Study on hydrogen absorption mechanisms in in-plane plastically deformed palladium film and application to hydrogen sensor

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04896
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 29030:Applied condensed matter physics-related
• Research Institution: Nippon Institute of Technology
• Principal Investigator: Kato Fumihito 日本工業大学, 基幹工学部, 教授 (70780170)
• Co-Investigator(Kenkyū-buntansha): 荻 博次 大阪大学, 大学院工学研究科, 教授 (90252626)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 水素吸蔵材料 / パラジウム / 膜質分析 / 水晶振動子センサー / 水素ガスセンサー

Outline of Final Research Achievements

The mechanism by which Pd films deposited with in-plane plastic deformation sputtering method improves hydrogen detection sensitivity and response speed compared to conventional Pd films was investigated through visualization in film quality analysis. In the surface analysis of Pd films, successful observations were made of protrusions, sharp ridges, and dislocations caused by slip. And, in cross-sectional analysis, numerous twins indicating crystal defects in the grains were successfully observed. When Pd films absorb hydrogen, these defects become hydride precipitation sites, allowing more hydrogen to be absorbed. It was revealed that by using the in-plane plastic deformation sputtering method, many defects were formed positively on both the inside and surface of the Pd film, which were one contributing factor to the improvement in hydrogen detection sensitivity and response speed.

Free Research Field

応用物理

Academic Significance and Societal Importance of the Research Achievements

水素吸蔵材料のPdに関する多くの研究が展開されてきた。これまでも、Pdバルク材に、塑性変形を与えることで、水素検出感度が向上することは報告されてきたが、水素吸蔵機構は、完全には明らかにされていない。本研究では、塑性変形を与えたPd薄膜の膜質分析を通じて、水素検出感度向上の一因を明らかにした。本成果は、Pdの水素吸蔵機構の理解の深化に貢献するものであり、学術的意義が高い。また、面内塑性変形スパッタリング法で成膜したPd薄膜が、一般的なPd薄膜と比べ、高感度・高速応答性能に優れ、水素センサーの感応膜に応用できることを立証しており、安全・安心な水素社会実現に貢献しうる社会的意義ある成果といえる。