High-performance Electrocatalysts Engineering towards Faster Oxygen Evolution Reaction

The oxygen evolution reaction (OER) is a critical step for a wide range of energy storage and conversion applications. During the four-electron reactions that constitute the OER, an electrocatalyst is used to decrease the overpotential for water splitting. Conventionally, both heterogeneous and homogenous materials are employed as OER catalysts, but both feature their own benefits and drawbacks. The advantage of homogeneous catalysts is their high utilization of atoms, but their poor stability has limited their performances. In contrast, outstanding stability and recyclability are the benefits of heterogeneous catalysts, but their surface areas are inadequate, resulting in low efficiency for atom utilization. Therefore, two-dimensional (2D) materials and nanosheets have been investigated as electrocatalysts. With high specific surface areas, these materials combine the benefits of both heterogeneous and homogeneous catalysts, which may provide excellent properties to achieve high performance towards the OER. In this thesis, M3GeTe2 (MGT), and Ni5.46GeSe2 (NGS) were each fabricated by a solid-state reaction, and the 2D MGT and NGS nanosheets (NS) were successfully acquired by using a liquid exfoliation reaction. 2D MGT and NGS NS were validated in the electrocatalytic oxygen evolution reaction to demonstrate their catalytic applicability, and the Ni3GeTe2 (NGT) was found to have exceptionally high oxygen evolution activity. The OER performance of MGT was evaluated as a promising novel material for energy-related applications.