Electro-Oxidation of Metal Oxide-Fabricated Graphitic Carbon Nitride for Hydrogen Production via Water Splitting

Coatings

Awais Ahmad¹  Ammar Mohamed Tighezza²  Abdullah A. Al-Kahtani²  Tayyaba Ashfaq³  Kiran Aftab³  Ifzan Arshad⁴  Shafaqat Ali⁵  Mariam Khan⁶ 

[1] Departamento de Quimica Organica, Universidad de Cordoba, Edificio Marie Curie (C-3), Ctra Nnal IV-A, Km 396, E14014 Cordoba, Spain;Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia;Department of Chemistry, Government College University, Faisalabad 38000, Pakistan;Department of Chemistry, University of Management and Technology, Sialkot Campus, Sialkot 51310, Pakistan;Department of Environmental Sciences and Engineering, Government College University, Allama Iqbal Road, Faisalabad 38000, Pakistan;School of Applied Sciences & Humanities (NUSASH), National University of Technology, Islamabad 44000, Pakistan;

关键词: hydrothermal;    cyclic voltammetry;    surface area;    electrochemical;    sensor;   

DOI  :  10.3390/coatings12050548

来源: DOAJ

【 摘 要 】

Hydrogen is a great sourcez of energy due to having zero emission of carbon-based contents. It is found primarily in water, which is abundant and renewable. For electrochemical splitting of water molecules, it is necessary to use catalytic materials that minimize energy consumption. As a famous carbon material, graphitic carbon nitride, with its excellent physicochemical properties and diversified functionalities, presents great potential in electrocatalytic sensing. In the present work, graphitic carbon nitride-fabricated metal tungstate nanocomposites are synthesized by the hydrothermal method to study their applications in catalysis, electrochemical sensing, and water splitting for hydrogen production. Nanocomposites using different metals, such as cobalt, manganese, strontium, tin, and nickel, were used as a precursor are synthesized via the hydrothermal process. The synthesized materials (g-C₃N₄/NiWO₄, g-C₃N₄/MnWO₄, g-C₃N₄/CoWO₄, g-C₃N₄/SnWO₄, g-C₃N₄/SrWO₄) were characterized using different techniques, such as FTIR and XRD. The presence of a functional groups between the metal and tungstate groups was confirmed by the FTIR spectra. All the nanocomposites show a tungstate peak at 600 cm⁻¹, while the vibrational absorption bands for metals appear in the range of 400–600 cm⁻¹. X-ray diffraction (XRD) shows that the characteristic peaks matched with the JCPDS in the literature, which confirmed the successful formation of all nanocomposites. The electrochemical active surface area is calculated by taking cyclic voltammograms of the potassium–ferrocyanide redox couple. Among the entire series of metal tungstate, the g-C₃N₄/NiWO₄ has a large surface area owing to the high conductive properties towards water oxidation. In order to study the electrocatalytic activity of the as-synthesized materials, electrochemical water splitting is performed by cyclic voltammetry in alkaline medium. All the synthesized materials proved to be efficient catalysts with enhanced conductive properties towards water oxidation. Among the entire series, g-C₃N₄-NiWO₄ is a very efficient electrocatalyst owing to its higher active surface area and conductive activity. The order of electrocatalytic sensing of the different composites is: g-C₃N₄-NiWO₄ > g-C₃N₄-SrWO₄ > g-C₃N₄-CoWO₄ > g-C₃N₄-SnWO₄ > g-C₃N₄-MnWO₄. Studies on electrochemically synthesized electrocatalysts revealed their catalytic activity, indicating their potential as electrode materials for direct hydrogen evolution for power generation.

【 授权许可】

Unknown