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Laser Synthesis of Iridium Nanospheres for Overall Water Splitting.

ABSTRACT: Engineering surface structure of catalysts is an efficient way towards high catalytic performance. Here, we report on the synthesis of regular iridium nanospheres (Ir NSs), with abundant atomic steps prepared by a laser ablation technique. Atomic steps, consisting of one-atom level covering the surface of such Ir NSs, were observed by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The prepared Ir NSs exhibited remarkably enhanced activity both for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in acidic medium. As a bifunctional catalyst for overall water splitting, they achieved a cell voltage of 1.535 V @ 10 mA/cm², which is much lower than that of Pt/C-Ir/C couple (1.630 V @ 10 mA/cm²).

SUBMITTER: Wang HB

PROVIDER: S-EPMC6766323 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Laser Synthesis of Iridium Nanospheres for Overall Water Splitting.

Wang Hai-Bin HB Wang Jia-Qi JQ Mintcheva Neli N Wang Min M Li Shuang S Mao Jing J Liu Hui H Dong Cun-Ku CK Kulinich Sergei A SA Du Xi-Wen XW

Materials (Basel, Switzerland) 20190918 18

Engineering surface structure of catalysts is an efficient way towards high catalytic performance. Here, we report on the synthesis of regular iridium nanospheres (Ir NSs), with abundant atomic steps prepared by a laser ablation technique. Atomic steps, consisting of one-atom level covering the surface of such Ir NSs, were observed by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM)<b>.</b> The prepared Ir NSs exhibited remarkably enhanced ...[more]

PMID: 31540464

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