Hydrogen Evolution Reaction on 2D Heterostructures: From Material Design to Performance Enhancement

Abstract

The urgency to address environmental concerns and energy-related challenges necessitates the advancement of sustainable and renewable energy sources, as well as the enhancement of energy storage and conversion technologies. The integration of electrochemical water splitting with extensive renewable energy harvesting systems is currently being recognized as a highly promising approach in this thesis. Moreover, hydrogen, which is generally recognized for its superior mass-energy density compared to other fuels, is commonly regarded as the optimal and most environmentally friendly energy carrier. The successful implementation of water splitting relies heavily on the advancement of economically viable, exceptionally efficient, and durable catalysts for the hydrogen evolution reaction. In recent times, there has been a notable demonstration of exceptional electrocatalytic performance in both the hydrogen evolution reaction and the oxygen evolution reaction by heterostructured catalysts. These catalysts consist of electrochemically active materials combined with various functional additions. It is worth mentioning that a few of these heterostructures, which do not contain precious metals, have demonstrated levels of activity that are equivalent to catalysts that depend on precious metals. In this way, the new class of two-dimensional (2D) semiconductors, such as transition metal oxides and chalcogenides, has gotten a lot of attention because of their unique features and possible uses in energy gathering. Besides, developing low-cost and highly efficient electrocatalysts is closely related to establishing the composition, structure, activity relationships and fundamental understanding of catalytic mechanisms. Finding 2D materials that can generate high-value electrochemistry energy harvesting through electrochemical conversion technologies in the green and sustrainable energy systems has remained challenges. Density functional theory (DFT) is becoming an important computational tool that can help us understand the relationship between the electrochemical performances and physical/chemical properties of catalysts. Improvements in DFT have had a growing effect on materials research, both in terms of basic understanding and the creation of materials for future technologies. Therefore, the main goal of this thesis is using DFT and machine learning to find out new 2D materials can be used to improve current applications in energy havesting, especially hydrogen evolution reaction (HER) catalysts, and to explain how multilayer, dopings and interface effects can be used to tune these 2D materials. Moreover, an extensive investigation into piezoelectric Janus materials establishes the fundamental basis for the advancement of these novel materials with prospective applications in the field of piezo-photoelectrochemistry in the imminent future.