Computational design of BC_(3)N_(2) based single atom catalyst for dramatic activation of inert CO_(2) and CH4 gasses into CH_(3)COOH with ultralow CH_(4) dissociation barrier

The production of CH_(3)COOH from CO_(2)and CH_(4) has stimulated much interest due to the high energy density of C2 species.Various kinds of catalysts have been developed while the high dissociation barrier of CH_(4) and low selectivity still hinders the efficiency of the reaction.We have herein proposed a novel catalyst with single metals loaded on 2D BC_(3)N_(2) substrate(M@2D-BC_(3)N_(2))based on density functional theory.Among numerous candidates,Pt@2D-BC_(3)N_(2) possesses the most favorable reactivity with an ultralow barrier of CH_(4) splitting(0.26 e V),which is due to the efficient capture ability of CH_(4) on Pt site.Besides,the selectivity for CH_(3)COOH is also very high,which mainly stems from the unique electronic properties of molecules and substrate:The degenerated states,including s,px,pyand pz,in CO_(2)reflects the existence of delocalizedπbonds between C and O.This can interact with states of Pt(s),Pt(pz),Pt(dxz),Pt(dyz),and Pt(z2)in Pt@2D-BC_(3)N_(2).The kinetics model also proves that our system can promote CH_(3)COOH production via simply increasing the temperature or the coverage of CH_(4) and CO_(2).Our results provide a reasonable illustration in clarifying mechanism and propose promising candidates with high reactivity for further study.

Turning the V site in V@2D-BC_(3)N_(2)complex to high curvature state for efficient CO_(2)electroreduction to hydrocarbons

Hydrocarbons are promising products for CO_(2)electroreduction(CRR)while is impeded by the low selectivity.Turning the curvature of the active site is an effective strategy to change the adsorption properties and further regulate the product distribution and reactivity.Herein,we have designed a novel V single atom catalyst(SAC)based on rolled two-dimensional(2D)BC_(3)N_(2)substrate with different curvatures.The results have demonstrated that increased curvature can enhance the adsorption strength of CRR intermediates,which follows different mechanisms for systems with low and high curvature.This character eventually leads to the deviation away from the scaling line between Ead[CO]∼Ead[COOH]based on transition metals for V@2D-BC_(3)N_(2)systems.3-3 system is screened as the optimal candidate for hydrocarbons production due to the enhanced binding ability of adsorbates,which can increase the reactivity for hydrocarbons production and hinder the production of H2 and HCOOH simultaneously.

Prediction of stable BC_(3)N_(2)monolayer from first-principles calculations:Stoichiometry,crystal structure,electronic and adsorption properties

In this paper,a novel BC_(3)N_(2)monolayer has been found with a graphene-like structure using the developed particle swarm optimization algorithm in combination with ab initio calculations.The predicted structure meets the thermodynamical,dynamical,and mechanical stability requirements.Interestingly,the BC_(3)N_(2)plane shows a metallic character.Importantly,BC_(3)N_(2)has an in-plane stiffness comparable to that of graphene.We have also investigated the adsorption characteristics of CO_(2)on pristine monolayer and Mo functionalized monolayer using density functional theory.Subsequently,electronic structures of the interacting systems(CO_(2)molecule and substrates)have been preliminarily explored.The results show that Mo/BC_(3)N_(2)has a stronger adsorption capacity towards CO_(2)comparing with the pristine one,which can provide a reference for the further study of the CO_(2)reduction mechanism on the transition metal-functionalized surface as well as the new catalyst’s design.