
Boosting the Photocurrent of the WO3/BiVO4 Heterojunction by Photoelectrodeposition of the Oxy-Hydroxide-Phosphates Based on Co, Fe, or Ni
Author(s) -
Dyovani Coelho,
João Pedro R. S. Gaudêncio,
Lúcia H. Mascaro
Publication year - 2022
Publication title -
journal of the brazilian chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.337
H-Index - 70
eISSN - 1678-4790
pISSN - 0103-5053
DOI - 10.21577/0103-5053.20220015
Subject(s) - photocurrent , heterojunction , materials science , chemical engineering , deposition (geology) , hydroxide , catalysis , metal , inorganic chemistry , chemistry , optoelectronics , metallurgy , organic chemistry , paleontology , sediment , engineering , biology
Here we investigated the photoelectrodeposition of oxygen-evolving catalysts (OECs) based on oxy-hydroxides-phosphates of Co, Fe, or Ni (CoPi, FePi, and NiPi) on the WO3/BiVO4 heterojunction and their activity in water oxidation. The OECs were deposited by cycles of (i) open-circuit potential (OCP) and (ii) applying a potential positive enough to oxidize the metallic precursor on the WO3/BiVO4. The crystalline and optical properties of the photoanodes were not significantly affected by the OECs deposition. However, there was a remarkable increase in the photocurrent densities (jpc) to water oxidation, where the modification with FePi showed the best result, achieving 2.12 mA cm−2, which corresponds to 2.83 times higher than the heterojunction without the OECs. Furthermore, the OECs deposition changed the morphology of the heterojunction with the deposition of a thin film on its surface. In addition, during the FePi deposition, the BiVO4 layer seems to partially dissolve. Our study shows a facile methodology to boost the activity of photoanodes to the water oxidation by photoelectrodeposition of OECs.