Breaking Long-Range Order in Iridium Oxide by Alkali Ion for Efficient Water Oxidation

Gao, Jiajian1; Xu, Cong-Qjao2; Hung, Sung-Fu3; Liu, Wei4; Cai, Weizheng1; Zeng, Zhiping1; Jia, Chunmiao1; Chen, Hao Ming3; Xiao, Hai2; Li, Jun2,5; Huang, Yanqiang4; Liu, Bin1

2019-02-20

10.1021/jacs.8b11456

Journal of the American Chemical Society   影响因子和分区

0002-7863

Oxygen electrochemistry plays a critical role in clean energy technologies such as fuel cells and electrolyzers, but the oxygen evolution reaction (OER) severely restricts the efficiency of these devices due to its slow kinetics. Here, we show that via incorporation of lithium ion into iridium oxide, the thus obtained amorphous iridium oxide (Li-IrOx) demonstrates outstanding water oxidation activity with an OER current density of 10 mA/cm(2) at 270 mV overpotential for 10 h of continuous operation in acidic electrolyte. DFT calculations show that lithium incorporation into iridium oxide is able to lower the activation barrier for OER X-ray absorption characterizations indicate that both amorphous Li-IrOx and rutile IrO2 own similar [IrO6] octahedron units but have different [IrO6] octahedron connection modes. Oxidation of iridium to higher oxidation states along with shrinkage in the Ir-O bond was observed by in situ X-ray absorption spectroscopy on amorphous Li-IrOx, but not on rutile IrO2 under OER operando conditions. The much more "flexible" disordered [IrO6] octahedrons with higher oxidation states in amorphous Li-IrOx as compared to the periodically interconnected "rigid" [IrO6] octahedrons in crystalline IrO2 are able to act as more electrophilic centers and thus effectively promote the fast turnover of water oxidation.

SCI ; EI

英语

ESI高被引 ; NI期刊 ; ESI高被引 ; ESI高被引 ; ESI高被引

通讯

Singapore Ministry of Education Academic Research Fund (AcRF) Tier 2[MOE2016-T2-2-004]

Chemistry

Chemistry, Multidisciplinary

WOS:000459642000035

AMER CHEMICAL SOC

20191006589909

Electrolytes ; Fuel cells ; Lithium compounds ; Oxidation ; Oxide minerals ; Oxygen ; Reaction kinetics ; Titanium dioxide ; X ray absorption spectroscopy

Minerals:482.2 ; Fuel Cells:702.2 ; Chemical Reactions:802.2 ; Chemical Products Generally:804 ; Inorganic Compounds:804.2 ; Atomic and Molecular Physics:931.3

Web of Science

1.Nanyang Technol Univ, Sch Chem & Biomed Engn, 62 Nanyang Dr, Singapore 637459, Singapore
2.Tsinghua Univ, Dept Chem, Beijing 100084, Peoples R China
3.Natl Taiwan Univ, Dept Chem, Taipei 106, Taiwan
4.Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis, 457 Zhongshan Rd, Dalian 116023, Peoples R China
5.Southern Univ Sci & Technol, Dept Chem, Shenzhen 518055, Peoples R China

Gao, Jiajian,Xu, Cong-Qjao,Hung, Sung-Fu,et al. Breaking Long-Range Order in Iridium Oxide by Alkali Ion for Efficient Water Oxidation[J]. Journal of the American Chemical Society,2019,141(7):3014-3023.

Gao, Jiajian.,Xu, Cong-Qjao.,Hung, Sung-Fu.,Liu, Wei.,Cai, Weizheng.,...&Liu, Bin.(2019).Breaking Long-Range Order in Iridium Oxide by Alkali Ion for Efficient Water Oxidation.Journal of the American Chemical Society,141(7),3014-3023.

Gao, Jiajian,et al."Breaking Long-Range Order in Iridium Oxide by Alkali Ion for Efficient Water Oxidation".Journal of the American Chemical Society 141.7(2019):3014-3023.