CO oxidation catalyzed by Pt-embedded graphene: a first-principles investigation

Abstract

We addressed the potential catalytic role of Pt-embedded graphene in CO oxidation by first-principles-based calculations. We showed that the combination of highly reactive Pt atoms and defects over graphene makes the Pt-embedded graphene a superior mono-dispersed atomic catalyst for CO oxidation. The binding energy of a single Pt atom onto monovacancy defects is up to -7.10 eV, which not only ensures the high stability of the embedded Pt atom, but also vigorously excludes the possibility of diffusion and aggregation of embedded Pt atoms. This strong interfacial interaction also tunes the energy level of Pt-d states for the activation of O2, and promotes the formation and dissociation of the peroxide-like intermediate. The catalytic cycle of CO oxidation is initiated through the Langmuir-Hinshelwood mechanism, with the formation of a peroxide-like intermediate by the coadsorbed CO and O2, by the dissociation of which the CO2 molecule and an adsorbed O atom are formed. Then, another gaseous CO will react with the remnant O atom and make the embedded Pt atom available for the subsequent reaction. The calculated energy barriers for the formation and dissociation of the peroxide-like intermediate are as low as 0.33 and 0.15 eV, respectively, while that for the regeneration of the embedded Pt atom is 0.46 eV, indicating the potential high catalytic performance of Pt-embedded graphene for low temperature CO oxidation.

Structure Determination of Au on Pt(111) Surface: LEED, STM and DFT Study

“…Density of states distributions of Pt(111) and Au/Pt(111) systems were calculated for seven (clean platinum) and eight (one gold monolayer on platinum) atomic layers, respectively. In the case of density of states for clean Pt(111) surface, our results are in very good agreement with previous theoretical studies [73,74,75,76,77]. Changes in the electronic properties of our Au/Pt(111) system, compared to Pt(111), are visible.…”

Pd1/BN as a promising single atom catalyst of CO oxidation: a dispersion-corrected density functional theory study

“…The graphene supported individual, isolated Fe 13 , Au 14 , Pt 15,16 and Cu 17 atoms present great activity and selectivity to the CO oxidation reaction. And the h-BN supported single atomic Au 11 , Ru 12 , Co 18 , Cu 19 , Pt 20 and Fe 21 promote the CO oxidation at the low temperature.…”

Adsorption behavior of Pt embedded on N‐doped graphene sheets toward NO and NH3 molecules

“…Firstly, the structure of the catalysts is analyzed, the corresponding adsorption height of the Pt atom, bond lengths of Pt‐C (platinum atom and carbon atoms around it) and Pt‐N (platinum atom and nitrogen atoms around it), transferred electrons of Pt atom and adsorption energies are summarized in Table . Xin Liu et al studied CO oxidation catalyzed by Pt‐embedded graphene catalysts and Shangguo Liu et al used Pt single atom on functionalized graphene support catalysts to study the activation of oxygen, thus we compared our calculations with their results and find that the calculated structural parameters such as bond length and charge transfer are basically consistent with theirs, which indicates that the calculation result in this work is reasonable and credible. Since the size of platinum atoms is larger than that of carbon atoms, when the Pt atoms are intended to be embedded on the surface of the graphene, it forms a certain distance from the plane of the graphene due to steric effect and the tension .…”

“…Xin Liu et al studied CO oxidation catalyzed by Pt‐embedded graphene catalysts and Shangguo Liu et al used Pt single atom on functionalized graphene support catalysts to study the activation of oxygen, thus we compared our calculations with their results and find that the calculated structural parameters such as bond length and charge transfer are basically consistent with theirs, which indicates that the calculation result in this work is reasonable and credible. Since the size of platinum atoms is larger than that of carbon atoms, when the Pt atoms are intended to be embedded on the surface of the graphene, it forms a certain distance from the plane of the graphene due to steric effect and the tension . The adsorption height of Pt atom increases by 1.58, 1.66, 1.68, 1.73 Å, respectively, for Pt/SV‐GN, Pt/1 N‐GN, Pt/2 N‐GN, and Pt/3 N‐GN.…”