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Cp*イリジウム複合体の電気化学的活性化により,電極駆動による水酸化触媒を用いる

Julianne M Thomsen¹, Stafford W Sheehan, Sara M Hashmi

¹Department of Chemistry, Yale University , 225 Prospect Street, New Haven, Connecticut 06520, United States.

Journal of the American Chemical Society

|September 5, 2014

まとめ

この研究は,効率的な電極駆動水酸化のためのイリジウム複合体の電気化学的活性化を実証しています. 活性化された種は,均質な水酸化触媒 (WOC) として作用し,水分裂技術における実用的な応用を可能にします.

科学分野:

無機化学無機化学とは
電気化学電気化学について
カタリシスカタリシスカタリシス

背景:

安定したケラートリガンドを持つ有機金属イリジウム複合体は,均質な水酸化触媒 (WOC) の前駆体として知られています.
以前の研究では,主にWOCの活動を評価するために犠牲の化学酸化物質を使用しており,実用的なアプリケーションを制限していました.

研究の目的:

均質な WOC の前駆体としての Cp*Ir 複合体の電気化学的活性化を調査する.
溶液中の均質なイリジウム種によって触媒化された真の電極駆動水酸化を実証するために.
フォト電気化学アプリケーションにおけるこれらのWOCの実用性を評価する.

主な方法:

Cp*Ir複合体の電気化学的活性化.
電気化学的方法を用いた酸素進化活動の測定.
異質なイリジウム酸化物形成を排除するための分析.
化学的および電気化学的活性化経路の比較.

主要な成果:

Cp*Ir前駆体は,測定可能なO2進化活性を示さなかった.
酸化活性化により,高ファラダイク効率で電極駆動O2の進化を可能にする高度に活性な均質なWOCsが得られました.
異質なイリジウム酸化物形成は排除され,均質な触媒が確認されました.
活性化経路 (化学対電気化学) は似ています.

結論:

電気化学的活性化により,高活性な同質イリジウム WOCsへの有効な経路が提供されます.
この方法により,電極駆動による水酸化が可能になり,触媒の実用性を高めます.
この発見は,光駆動水分裂のための光電化学ダイアドの WOCs の使用を支持しています.

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