Transition Metal Tungstate’s Electrocatalyst Supported on a Mixture of Reduced Graphene Oxide and Silica Template for Water Splitting

El-Khatib, Kamel M.; Amin, Rabab S.; Fetohi, Amani E.; Khater, Dena Z.

doi:10.21608/ejchem.2024.299575.9911

Transition Metal Tungstate’s Electrocatalyst Supported on a Mixture of Reduced Graphene Oxide and Silica Template for Water Splitting

Document Type : Original Article

Authors

National Research Centre

10.21608/ejchem.2024.299575.9911

Abstract

Development of efficient and cost-effective electrocatalysts for water splitting in alkaline medium is a critical issue. A series of nano-structured metal tungstate MWO4 (M = Co, Ni, Mn, Zn & Fe) is anchored on reduced graphene oxide and silica template via a one-pot hydrothermal method. The electrochemical performance of the electrocatalysts is evaluated for hydrogen and oxygen evolution reaction. All the electrocatalysts shows good performance in both reactions. MnWO4/rGO-ST/NF is the most efficient electrocatalyst for HER, at current densities of 10 and 50 mA cm−2, it requires overpotential values of 150 and 232 mV, respectively (Tafel slope 130 mV dec−1). In case of OER, Fe2(WO4)3/rGO-ST/NF has the best performance with overpotential values of 322, 339, and 352 mV at 10, 30, and 50 mA cm−2 respectively (Tafel slope 44 mV dec−1). MnWO₄/rGO-ST/NF||Fe₂(WO₄)₃/rGO-ST/NF electrode pair exhibits an exceptional 12-hour durability and cell voltage of 1.81 V for water splitting.

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