제 목: Hydrogen diffusion in metallic structures and its application to hydrogen separation membranes

■ 연 사: 서진유 (한국과학기술연구원 수소에너지소재연구단 책임연구원)

■ 일 시: 2026년 03월 24일(화) 오후 4시             

■ 장 소: 응용공학동 1층 영상강의실 

■ 호 스 트: 신병하 교수님

■ Abstract : Hydrogen atoms can occupy interstitial sites within the crystal lattice of metals and may also preferentially reside at lattice defects. Once hydrogen penetrates into a metallic lattice, it can influence the mechanical stability of the material, sometimes causing degradation such as hydrogen embrittlement. At the same time, the unique mobility of hydrogen atoms in metallic lattices, significantly higher than that of most other small atoms, can be exploited for technological applications. In particular, certain metals can selectively allow hydrogen to permeate through their lattice structures while blocking other gases, making them promising candidates for hydrogen separation membranes used to extract hydrogen from mixed gas streams.

For such applications, several requirements must be satisfied simultaneously. The membrane material must maintain sufficient mechanical stability without suffering from hydrogen embrittlement, while also enabling efficient hydrogen transport through the metal. High hydrogen flux requires that hydrogen be absorbed into the metal and diffuse rapidly through the lattice. However, hydrogen absorption inevitably leads to lattice expansion, which can compromise the mechanical integrity of the membrane. Therefore, ideal membrane materials should exhibit a balanced combination of relatively low hydrogen solubility and high hydrogen diffusivity, enabling rapid hydrogen transport while minimizing structural degradation.

To design and evaluate such membrane materials, it is essential to quantify several key transport properties, including hydrogen solubility, hydrogen diffusivity, and hydrogen permeability, the latter being the product of solubility and diffusivity and directly related to hydrogen flux through the membrane.

In this seminar, the fundamental concepts of hydrogen transport in metals will be introduced, along with experimental approaches for evaluating hydrogen permeation properties. Several examples of membrane materials and their hydrogen transport characteristics will also be presented to illustrate how these principles can be applied in the development of hydrogen separation technologies.