Ta2O5-incorporated in photoinduced electrocatalyst of TiO2-RuO2 decorated by PPy-NrGO nanocomposite for boosting overall water splitting

Haleh Rasouli; Mir Ghasem Hosseini; Mir Majid Hosseini

doi:10.1016/j.jcis.2020.08.028

Ta₂O₅-incorporated in photoinduced electrocatalyst of TiO₂-RuO₂ decorated by PPy-NrGO nanocomposite for boosting overall water splitting

J Colloid Interface Sci. 2021 Jan 15;582(Pt A):254-269. doi: 10.1016/j.jcis.2020.08.028. Epub 2020 Aug 9.

Authors

Haleh Rasouli¹, Mir Ghasem Hosseini², Mir Majid Hosseini¹

Affiliations

¹ Electrochemistry Research Laboratory, Department of Physical Chemistry, Chemistry Faculty, University of Tabriz, Tabriz, Iran.
² Electrochemistry Research Laboratory, Department of Physical Chemistry, Chemistry Faculty, University of Tabriz, Tabriz, Iran; Engineering Faculty, Department of Materials Science and Nanotechnology, Near East University, 99138 Nicosia, North Cyprus, Mersin 10, Turkey. Electronic address: mg-Hosseini@tabrizu.ac.ir.

PMID: 32823127
DOI: 10.1016/j.jcis.2020.08.028

Abstract

In the current work, the heterostructures highly PEC activity photoelectrodes composed of mixed metal oxides (TiO₂-RuO₂-Ta₂O₅ (TRT)), polypyrrole- N doped reduced graphene oxide (PPy-NrGO) were prepared by electrodeposition of PPy-NrGO films on the TRT- coated titanium (Ti) plates as substrates. The TRT coatings were deposited on Ti plates via the sol-gel technique. The effects of the Ta₂O₅ molar ratios were followed using physical and PEC measurements. Morphology studies showed that the surface structure of photoelectrodes alters remarkably by changing the Ta₂O₅ content in the mixture of metal oxides. TRT/PPy-NrGO photoelectrodes indicated to have a decreasing impact on the charge transfer resistance at the photoelectrode/electrolyte interfaces. The overall PEC water splitting performances of photoelectrodes were compared by measuring photocurrent density at 0 and 1.23 V vs. RHE, Tafel slopes, charge carrier density, stability, hydrogen evaluation reaction (HER) and oxygen evaluation reaction (OER) efficiencies. The highest HER (43.68% at -0.4 V) and OER (17.51% at 0.45 V) efficiencies were obtained in photoelectrodes comprising of 20 mol% Ta₂O₅ which possessed charge carrier density (5.9 × 10¹⁸) of about 1.7 times higher than that considered for TRT (0%)/PPy-NrGO with no Ta₂O₅ in the mixture of metal oxides.

Keywords: Overall PEC water splitting; PPy-NrGO films; Tantalum oxide; Titanium oxide.