As global energy and environment problems draw increasing attention, Japan has set a target of net zero greenhouse gas emissions by 2050. It has become even more important to promote the development of technology for fully utilizing hydrogen in the future, and also to explore fundamental science.However, since the foundational science related to hydrogen (hereinafter, hydrogen science) spans an extremely wide range of academic fields including engineering, chemistry, physics, and biology, sufficient opportunities have not been established for sharing cutting-edge trends and promoting joint research.
Against this kind of background, the “Hydrogenomics: Creation of Innovative Materials, Devices, and Reaction Processes Using Higher-Order Hydrogen Functions” project was established under a Grant-in-Aid for Scientific Research on Innovative Areas from the Ministry of Education, Culture, Sports, Science and Technology (FY2018 to FY2022). Through this framework, research has been promoted with the aim of creating the science for mastering the advanced use of hydrogen. We call this research area “hydrogenomics” (hydrogen + omics [system of learning]), and strive to promote joint research related to the diverse physical properties and functions of flexibly and continuously transformable hydrogen through cooperation between researchers in a wide range of academic fields including engineering, chemistry, physics, and biology. Practical, systematic joint research into hydrogen science that spans such as wide range of academic fields is unprecedented worldwide and this is the first such attempt.
This book summarizes the following to provide a practical guide for obtaining new directions and widely sharing the state of activities in this new academic field, hydrogenomics.
Chapter 1 “Diverse properties of hydrogen in materials” gives an overview of the “high densification ability of hydrogen”, which is related to many of energy functions; the “interfacial localizability of hydrogen”, which is important for enhancing electronic functions and mechanical properties; the “fast migration ability of hydrogen”, which includes short- and long-range migration phenomena and coupling with electrons related to new conceptual devices: and “high activation ability of hydrogen”, which is related to new material conversion processes.
In order to fully utilize hydrogen based on these properties, it is essential to also perform research into analyzing and predicting hydrogen, which is difficult to detect in materials, with higher accuracy than ever before. Chapter 2 “Advanced measurements and calculations for hydrogen in materials” introduces cutting-edge hydrogen measurements driven by new methods, and the latest hydrogen calculations for “seeing” invisible hydrogen.
Chapters 3 to 5 introduce some results related to fully utilizing hydrogen to explain the state of activities in “hydrogenomics”. Chapter 3 “Synthesizing new materials” explains the latest in high-pressure synthesis and thin-film synthesis technology, and then introduces hydride-ion conductors, hydrogen boride sheets, and other materials. Chapter 4 “Designing new devices” introduces new concepts for devices related to hydrogen and hydrides, such as hydride-based all-solid-state batteries, hydrogen-doped solar cells, rechargeable fuel cells, and proton-coupled electron transfer thermochemical cells. Furthermore, Chapter 5 “Providing new reaction processes and visualization technology” introduces new synthesis techniques for amino acids and ammonia, and new hydrogen visualization technologies using metal complexes.

[Translation and revision from the Japanese language edition: The Science of Fully Utilizing “Hydrogen” Hydrogenomics, Kyoritsu Shuppan Co., Ltd., 2022]