Reconciling the experimental and computational methanol electro-oxidation activity via potential-dependent kinetic mechanism analysis

Liu，Haijun1,2,3; Sun，Fengman1,2,3; Chen，Ming2,3; Wang，Haijiang2,3

2022

10.1039/d2ta07190h

Journal of Materials Chemistry A   Impact Factor & Quartile

2050-7488

2050-7496

The kinetic mechanism of the methanol oxidation reaction (MOR) has been controversial due to the lack of accurate monitoring technology and static calculation of the kinetic process, as well as the failure to consider the relationship between the free energy barriers and electrode potential. This work focused on Pt and PtRu catalysts and assessed the potential-dependent MOR kinetic process via metal-electrolyte models to reconcile the experimental and computational MOR activity. The obtained results demonstrate that the potential-dependent rate-determining steps (RDSs) change with the increase of electrode potential in the orders of (R3: CHO* → CHO* + H + e) → (R5: CHO* → CO* + H + e) → (R14: CO* + OH* → CO* + H + e), and (R4: CHO* → CHO* + H + e) → (R5: CHO* → CO* + H + e) → (R14: CO* + OH* → CO* + H + e), respectively, which is attributed to the variation in the adsorption of intermediates and strength of the electrochemical double layer (E). Furthermore, the potential-dependent coverage of intermediates and degree of rate control (DRC) in the MOR kinetic process draw support from microkinetic modeling. The experimental cyclic voltammograms and theoretical computation are reconciled with max absolute differences (Δ) of 0.020 and 0.023 mA cm for Pt and PtRu, respectively, giving evidence for the nature of higher MOR activity for PtRu. Importantly, our explicitly dynamic approach elucidates the potential-dependent MOR kinetic process at both the molecular and atomic levels and paves the way for the complex multi-electron reaction kinetic simulation.

SCI

English

Corresponding

Ministry of Education Key Laboratory of Energy Conversion and Storage Technologies[Y01406010] ; Guangdong Innovative and Entrepreneurial Research Team Program[2016ZT06N500] ; Guangdong Provincial Key Laboratory of Energy Materials for Electric Power[2018B030322001]

Chemistry ; Energy & Fuels ; Materials Science

Chemistry, Physical ; Energy & Fuels ; Materials Science, Multidisciplinary

WOS:000874878700001

ROYAL SOC CHEMISTRY

2-s2.0-85141812912

Scopus

1.Harbin Institute of Technology,Harbin,150001,China
2.Department of Mechanical and Energy Engineering,Southern University of Science and Technology,Shenzhen,518055,China
3.Key Laboratory of Energy Conversion and Storage Technologies (Southern University of Science and Technology),Ministry of Education,Shenzhen,518055,China

Liu，Haijun,Sun，Fengman,Chen，Ming,et al. Reconciling the experimental and computational methanol electro-oxidation activity via potential-dependent kinetic mechanism analysis[J]. Journal of Materials Chemistry A,2022.

Liu，Haijun,Sun，Fengman,Chen，Ming,&Wang，Haijiang.(2022).Reconciling the experimental and computational methanol electro-oxidation activity via potential-dependent kinetic mechanism analysis.Journal of Materials Chemistry A.

Liu，Haijun,et al."Reconciling the experimental and computational methanol electro-oxidation activity via potential-dependent kinetic mechanism analysis".Journal of Materials Chemistry A (2022).