Mechanistic insights into NO‒H2 reaction over Pt/boron-doped graphene catalyst

Zhenhua Yao; Lei Li; Xuguang Liu; Kwun Nam Hui; Ling Shi; Furong Zhou; Maocong Hu; K S Hui

doi:10.1016/j.jhazmat.2020.124327

Mechanistic insights into NO‒H₂ reaction over Pt/boron-doped graphene catalyst

J Hazard Mater. 2021 Mar 15:406:124327. doi: 10.1016/j.jhazmat.2020.124327. Epub 2020 Oct 20.

Authors

Zhenhua Yao¹, Lei Li², Xuguang Liu³, Kwun Nam Hui⁴, Ling Shi¹, Furong Zhou¹, Maocong Hu⁵, K S Hui⁶

Affiliations

¹ Hubei Key Laboratory of Industrial Fume and Dust Pollution Control, and Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, Jianghan University, Wuhan 430056, China.
² Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology (EBEAM) of Chongqing, Yangtze Normal University, Chongqing 408100, China.
³ College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
⁴ Institute of Applied Physics and Materials Engineering (IAPME) University of Macau Avenida da Universidade, Taipa, Macau, China.
⁵ Hubei Key Laboratory of Industrial Fume and Dust Pollution Control, and Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, Jianghan University, Wuhan 430056, China. Electronic address: maocong.hu@jhun.edu.cn.
⁶ School of Engineering, University of East Anglia, Norwich NR4 7TJ, United Kingdom. Electronic address: k.hui@uea.ac.uk.

PMID: 33139106
DOI: 10.1016/j.jhazmat.2020.124327

Abstract

This work presents a systematical experimental and density functional theory (DFT) studies to reveal the mechanism of NO reduction by H₂ reaction over platinum nanoparticles (NPs) deposited on boron-doped graphene (denoted as Pt/BG) catalyst. Both characterizations and DFT calculations identified boron (in Pt/BG) as an additional NO adsorption site other than the widely recognized Pt NPs. Moreover, BG led to a decrease of Pt NPs size in Pt/BG, which facilitated hydrogen spillover. The mathematical and physical criteria of the Langmuir-Hinshelwood dual-site kinetic model over the Pt/BG were satisfied, indicating that adsorbed NO on boron (in Pt/BG) was further activated by H-spillover. On the other hand, Pt/graphene (Pt/Gr) demonstrated a typical Langmuir-Hinshelwood single-site mechanism where Pt NPs solely served as active sites for NO adsorption. This work helps understand NO-H₂ reaction over Pt/BG and Pt/Gr catalysts in a closely mechanistic view and provides new insights into roles of active sites for improving the design of catalysts for NO abatement.

Keywords: DFT study; Graphene-based catalysis; Kinetic modeling; Langmuir−Hinshelwood dual-site mechanism; NO abatement.