The First-Principle Study On The Mechanism Of Cell And Catalytic Interface

As civilization progresses,people’s awareness of energy and environmental challenges is growing.Researchers have concentrated their efforts recently on developing clean and sustainable energy.China,a major energy-producing nation,proposed the objectives of"peak carbon dioxide emissions" and "carbon neutrality" in 2020.Thus,It is of great significance to develop electrochemical energy storage equipment and strive to reduce carbon content.First-principles theoretical simulation is crucial in the simulation of energy chemistry.In this paper,we use the first-principles method to study some important issues in energy.The first category of electrochemical issues is battery energy storage,namely the microstructure of the solid electrolyte interface and the chemical processes that take place in lithium metal batteries;the second type of electrochemical issue is one with energy conversion by electrocatalysis,such as when hydrogen peroxide is produced by catalyzing the oxygen reduction process with a SnO2 catalyst and propylene is produced by selective hydrogenation with a PdBi alloy catalyst.In the above research,the achievements are as follows:1.Metastable hexagonal SnO2 nanobelts used for electrosynthesis of hydrogen peroxide.Hydrogen peroxide is the ideal oxidant because of its potent oxidizability,which makes it useful for cleaning,treating sewage,and other processes.It also produces green,non-polluting byproducts.Traditional methods to producing hydrogen peroxide consume a lot of energy,require a lot of equipment and pollute the environment.Hence,scientists are working to develop a better alternate technique of making hydrogen peroxide.One of these processes has grown in popularity as a result of its simple reaction mechanism and low energy requirement:the electrochemical reduction of oxygen to produce hydrogen peroxide.The findings of the experiments demonstrate that the new phase,SnO2,enhances the selectivity for hydrogen peroxide.However,the exact mechanism of the response is still not known.As a result,we investigated the production mechanism of hydrogen peroxide in the presence of the new phase SnO2 catalyst using density functional theory.The elementary reaction’s Gibbs free energy was computed.The intermediate products in the production of hydrogen peroxide were*O2,*HOO,and*H2O2,and the reaction that followed*HOO was the key step in the entire reaction.The results of the study suggest that the new phase,SnO2,can enhance the production of hydrogen peroxide,which,along with the experimental findings,offers a fresh concept for the electrocatalytic production of hydrogen peroxide.2.A study on the impact of lithium nitrate on SEI in lithium metal batteries.The lithium metal battery is thought to have excellent development potential and will likely become a common energy storage device in the upcoming generation due to its high energy density.Unfortunately,the issues with lithium dendrite and dead lithium have severely hampered the use of lithium metal batteries in commercial settings.This study looked at how multi-salt electrolytes affected the performance of lithium metal batteries.The results of the experimental study demonstrate that the electrolyte enhances lithium metal battery performance.To gain a comprehensive understanding of the reaction mechanism in lithium metal batteries,the molecular dynamics method(HAIR)with ab initio and reaction force field is employed to investigate the evolution and reaction mechanism of solid electrolyte interphase(SEI)structure.The HAIR simulation results demonstrate that the intercalation and deintercalation ability of lithium ions in lithium metal can be enhanced by lithium nitrate,and the products generated by the decomposition of solvent and solute lithium salt can form SEI with superior performance.This enhancement has significantly improved the overall performance of lithium metal batteries.Moreover,the X-ray photoelectron spectroscopy(XPS)results are consistent with the experimental findings,thereby providing a strong theoretical basis for a profound understanding of the SEI formation process.3.The efficient utilization of petroleum resources has always been a focal point of interest for researchers.Propylene,an essential chemical raw material derived from secondary processing of petroleum,is currently in high demand due to the increasing need for downstream products.However,the production of propylene is typically accompanied by the formation of by-products,which necessitates the development of strategies to produce propylene without any accompanying by-products.One such method is the catalytic hydrogenation of alkyne to produce propylene.Experimental findings indicate that PdBi alloy catalysts exhibit remarkable selectivity for propylene production.To understand the reaction mechanism underlying this catalytic process,we conducted a thorough investigation using the density functional theory(DFT)method.Herein,we constructed a structural model of the PdBi alloy catalyst and calculated the Gibbs free energy of hydrogen atoms and propylene using the VASP software package.Our computational findings align with the experimental observations,providing a deeper insight into the properties of surface alloy catalysts.