/TiO2 passivation layers formed by atomic layer deposition. The thin ZnO and TiO2 layers deposited on the BiVO4 nanopillars formed a heterostructure that promoted electron–hole separation and the migration of electrons toward the ITO substrate. The photocurrent density (PCD) of the ZnO/TiO2 coated BiVO4 was 2.5 times higher (2.25 mA/cm2 at 1.2 V (versus Ag/AgCl)) than that of pristine BiVO4 (0.9 mA/cm2 at 1.2 V (versus Ag/AgCl)). We present incident/absorbed photon-to-current efficiency and electrochemical impedance measurements confirming that this improvement is a result of the heterojunction produced by the conformal ZnO/TiO2 coating and discuss the mechanism of this dramatic enhancement of PCD.

Original languageEnglish
Pages (from-to)721-729
Number of pages9
JournalChemical Engineering Journal
Volume333
DOIs
Publication statusPublished - 2018 Feb 1

Fingerprint

Photocurrents
Heterojunctions
Atomic layer deposition
Water
Bismuth
Passivation
Photons
bismuth
pillar
Fabrication
Thin films
Coatings
water
Electrons
coating
Substrates
substrate
electron
bismuth vanadium tetraoxide

Keywords

  • Atomic layer deposition
  • Bismuth vanadate nanopillar
  • Heterostructure
  • Photoanode
  • Photocurrent density
  • Water splitting

ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

Cite this

Electrosprayed BiVO4 nanopillars coated with atomic-layer-deposited ZnO/TiO2 as highly efficient photoanodes for solar water splitting. / Kim, Min Woo; Kim, Karam; Ohm, Tae Yoon; Yoon, Hyun; Joshi, Bhavana; Samuel, Edmund; Swihart, Mark T.; Choi, Sung Kyu; Park, Hyunwoong; Yoon, Suk Goo.

In: Chemical Engineering Journal, Vol. 333, 01.02.2018, p. 721-729.

Research output: Contribution to journalArticle

Kim, Min Woo ; Kim, Karam ; Ohm, Tae Yoon ; Yoon, Hyun ; Joshi, Bhavana ; Samuel, Edmund ; Swihart, Mark T. ; Choi, Sung Kyu ; Park, Hyunwoong ; Yoon, Suk Goo. / Electrosprayed BiVO4 nanopillars coated with atomic-layer-deposited ZnO/TiO2 as highly efficient photoanodes for solar water splitting. In: Chemical Engineering Journal. 2018 ; Vol. 333. pp. 721-729.
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AU - Samuel, Edmund

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