Selective Deposition of Ru Nanoparticles on TiSi2 Nanonet and Its Utilization for Li2O2 Formation and Decomposition

• Published in: Journal of the American Chemical Society 2014-06, Vol.136 (25), p.8903-8906
• Main Authors: Xie, Jin, Yao, Xiahui, Madden, Ian P, Jiang, De-En, Chou, Lien-Yang, Tsung, Chia-Kuang, Wang, Dunwei
• Format: Article
• Language: English
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja504431k

The Li–O2 battery promises high capacity to meet the need for electrochemical energy storage applications. Successful development of the technology hinges on the availability of stable cathodes. The reactivity exhibited by a carbon support compromises the cyclability of Li–O2 operation. A noncarbon cathode support has therefore become a necessity. Using a TiSi2 nanonet as a high surface area, conductive support, we obtained a new noncarbon cathode material that corrects the deficiency. To enable oxygen reduction and evolution, Ru nanoparticles were deposited by atomic layer deposition onto TiSi2 nanonets. A surprising site-selective growth whereupon Ru nanoparticles only deposit onto the b planes of TiSi2 was observed. DFT calculations show that the selectivity is a result of different interface energetics. The resulting heteronanostructure proves to be a highly effective cathode material. It enables Li–O2 test cells that can be recharged more than 100 cycles with average round-trip efficiencies >70%.