Electrocatalysis of nanostructured materials

• Main Author: Haider, Ishraq
• Other Authors: Huang Yizhong
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Materials
• Online Access: http://hdl.handle.net/10356/76787
• Institution: Nanyang Technological University

With the use of ammonia and cobalt (II) acetate tetrahydrate, Co(CH₃CO₂)₂·4 H₂O, a simple method that is free from surfactants, was executed to synthesise Co3O4 nanoparticles, under atmospheric pressure. Two different solvents were used for synthesis, the first being solely deionised (DI) water and the second being an equal mixture of DI water and ethanol, to influence the particle size, along with differing heat treatment temperatures. The oxygen evolution reaction (OER) properties of four samples were studied to determine which was the ideal specimen to be used in water splitting. Results signified that samples synthesised in ethanol-based solution developed smaller particle sizes, whereas higher temperatures led to bigger particle sizes. All four samples show appreciable OER activity, with overpotentials in the range of 369 to 396 millivolts (mV) and Tafel gradients between 56 and 71 mV/dec. Sample B-250 having the smallest average particle size of 18.0 nanometres, demonstrated the best electrocatalytic performance for the OER due to a small Tafel slope (56.54 mV/dec) and least overpotentials (369 and 377 mV) at a current density of 10 mA/cm2.