摘要：Professor Kazunari Domen at the Shinshu University and the University of Tokyo has pioneered materials and techniques for solar-driven water splitting using photocatalysts,a promising technology for contributing to the construction of a sustainable and carbon-neutral *** this paper,we summarize his groundbreaking contributions to photocatalytic water splitting and,more broadly,photocatalytic *** highlight various novel functional photocatalytic materials,including oxides,(oxy)nitrides,and oxysulfides,along with innovative techniques such as cocatalyst engineering and Z-scheme system construction developed by the Domen *** team has also pioneered readily accessible and cost-effective photo(electro)chemical device fabrication methods,such as the particle-transfer method and thin-film-transfer ***,their research has made significant contributions to understanding the(photo)catalytic mechanisms using advanced characterization *** with his research team,Professor Domen has set many milestones in the field of photocatalytic overall water splitting,notably demonstrating the first scalable and stable 100 m^(2)solar H_(2)production system using only water and *** work has revealed the potential for practical solar H2 production from water and sunlight,and highlighted the application of fundamental principles,combined with chemical and materials science tools,to design effective photocatalytic *** this review,we focus on his research and the foundational design principles that can inspire the development of efficient photocatalytic systems for water splitting and solar fuel *** building on his contributions,we anticipate a significant impact on addressing major global energy challenges.