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Investigating CO2RR on diamond and doped diamond surfaces: Highlighting initial protonation's key role and the remarkable catalytic efficiency of BN surfaces. [Display omitted] • B, N co-doped diamonds boost CO2RR performance. • Key intermediates, OCHO* and COOH* critically influences C1 products. • The OCHO* key intermediates gives HCOOH whereas COOH* favors CH 2 O, CH 3 OH, and CH 4. • BN surfaces efficiently produce HCOOH production without applied overpotentials. • BN diamonds exhibited pronounced selectivity favor CO2RR over hydrogen evolution. We employed Periodic Density Functional Theory (DFT) to investigate the catalytic activity of single and double dopant of boron (B), nitrogen (N), and phosphorous (P) anchored on diamond surfaces for the CO 2 reduction reaction (CO2RR) by analyzing reaction energy profiles. Our findings show that the double-doped catalyst exhibits lower energy barriers in CO2RR compared to the single dopants. Specifically, when considering BB and NN configurations, there is a thermodynamic preference towards the formation of formic acid (HCOOH) with overpotentials of 0.40 and 0.09 V, respectively. The co-doped catalyst comprising B and N (BN) demonstrates a tendency towards the formation of HCOOH without requiring any applied overpotentials. Notably, BN outperforms other catalysts, occupying the top position on the volcano plot, indicating the lowest limiting potential (U L), remarkable thermal stability, and the ability to suppress the competing hydrogen evolution reaction (HER). This research provides valuable insights into the product differentiation in the electroreduction of CO 2. [ABSTRACT FROM AUTHOR]

• Combined experimental and DFT studies can elucidate the role of Pt catalyst. • Adding Pt atom into HY zeolite facilitates C‒C cleavage and formation processes. • The isomerization on Pt-HY catalyst required a remarkably low barrier of 0.97 eV. • The Pt-HY catalyst is more selective towards 2MP than 3MP. In this study, we used several in situ, and spectroscopy analyses to investigate the roles of platinum (Pt) in zeolite-supported Pt catalysts for selective n -alkane isomerization. HY zeolites were synthesized using the rice husk silica and impregnated with Pt precursor by incipient wetness impregnation. Typically, HY zeolites have proved to be active hydrocarbon cracking catalysts. The particular challenge is to find an effective catalyst, which favors the isomerization of n -alkanes without too much cracking. In this work, adding Pt atoms to HY zeolite provides an enhanced multifunctional catalyst for converting n -alkanes to branched hydrocarbons. To understand the effect of Pt, we further investigated the reaction mechanism of n -hexane isomerization to 2–methylpentane (2MP) and 3-methylpentane (3MP) by DFT simulations, using a cluster of 30T HY zeolite modeled through B3LYP + 3D calculations. We found that, at 450 °C, the isomerization on Pt-HY gives higher cracking products. Decreasing temperature to 300 °C yielded greater selectivity of branched hydrocarbons. In addition, DFT calculations demonstrate that the 2MP production via route A1 (C3-C4 bond activation) and a rate-determining step of 0.97 eV proved more thermodynamically and kinetically favorable than the 3MP product. This agrees well with our experimental observations. Consequently, the presence of Pt on the HY zeolite plays an essential role in both C C forming and breaking. Finally, the Pt–HY zeolite is an efficient catalyst for petroleum production, improving the octane number for catalytic performance and product selectivity by isomerizing straight-chain alkanes to their branched chain isomers. [ABSTRACT FROM AUTHOR]

• Our proposed pathway of CO 2 hydrogenation on required the significantly small energy barrier of 0.63 eV compared to graphene base catalyst. • The presence of CO 2 can help to facilitate hydrogen dissociation and hydrogenation reactions to produce the FA on the Pt-BV catalyst. • Hydrogen dissociation step an important role as rate determining step of CO 2 hydrogenation. • The carboxylate route is found to be more energetically and kinetically feasible rather than that it is formate route. In this work, we investigated the mechanism of CO 2 hydrogenation over the Pt-doped boron nitride nanosheets (Pt-BNNSs) by using the density functional theory (DFT). It is found that a Pt adatom can be effectively stabilized in boron vacancy site (Pt-BV). Our investigation shows that the reaction mechanisms of CO 2 hydrogenation over Pt-BV can be found in three possible reaction pathways: (i) co-adsorption, (ii) H 2 dissociation, and (iii) co-adsorption together with H 2 dissociation pathways. The co-adsorption together with H 2 dissociation provides the most favorable pathway among of these three proposed mechanisms. The important finding of our study is that the presence of CO 2 in step of hydrogen dissociation plays an important role in producing the FA on the Pt-BV catalyst. Moreover, we found that the hydrogenation of CO 2 via carboxylate (COOH) has the rate-determining step of 0.63 eV in the step of hydrogen dissociation. In addition, the microkinetic modelling suggests that the COOH route is found to be more energetically and kinetically feasible rather than that it is formate route (HCOO) with the reaction temperature at 350 K and pressure of 5 bar. Our calculation results provide an important information for developing Pt-BV catalysts and might shed light on experimental design the novel Pt-BV catalyst for the CO 2 hydrogenation and the conversion of greenhouse gases into value-added products. The presence of CO 2 can help to facilitate hydrogen dissociation and hydrogenation reactions to produce the FA on the Pt-BV catalyst. The rate determining step of formic acid decomposition is significantly lower (0.63 eV) compared to others graphene base catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Methane decomposition catalyzed by an Ru, Rh, or Pd atom supported on a carbon or boron nitride nanotubes was analyzed by means of the density functional theory with the M06-L hybrid functional. The results suggested that the dissociative reaction of methane was a single-step mechanism. Based on the calculated activation energy, the Ru-decorated carbon nanotube showed superior catalytic activity with an activation barrier of 14.5 kcal mol−1, followed by the Rh-decorated carbon nanotube (18.1 kcal mol−1) and the Pd-decorated carbon nanotube (25.6 kcal mol−1). The catalytic performances of metals supported on a boron nitride nanotube were better than those on a carbon nanotube. The total activation barrier for the Ru, Rh, and Pd atoms on boron nitride nanotube was 10.2, 14.0, and 20.5 kcal mol−1, respectively. Dissociative adsorption complexes on the Ru–boron nitride nanotube were the most stable. The anionic state of the supported metal atom was responsible for decreasing the activation energy of methane decomposition. Our finding provides a crucial point for further investigation. [ABSTRACT FROM AUTHOR]