Spatially Confined Assembly of Monodisperse Ruthenium Nanoclusters in a Hierarchically Ordered Carbon Electrode for Efficient Hydrogen Evolution. Issue 20 (14th April 2018)

• Record Type: Journal Article
• Authors: Wang, Zhong‐Li; Sun, Keju; Henzie, Joel; Hao, Xianfeng; Li, Cuiling; Takei, Toshiaki; Kang, Yong‐Mook; Yamauchi, Yusuke
• Is Part Of: Angewandte Chemie international edition. Volume 57:Issue 20(2018)
• Page Start: 5848
• Page End: 5852
• Publication Date: 2018-04-14
• Subjects: electrocatalysis -- integrated electrodes -- metal nanoclusters -- polyaniline -- ruthenium; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201801467
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The redox units of polyaniline (PAni) are used cooperatively, and in situ, to assemble ruthenium (Ru) nanoclusters in a hierarchically ordered carbon electrode. The oxidized quinonoid imine (QI) units in PAni bond Ru complex ions selectively, whereas reduced benzenoid amine (BA) units cannot. By electrochemically tuning the ratio of QI to BA, Ru complexes are spatially confined in the outer layer of hierarchical PAni frameworks. Carbonization of Ru‐PAni hybrids induces nucleation on the outer surface of the carbon support, generating nearly monodisperse Ru nanoclusters. The optimized catalyst has a low loading of approximately 2 wt % Ru, but exhibits a mass activity for the hydrogen evolution reaction that is about 6.8 times better than commercial 20 wt % Pt/C catalyst. Abstract : Nature‐inspired assembly : Spatially confining monodisperse Ru nanoclusters to the surface of an integrated carbon support, using a binary cooperative assembly strategy, exposes abundant active sites and enables efficient use of the precious metal. The optimized Ru@NC(−0.2) catalyst has a low 2 wt % loading of ruthenium but generates H2 with an ultrahigh mass activity that is 6.8 times greater than that of commercial Pt/C.