g‐C3N4/CeO2/Fe3O4 Ternary Composite as an Efficient Bifunctional Catalyst for Overall Water Splitting

• Published in: ChemCatChem 2018-12, Vol.10 (24), p.5587-5592
• Main Authors: Rashid, Jamshaid, Parveen, Nadia, Haq, Tanveer ul, Iqbal, Aneela, Talib, Shamraiz Hussain, Awan, Saif Ullah, Hussain, Naveed, Zaheer, Muhammad
• Format: Article
• Language: English
• Subjects: Benchmarks; Bi-functional Catalysts; Carbon nitride; Catalysis; Catalysts; Cerium oxides; Current density; Graphitic Carbon Nitride; Hydrogen Evolution Reaction; Hydrogen evolution reactions; Iron oxides; Overall Water Splitting; Oxygen Evolution Reaction; Oxygen evolution reactions; Water splitting
• ISSN: 1867-3880; 1867-3899
• DOI: 10.1002/cctc.201801597

We report the very first example of a catalyst based on a ternary composite of graphitic carbonitride (g‐C3N4), ceria (CeO2) and magnetite (Fe3O4) for overall water splitting in 1.0 M KOH. Synergy between the components due to electronic effects results in a highly efficient catalyst which catalyzes Oxygen Evolution Reaction (OER) and Hydrogen Evolution Reaction (HER) at substantially low overpotentials (400 mV and 310 mV respectively) to produce benchmark current density (10 mA cm−2). OER activity of the catalysts surpasses that of the benchmark RuO2 catalyst at higher current densities (≥50 mA cm−2). The composite catalyst is stable and shows a Faraday efficiency of 98 % for OER. Overall water splitting was achieved at an overpotential of 1.94 V which is substantially high at 1 wt % loading of active metal. All together for overall water splitting: Ternary composite of graphitic carbon nitride, ceria and magnetite is reported for the first time as a potential electrocatalyst for overall water splitting. Synergy between the components leads to an enhanced catalytic activity for both OER and HER. The stable composite catalyst electrolyses water at an overpotential of 1.94 V.