Theoretical investigation for the reaction of N2O with CO catalyzed by Pt-Graphene

Abstract

To find an efficient catalyst to catalytic conversion of hazardous gases maybe the important way for solving environmental problems. We performed the first-principles density functional theory (DFT) to investigate the CO oxidation by using N 2 O as an oxidizing agent over an Pt-Graphene catalyst. The results indicated that CO oxidation by N 2 O on Pt-Graphene may occur via two pathways: (1) Adsorption of N 2 O followed by CO and (2) Adsorption of CO followed by N 2 O. Although the CO was more likely to adsorb on the PtGraphene than N 2 O, but when the Pt site was first covered by the CO, the higher barrier energy (20.28 kcal/mol) would limit the reaction to react. However, the N 2 O molecule was first decomposed on the Pt-site yielding the N 2 and O-PtGraphene, which was an active species for the CO oxidation. Thus, control of the adsorbing molecules over Pt-Graphene might be a key factor for the activity of the catalyst, and this may open new avenues in searching for oxidation of CO at an economical cost.

Potential of Single Transition Metal Atom Embedded C2N as Efficient Catalysts for N2O Reduction: Theoretical Investigation

“…The above results demonstrated that the adsorption energy of N 2 O is higher than that of CO, and N 2 O is preferentially adsorbed on V/C 2 N and Mn/C 2 N surfaces. By comparison with previous catalysts, we found that the adsorption of CO on the Pt‐doped graphene [ 26 ] is stronger than that of N 2 O, meaning that the V/C 2 N and Mn/C 2 N catalysts in this paper may have higher selectivity (Table 2).…”

“…From Figure 5d,f there are powerful interaction areas between the adsorbed TM and O atoms, indicating that the electrons on the 3 d orbitals of the TM atom transfer to the π * orbitals of the adsorbed N 2 O, thereby promoting the decomposition of N 2 O molecule. Furthermore, as shown in Table 2, V/C 2 N and Mn/C 2 N show remarkable adsorption performance compared with the adsorption energies (−4.9 and −21.1 kcal mol −1 ) and electron transfer values (0.01 and −0.66 e) of N 2 O on Pt‐doped graphene [ 26 ] and Ge‐doped graphene. [ 71 ] For N 2 O adsorption, N‐end was also examined.…”

“…[18][19][20][21][22] Especially, these catalysts not only minimize the use of materials but generates more active sites due to the high proportion of metal atoms, thereby enhancing the catalytic performance. [23][24][25] For instance, metal-embedded graphene [21,22,[26][27][28] and graphenelike structures [29,30] were widely designed for N 2 O reduction due to their abundance and low cost. Perfect graphene suffers from weak surface interaction with transition metal atoms.…”

Direct oxidation of methane to methanol on Co embedded N-doped graphene: Comparing the role of N2O and O2 as oxidants

“…Amongst an increasing number of single-atoms, most have been focusing on supporting noble metal atoms like Pt or Pd on metal oxide or metal surfaces [14,15]. Dopants such as P [16], Si [17,18], Fe [19,20], Pt [21,22], Pd [23,24], Ni [25,26] substitute with carbon atoms in the graphene sheet and can significantly enhance the properties of graphene sheet. On the other hands, tailoring the graphene sheet by introducing defects [27,28] or heteroatoms (e.g., N, B, P) [29] into the structure of graphene sheet will speed up the catalytic reactions occurred on the surface [30,31] and modulate the electronic properties of the catalyst [32][33][34][35].…”

DFT Study of N2O Adsorption onto the Surface of M-Decorated Graphene Oxide (M = Mg, Cu or Ag)

“…Due to its large specific area, high electron mobility (>200,000 cm 2 ∙V −1 ∙s −1 ), high thermal conductivity (>4000 W∙m∙K −1 ) and good tensile strength, graphene has been widely used in the experimental and theoretical studies of the catalyst matrix. Many scholars have studied the catalytic decomposition of N 2 O on the surfaces of modified graphene in the last decades, and they discovered that adding Fe [24], Ga [25], Al [25,26], Se [27], Si [27,28,29], Pt [30] and ZnO [31] to modify graphene’s properties can be helpful to develop its catalytic effect upon the decomposition of N 2 O. Graphene oxide (GO) is a kind of graphene derivative, containing an oxygen functional group, which can be prepared by Hummers’ Method, and regarded as a substitute for graphene nanomaterials at low cost [32]. Lv et al [33] have explored the adsorbing and decomposing process of our N 2 O molecule on the surfaces of Al-decorated graphene oxide (Al–GO), and they reported that the physically-adsorbed N 2 O could be decomposed to the N 2 molecule and an O atom bonded on Al–GO exothermally (2.33 eV per N 2 O molecule), the energy barrier of which is 0.5 eV.…”