Single-atom catalyst for high-performance methanol oxidation

Zhiqi Zhang,Francesco Ciucci,Yuhao Wang,Kai Wang,Meng Gu,Jian Wang,Qi Wang,Tianshou Zhao,Jongwoo Lim,Jiapeng Liu,Zheng Wang,Zhenghua Tang

doi:10.1038/s41467-021-25562-y

Abstract

Single-atom catalysts have been widely investigated for several electrocatalytic reactions except electrochemical alcohol oxidation. Herein, we synthesize atomically dispersed platinum on ruthenium oxide (Pt1/RuO2) using a simple impregnation-adsorption method. We find that Pt1/RuO2 has good electrocatalytic activity towards methanol oxidation in an alkaline media with a mass activity that is 15.3-times higher than that of commercial Pt/C (6766 vs. 441 mA mg‒1Pt). In contrast, single atom Pt on carbon black is inert. Further, the mass activity of Pt1/RuO2 is superior to that of most Pt-based catalysts previously developed. Moreover, Pt1/RuO2 has a high tolerance towards CO poisoning, resulting in excellent catalytic stability. Ab initio simulations and experiments reveal that the presence of Pt‒O3f (3-fold coordinatively bonded O)‒Rucus (coordinatively unsaturated Ru) bonds with the undercoordinated bridging O in Pt1/RuO2 favors the electrochemical dehydrogenation of methanol with lower energy barriers and onset potential than those encountered for Pt‒C and Pt‒Ru.

Highlights

Single-atom catalysts have been widely investigated for several electrocatalytic reactions except electrochemical alcohol oxidation
The methanol oxidation reaction (MOR) mechanism including the dehydrogenation of methanol and CO electrooxidation is further studied by density functional theory (DFT), confirming the experimental observation that the prepared SACs are active for the alcohol oxidation reaction
RuO2 and VXC-72 supports were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) (Supplementary Fig. 1)

Summary

Introduction

Single-atom catalysts have been widely investigated for several electrocatalytic reactions except electrochemical alcohol oxidation. The Pt1/RuO2 SACs showed superb mass activity (6766 mA mg‒1Pt) and stability towards the MOR, far superior to those of most Pt-based catalysts developed to date. The MOR mechanism including the dehydrogenation of methanol and CO electrooxidation is further studied by density functional theory (DFT), confirming the experimental observation that the prepared SACs are active for the alcohol oxidation reaction. This finding suggests an approach of SACs for direct alcohol fuel cells

Methods

Results

Conclusion