Strong Metal-Support Interaction Induced Fabrication Of Platinum-Based Catalysts For Efficient Hydrogen Production From Formic Acid And Methanol Solution

The depletion of fossil fuel is a major energy crisis that we have to face today,thus it is essential to develop environmental-friendly and renewable energy sources.Hydrogen(H2)is regarded as an ideal alternative for fossil energy because of its high energy density and clean combustion characteristics.However,the utilization of H2 is restricted by various factors,such as low hydrogen production rate and unstable hydrogen supply.Thus,efficient,stable and safe production of hydrogen becomes a key issue to the development of hydrogen energy.Formic acid(HCOOH)and methanol(CH3OH),two kinds of chemical hydrogen storage materials,are promising hydrogen storage materials because of their high hydrogen content.However,the low reactivity,high reaction temperature and poor stability of the catalyst in the dehydrogenation reactions limit their practical application.Previous studies have shown that the introduction of strong metal-support interaction(SMSI)is an effective way to improve the catalytic performance.To solve these problems,this thesis focuses on the development of catalysts with SMSI for the efficient and stable dehydrogenation of formic acid or methanol solution,and the catalytic reaction mechanism of the above reaction are also studied.The research scheme of this study is as follows:(1)For HCOOH dehydrogenation at low temperatures,high purity titanium borate(TiB2)was prepared by molten salt method,and Pt@TiB2 core-shell catalyst with SMSI was constructed.The SMSI effect between Pt nanoparticles and TiB2 leads to sintering-resistant Pt nanoparticles and allows electron transfer between Pt and TiB2,achieving efficient hydrogen production from HCOOH solution.Meanwhile,we found that H2O molecules can improve the catalytic performance via changing the configuration of HCOOH and accelerating the desorption of H-atom from HCOOH molecule.(2)For CH3OH reforming dehydrogenation,Pt/Mo2C catalyst with SMSI effect was synthesized for the efficient conversion of methanol and water into hydrogen and carbon dioxide.In this catalytic system,the synergistic effect between Pt and Mo2C is the key for efficient H2 generation via CH3OH reforming.The HR-TEM and XPS result demonstrated that Pt nanoparticles are partly encapsulated by Mo2C support,which accelerates the electron transfer and is conducive to the improvement of catalytic activity.In summary,this thesis reported that Pt-based catalyst with SMSI effect exhibit excellent catalytic performance for the dehydrogenation of formic acid or methanol solution,and the interface effect of metal/oxide has been successfully extended to metal/boron and metal/carbide catalytic systems.This new finding may provide a new strategy to design and develop highly stable supported Pt catalysts with outstanding activity and selectivity.