Understanding the Role of Gold Nanoparticles in Enhancing the Catalytic Activity of Manganese Oxides in Water Oxidation Reactions1. (3rd October 2014)

• Record Type: Journal Article
• Authors: Kuo, Chung‐Hao; Li, Weikun; Pahalagedara, Lakshitha; El‐Sawy, Abdelhamid M.; Kriz, David; Genz, Nina; Guild, Curtis; Ressler, Thorsten; Suib, Steven L.; He, Jie
• Is Part Of: Angewandte Chemie. Volume 127:Number 8(2015)
• Page Start: 2375
• Page End: 2380
• Publication Date: 2014-10-03
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201407783
• Languages: English
• ISSNs: 0044-8249

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The Earth‐abundant and inexpensive manganese oxides (MnO_{<italic>x</italic>}) have emerged as an intriguing type of catalysts for the water oxidation reaction. However, the overall turnover frequencies of MnO_{<italic>x</italic>} catalysts are still much lower than that of nanostructured IrO₂ and RuO₂ catalysts. Herein, we demonstrate that doping MnO_{<italic>x</italic>} polymorphs with gold nanoparticles (AuNPs) can result in a strong enhancement of catalytic activity for the water oxidation reaction. It is observed that, for the first time, the catalytic activity of MnO_{<italic>x</italic>}/AuNPs catalysts correlates strongly with the initial valence of the Mn centers. By promoting the formation of Mn³⁺ species, a small amount of AuNPs (&lt;5 %) in α‐MnO₂/AuNP catalysts significantly improved the catalytic activity up to 8.2 times in the photochemical and 6 times in the electrochemical system, compared with the activity of pure α‐MnO₂.</p> </abstract>