Enhanced CO tolerance of Pt clusters supported on graphene with lattice vacancies

Abstract

The adsorption of CO on Pt 4 clusters supported on graphene with lattice vacancies is studied theoretically using the first-principles calculation. Our results show that the electronic structure of the graphene-supported Pt 4 clusters is significantly modified by the interaction with carbon dangling bonds. As a result the adsorption energy of CO at a Pt site decreases almost linearly with the lowering of the Pt d-band center, in analogy with the linear law previously reported for CO adsorption on various Pt surfaces. An exceptional behavior is found for Pt 4 supported on graphene with a tetravacancy, where CO adsorption is noticeably weaker than predicted by the shift in the d-band center. Detailed electronic structure analyses reveal that the deviation from the linear scaling can be attributed to lack of Pt d states near the Fermi level that hybridize with CO molecular orbitals. The weakening of CO adsorption on the Pt 4 clusters is considered as a manifestation of the support effect of graphene, and leads to the enhancement of CO poisoning tolerance that is crucial for developing high-performance Pt cluster catalysts.

A comparative study on the stability of the furfural molecule on the low index Ni, Pd and Pt surfaces

“…All the calculations were performed using the PBE functional with Grimme's D3 dispersion correction and def-2-TZVP basis set. Further to this, partial density of states (PDOS) onto the molecular orbitals and density of states weighted by the crystal orbital overlap population (COOP) were calculated using the STATE package [ 46 – 50 ]. In the implementation of COOP in the STATE package, the wave functions of the adsorption system are expanded in terms of the molecular orbital of the Ff molecule and the substrate wave functions.…”

“…Open Sci. 9: 211516 molecular orbitals and density of states weighted by the crystal orbital overlap population (COOP) were calculated using the STATE package [46][47][48][49][50]. In the implementation of COOP in the STATE package, the wave functions of the adsorption system are expanded in terms of the molecular orbital of the Ff molecule and the substrate wave functions.…”

Adsorption of toxic gases on borophene: surface deformation links to chemisorptions

“…41 The work function is dened as f ¼ E vac À E F and was calculated with dipole correction, 42,43 where E vac and E F are the vacuum level and the Fermi energy, respectively. To understand the hybridization between the gas molecule and borophene orbitals, we performed the crystal orbital overlap population (COOP) [44][45][46] and the projected density of states (PDOS) analyses as implemented in the STATE (Simulation Tool for Atom Technology) code. 47,48 The change in molecular internal bonds of the adsorbed state is understood by using COOP analysis among atomic orbitals (AOs) implemented in the LOBSTER package.…”

Supportive activity of Pt nanoparticles on the nitrogen‐doped graphene nanosheet with vacancy defects for catalyzing neutral glucose oxidation

“…Theoretically, the electronic structure of a dGN-supported Pt catalyst can be significantly modified by the interaction of carbon dangling bonds. 3 The resulting shift of the d-band center of Pt on a tetravacancy leads to the weak adsorption ability of CO. 3 The point vacancy on the dGN support also improves the stability and CO tolerance of the Pt catalyst in the electrooxidation of methanol. 4 In addition, the doping of N into dGNs can increase the number of defects, enhancing the distribution of Pt 5 and Pt/Ni catalysts.…”

“…In the hydrogen evolution reaction, delocalized electrons on the vacancy defects change the local charge state of catalyst, 2 resulting in the optimization of the free energy of H atoms. Theoretically, the electronic structure of a dGN‐supported Pt catalyst can be significantly modified by the interaction of carbon dangling bonds. 3 The resulting shift of the d‐band center of Pt on a tetravacancy leads to the weak adsorption ability of CO 3 .…”