Rational Design of an Iridium-Tungsten Composite with an Iridium-Rich Surface for Acidic Water Oxidation

Gao，Jiajian1; Huang，Xiang2; Cai，Weizheng1; Wang，Qilun1; Jia，Chunmiao1; Liu，Bin1

2020-06-10

10.1021/acsami.0c05906

ACS Applied Materials & Interfaces   影响因子和分区

1944-8244

1944-8252

Developing highly active and stable water oxidation catalysts with reduced cost in acidic media plays a critical role in clean energy technologies such as fuel cells and electrolyzers. Precious iridium-based oxides are still the only oxygen evolution reaction (OER) catalysts with reasonable activity and stability in acid. Herein, we design iridium-tungsten composites with a metallic tungsten-rich core and an iridium-rich surface by the sol-gel method followed by hydrogen reduction. The thus obtained iridium-tungsten catalyst shows much higher intrinsic water oxidation activity (100 mA/mgIr at an overpotential of 290 mV) and stability (100 h at 10 mA/cm2geom) together with reduced iridium content (33 wt % only) as compared with pure iridium oxide. An operando method using H2O2 as a probe molecule is developed to determine the relative adsorption strength of the reaction intermediates (*OH and *OOH) in the OER process. Detailed characterization shows that the tungsten-incorporated surface not only modulates the adsorption energy of oxygen intermediates on iridium but also enhances the stability of iridium species in acid, while the metallic tungsten core exhibits high electrical conductivity, all of which collectively give rise to the much enhanced catalytic performance of iridium-tungsten composite in acidic water oxidation. A single-membrane electrode assembly is further prepared to demonstrate the advantages and potential application of iridium-tungsten composite in practical proton exchange membrane electrolyzers.

acidic water oxidation catalyst design core−shell structure electrocatalysis oxygen evolution reaction

SCI ; EI

英语

其他

Singapore Ministry of Education Academic Research Fund (AcRF) Tier 1[RG115/17][RG115/18] ; Singapore Ministry of Education Academic Research Fund (AcRF) Tier 2[MOE2016-T2-2-004]

Science & Technology - Other Topics ; Materials Science

Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary

WOS:000541679900048

AMER CHEMICAL SOC

20202708890729

Catalytic oxidation ; Iridium ; Oxygen ; Reaction intermediates ; Iridium compounds ; Sol-gel process ; Catalyst activity ; Sol-gels

Air Pollution Control:451.2 ; Precious Metals:547.1 ; Electrochemistry:801.4.1 ; Chemical Reactions:802.2 ; Chemical Agents and Basic Industrial Chemicals:803 ; Chemical Products Generally:804 ; Glass:812.3

2-s2.0-85086346712

Scopus

1.School of Chemical and Biomedical Engineering,Nanyang Technological University,62 Nanyang Drive,637459,Singapore
2.Department of Physics,Southern University of Science and Technology,No. 1088 Xueyuan Avenue,Shenzhen,Nanshan District,518055,China

Gao，Jiajian,Huang，Xiang,Cai，Weizheng,et al. Rational Design of an Iridium-Tungsten Composite with an Iridium-Rich Surface for Acidic Water Oxidation[J]. ACS Applied Materials & Interfaces,2020,12(23):25991-26001.

Gao，Jiajian,Huang，Xiang,Cai，Weizheng,Wang，Qilun,Jia，Chunmiao,&Liu，Bin.(2020).Rational Design of an Iridium-Tungsten Composite with an Iridium-Rich Surface for Acidic Water Oxidation.ACS Applied Materials & Interfaces,12(23),25991-26001.

Gao，Jiajian,et al."Rational Design of an Iridium-Tungsten Composite with an Iridium-Rich Surface for Acidic Water Oxidation".ACS Applied Materials & Interfaces 12.23(2020):25991-26001.