Design And Application Of Precious Metal Selenide Electrocatalyst

With thehe living standard of people enhanced,excessive consumption of fossil energy has brought about energy shortage,greenhouse effect,environmental pollution and many other environmental problems.Therefore,low-temperature alcohol fuel cells,hydrogen and other clean energy began to attract the attention of researchers.Alcohol fuel cell is an ideal device which can directly convert chemical energy into electric energy,which mainly consists of alcohol oxidation reaction（AOR）at the anode and oxygen reduce reaction（ORR）at the cathode.The slow kinetics of anodic alcohol oxidation is an important factor limiting the application of alcohol fuel cells.At present,the most effective catalysts for AOR are precious metals Pt and Pd,but these catalysts also have disadvantages such as high cost and poor resistance to CO poisoning.Therefore,for alcohol oxidation,it is an important research direction to develop Pt and Pd catalysts with high efficiency and stability and good resistance to CO poisoning.Hydrogen is a promising energy source with high energy density,zero emission and environmental friendliness.Water splitting is an effective technology to produce hydrogen,which has no harm to the environment in the preparation process,and is the most ideal hydrogen production technology at present.The Pt is the most effective electrocatalyst for HER,but its cost is high,reserve is low and stability is poor,which limit its commercial production.For HER,catalysts with high performance,high stability and low cost need to be developed.In this paper,by combining non-metal Se with precious metals,and directly using them to catalyze AOR and HER,the main research contents are as follows:（1）Study on Electrocatalytic Oxidation of Alcohols Using Se Supported Pt.Pt/Se catalyst was prepared by using oil bath method to support Pt on Se support.Physical characterization and electrochemical test were carried out to evaluate the catalytic capacity of alcohol oxidation in acid medium.The results show that the catalytic activity of Pt/Se for the oxidation of methanol and ethanol in acidic medium is much higher than that of commercial Pt/C.Through the analysis of Tafel slope,electrochemical impedance spectrum（EIS）,CO-strpping curve and chronoamperometry（CA）curve,Pt/Se showed faster kinetic mechanism and better resistance to CO toxicity and stability（2）Electrocatalytic oxidation of alcohols by Pd Se/Se.Pd Se nanoparticles were synthesized on the surface of Se support by microwave method,and Pd Se/Se catalyst was obtained.Its ability to catalyze electrooxidation of alcohols in alkaline media was discussed by physical characterization and electrochemical methods.Pd Se/Se showed high catalytic capacity for methanol and ethanol oxidation in alkaline medium.The experimental results also confirmed that the addition of Se effectively improved the anti-CO poisoning ability and stability of the catalyst.（3）The application of carbon nanotube supported Ru Se₂ electrocatalyst in hydrogen evolution reaction.The Ru Se₂/CNTs-T catalysts were synthesized by microwave reduction of ethylene glycol with Se and Ru anchoring on carbon nanotubes.The catalytic capacity of Ru Se₂/CNTs-T for hydrogen evolution reaction in acidic and alkaline media and the reason for its high activity were investigated by means of physical characterization and electrochemical test.Ru Se₂/CNTs-T showed excellent electrocatalysis activity in both two electrolytes.The Ru Se₂/CNTs-T catalyst displayed remarkable performance with low overpotentials of 48 m V and 66 m V at 10 m A cm~2 in alkaline and acidic media,respectively.Especially,the calcined Ru Se₂ crystals with good crystallinity were formed,which effectively improved the stability of the catalyst.