Development of an Innovative Electrosynthesis Method of Diamond from Carbon Dioxide at Atmospheric Pressure

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K19024
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 36:Inorganic materials chemistry, energy-related chemistry, and related fields
• Research Institution: Kyoto University
• Principal Investigator: Nohira Toshiuyuki 京都大学, エネルギー理工学研究所, 教授 (00303876)
• Project Period (FY): 2021-07-09 – 2023-03-31
• Keywords: ダイヤモンド / 二酸化炭素 / 電解合成 / 溶融塩

Outline of Final Research Achievements

While high-pressure, high-temperature synthesis and gas-phase synthesis are well known as conventional diamond synthesis methods, there are no reports of synthesis from atmospheric pressure liquids. In this study, molten salt at 700°C was used as the electrolyte, and carbon dioxide and water were introduced as raw materials, followed by electrolysis at atmospheric pressure. The obtained samples were analyzed by Raman spectroscopy, and it was confirmed that diamond was synthesized. This study demonstrated the possibility of producing diamond, the ultimate high-value-added substance, in the socially demanded carbon dioxide fixation technology.

Free Research Field

電気化学

Academic Significance and Societal Importance of the Research Achievements

常圧液体からのダイヤモンド合成はこれまで報告されておらず、学術的意義は極めて大きい。さらに、二酸化炭素を原料としたダイヤモンド直接合成も世界で初めての成果であり、こちらも学術的意義が極めて大きい。さらに、本成果は、カーボンニュートラル社会を実現するために社会的要請の高い二酸化炭素固定化技術において、ダイヤモンドという究極の高付加価値物質を生産する可能性を示した点でも、特筆すべきものである。