Enhancement of hydrogen generation by using photo-catalytic-electrode of titanium oxide formed on micro- and nano-protrusions

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K06780
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: Hiroshima Kokusai Gakuin University
• Principal Investigator: NAKASA Keijiro 広島国際学院大学, 工学部, 研究員 (80034370)
• Co-Investigator(Kenkyū-buntansha): 久保 隆 広島国際学院大学, 工学部, 講師 (60309622)
• Research Collaborator: YMAMOTO akihiro
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 光触媒電極 / 水素 / ナノ材料 / 酸化チタン / 突起物

Outline of Final Research Achievements

Argon ion sputter etching was applied to titanium and titanium alloys to form fine protrusions. These samples were heated in air or exposed in oxygen plasma to form titanium oxide on the protrusions. The photo-catalytic reaction was investigated on the protrusion samples in pure water and in 3 % saline water using a counter electrode of platinum plate under the irradiation of artificial sunlight. The titanium oxide formed on fine protrusions of the commercially pure titanium showed a little larger hydrogen generation current density than that of the flat specimen without protrusions, and showed much larger hydrogen current density under visible light irradiation. The reason will be attributed mainly to a higher visible light absorptance of fine protrusions than that of the flat surface.

Free Research Field

機能・構造材料

Academic Significance and Societal Importance of the Research Achievements

エネルギ・環境問題を解決するため、クリーンで枯渇しない太陽エネルギの利用が期待されているが、その手段の一つに、光触媒を用いた水からの水素の製造がある。本研究では、耐海水性に優れたチタン・チタン合金の上に、ミクロン・ナノサイズの酸化チタン微細突起物を形成した。実験の結果、それらの微細突起物は太陽光の大部分を吸収し、光触媒反応により水あるいは海水を水素と酸素に分離できること、とくに可視光領域での水素生成効率が高いことが明らかになった。