PHOTOELECTROCHEMICAL HYDROGEN PRODUCTION: FROM BASIC PRINCIPLES TO RECENT ADVANCES (Review article)

Population growth, economic and industrial development contribute to the growth of human energy consumption. The photoelectrochemical hydrogen production is one of the most environmentally friendly and costeffective technologies that can maintain the balance between the energy produced and consumption. Therefore, the study of materials in this direction and their improvement, increasing efficiency and stability, is an important scientific and technical task. Photoactive semiconductors (PS) absorb solar energy and convert it directly into chemical energy separating hydrogen and oxygen from water molecules. The article discusses the principle and mechanism of the photoelectrolysis process, the main requirements for materials, and the latest innovations in this direction. The water-splitting reaction, main parameters, and concepts are explained. Analyzing the latest results, the efficiency of converting sunlight into hydrogen was compared and analyzed. The main conclusion is that the  efficiency of the photoelectrochemical cells depends on the quality, complexity, and configuration of the materials.

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