MoO3-Promoted Rh Catalysts for Syngas Conversion to Alcoholsの構造と性質の関係を理解する
Arun S Asundi1, Adam S Hoffman2, Pallavi Bothra1,3
1Department of Chemical Engineering , Stanford University , Stanford , California 94305 , United States.
Journal of the American Chemical Society
|November 15, 2019
まとめ
モリブデン三酸化物 (MoO3) 促進されたロジウム (Rh) ナノ粒子は新しい触媒構造を生み出します. この構造は,シンガスを高酸素化物に変換するための触媒性能を大幅に高め,反応速度を66倍に増加させます.
科学分野:
- カタリシス
- 材料科学
- 表面化学
背景:
- ロジウム (Rh) 基の触媒は,高酸素酸に直接変換するのに有効です.
- Rh酸化金属触媒の構造とプロモーターの役割を理解することは,性能を最適化するために極めて重要です.
研究 の 目的:
- MoO3-促進Rhナノ粒子の構造を調査する.
- より高い酸素酸生成のための触媒活性と選択性の強化におけるMoO3の役割を解明する.
主な方法:
- Rhナノ粒子の正確なMoO3改変のために,原子層堆積 (ALD) を使用した原子制御合成.
- 反応条件下で表面構造を決定するX線吸収スペクトロスコーピー (XAS)
- プロモーター-Rh相互作用と反応メカニズムを理解するための密度関数理論 (DFT) の計算.
主要な成果:
- モリブデン (Mo) がRh表面に置換される新しい触媒構造が形成された.
- Mo-置換されたRh表面は反応条件下でMo-OH種を示す.
- 循環頻度が66倍増加し,酸素酸塩の産出量が増加した.
結論:
- MoのRh表面への置換は,触媒性能の強化の鍵です.
- Rh表面のMo-OH種は,CO解離を促進し,メタノール合成経路を安定させます.
- Mo-OHサイトからの水素の溢出は,中間物の水素化を促進し,全体的な反応速度を高めます.
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