調節可能な構造を持つ単一のNiFe2O4の酸素進化反応の直接探査
Xiaoxi Lu1, Mingzhong Li2, Yu Peng1
1State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China.
Journal of the American Chemical Society
|October 6, 2021
まとめ
単一ナノ結晶の超グリッドの電気触媒活性を直接測定することが可能になった. この研究は,ニッケル酸化鉄と黄金の超粒子の大小と構成が酸素進化反応にどのように影響するかを明らかにしています.
科学分野:
- 材料科学
- 電気化学
- ナノテクノロジー
背景:
- 自己組み立てのナノクリスタル超グリッドは,触媒とエネルギーアプリケーションのために調整可能な特性を有しています.
- これらの材料の固有の電解活性を評価することは,アンサンブル平均化のために困難です.
研究 の 目的:
- 個々のナノ結晶の超グリッドの酸素進化反応 (OER) の活動を直接測定する.
- 調節可能なNiFe2O4とAuの超グリットにおける構造-活性関係を確立する.
主な方法:
- 単粒子レベルで直接の電気化学的測定を行うために,スキャニング電気化学細胞顕微鏡 (SECCM) を利用した.
- 相関構造分析のためにスキャニング電子顕微鏡 (SEM) を使った.
- 鉄酸化ニッケル (NiFe2O4) と金 (Au) のナノ結晶から成る研究されたスーパーグリット.
主要な成果:
- 単一のNiFe2O4超粒子の回転周波数 (TOF) は,1.92Vで0.2から11s^-1までの範囲である.
- 約800 nmより小さいNiFe2O4超粒子の大きさに依存する活動が観察された.
- Auナノ結晶を組み込むと,TOFが約6倍に増加し,アクティビティはより高いAu含有量で安定した.
結論:
- 個々のナノ結晶のスーパーラットで最初の単体電気化学の研究を実証した.
- 従来のアンサンブル測定では入手できない内在的な構造-活動関係.
- ナノ材料の電気触媒特性を特徴づけるための新しい方法論を提供した.
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