Interfacial growth of the optimal BiVO4 nanoparticles onto self-assembled WO3 nanoplates for efficient photoelectrochemical water splitting

Vijay S Kumbhar; Hyeonkwon Lee; Jaewon Lee; Kiyoung Lee

doi:10.1016/j.jcis.2019.09.037

Interfacial growth of the optimal BiVO₄ nanoparticles onto self-assembled WO₃ nanoplates for efficient photoelectrochemical water splitting

J Colloid Interface Sci. 2019 Dec 1:557:478-487. doi: 10.1016/j.jcis.2019.09.037. Epub 2019 Sep 11.

Authors

Vijay S Kumbhar¹, Hyeonkwon Lee¹, Jaewon Lee¹, Kiyoung Lee²

Affiliations

¹ School of Nano & Materials Science and Engineering, Kyungpook National University, 2559 Gyeongsang-daero, Sangju, Gyeongbuk, South Korea; Research Institute of Environmental Science & Technology, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, South Korea.
² School of Nano & Materials Science and Engineering, Kyungpook National University, 2559 Gyeongsang-daero, Sangju, Gyeongbuk, South Korea; Research Institute of Environmental Science & Technology, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, South Korea. Electronic address: kiyoung@knu.ac.kr.

PMID: 31541917
DOI: 10.1016/j.jcis.2019.09.037

Abstract

Photoelectrochemical water splitting is the most efficient green engineering approach to convert the sun light into hydrogen energy. The formation of high surface area core-shell heterojunction with enhanced light-harvesting efficiency, elevated charge separation, and transport are key parameters in achieving the ideal water splitting performance of the photoanode. Herein, we demonstrate a first green engineering interfacial growth of the BiVO₄ nanoparticles onto self-assembled WO₃ nanoplates forming WO₃/BiVO₄ core-shell heterojunction for efficient PEC water splitting performance. The three different WO₃ nanostructures (nanoplates, nanobricks, and stacked nanosheets) were self-assembled on fluorine doped tin oxide glass substrates via hydrothermal route at various pH (0.8-1.2) of the solutions. In comparison to nanobricks and stacked nanosheets, WO₃ nanoplates displayed considerably elevated photocurrent density. Moreover, a simple and low cost green approach of modified chemical bath deposition technique was established for the optimal decoration of a BiVO₄ nanoparticles on vertically aligned WO₃ nanoplates. The boosted photoelectrochemical current density of 1.7 mA cm^-2 at 1.23 V vs. reversible hydrogen electrode (RHE) under AM 1.5 G illumination was achieved for the WO₃/BiVO₄ heterojunction which can be attributed to a suitable band alignment for the efficient charge transfer from BiVO₄ to WO₃, increased light harvesting capability of outer BiVO₄ layer, and high charge transfer efficiency of WO₃ nanoplates.

Keywords: Core-shell; Green hydrogen; Low cost; Photoelectrochemical water oxidation; WO(3)/BiVO(4) heterojunction.