低温活動を強化するために完全に分散Rhアンサンブル触媒
Hojin Jeong1, Geonhee Lee2, Beom-Sik Kim1
1Department of Chemical and Biomolecular Engineering , Korea Advanced Institute of Science and Technology , Daejeon 34141 , South Korea.
Journal of the American Chemical Society
|July 6, 2018
まとめ
研究者は,低温酸化反応における単原子触媒 (SAC) を上回る高分散ロジウム (Rh) 触媒を開発した. これらの触媒は 原子効率と活性が向上し 工業用途に不可欠です
科学分野:
- 異質な触媒
- 材料科学
- 表面化学
背景:
- 貴金属の触媒は不可欠ですが,コストが高く,その使用を最小限に抑えることが重要な目標です.
- 単原子触媒 (SAC) は最大原子効率を提供するが,特定の反応のためのアンサンブルサイトがない.
- 複数の隣接する金属原子を必要とする反応は,SACによって触媒化することはできません.
研究 の 目的:
- アンサンブルサイトを持つ高分散ロジウム (Rh) 触媒を開発する.
- SACと比較して新しいRh触媒の触媒性能を評価する.
- 触媒形成のメカニズムとその活動への影響を理解する.
主な方法:
- 25時間 750°CでRh/CeO2の2重分の水熱処理
- 触媒分散とRh原子集積状態の特徴化 (ENS 対 SAC).
- CO,C3H6,C3H8の低温酸化における触媒活性試験,同時に反応するものを含む.
主要な成果:
- 水熱処理後,非分離Rh原子 (ENS) でほぼ100%の分散を達成した.
- ENS触媒は,Rh SACとは異なり,C3H6とC3H8の酸化を効果的に触媒化した.
- ENS触媒は,同時にCO,C3H6およびC3H8を酸化する時の光オフ温度 (T20) がSACと比較して (100°C対180°CのCO酸化) は著しく低かった.
結論:
- 開発されたENS Rh触媒は,SACと比較して低温酸化活動が優れている.
- 水熱処理はRh原子の分離を容易にし,表面ヒドロキシル群による再集積を防ぐ.
- この完全に分散したENS触媒は,高原子効率と特定の反応のための強化された触媒性能を提供します.
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