Electrocatalytic activity of LiCo1-xFexO2 (0 ≤ x ≤ 1) for oxygen evolution reaction in alkaline medium

• Main Author: Tan, Cherynn Xue Ying
• Other Authors: Jason Xu Zhichuan
• Format: Final Year Project
• Language: English
• Published: 2016
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/66566
• Institution: Nanyang Technological University

With the drive towards becoming a hydrogen economy, the need for an efficient and affordable catalyst for the bottleneck oxygen evolution reaction (OER) in water splitting is critical. In this report, we present Li-based transition metal oxides as potential OER catalysts which have typically been used in Li-ion batteries but have recently gained interest. The OER activities of LiCoO2, LiFeO2 and the mixed LiCo1-xFexO2 synthesized by low temperature sol-gel method were investigated. Calcination temperature at 400 °C, 600 °C and 800 °C was first performed on LiCoO2 and LiFeO2 independently. Subsequently, choice temperature of 600 °C was used for the synthesis of mixed LiCo1-xFexO2 (x = 0, 0.25, 0.5, 0.75 and 1) in the investigation of the OER enhancing effect of Fe substitution. X-ray diffraction (XRD), cyclic voltammetry (CV) and Brunauer-Emmett-Teller (BET) measurements were taken to characterize and investigate the OER performance of the catalyst. Layered structured LiCo0.75Fe0.25O2 was determined to be the best performing OER catalyst with activities comparable to that of benchmarked IrO2. Its high OER activity are attributed to potential Co-Fe synergistic and surface modifications of Co atoms due to Fe doping.