The Preparation And Electrochemical Performance Of Platinum-based Nanocatalysts

In recent years,researchers are looking for effective energy sources to meet increasing energy consumption and the deteriorating environmental problems.Hydrogen/alcohol fuel cells have received widespread attention due to their environmental friendliness and sustainability.It is well known that catalytic materials with high catalytic activity and stability play a key role in the catalytic reaction for fuel cells.Pt has excellent catalytic activity,but its high cost limits the development of Pt-based catalysts.Therefore,in this thesis,the synthesis of Pt-based catalysts with low loading and high catalytic activity was used as the research purpose.Through a series of investigations,x%Pt?Naf?CV and Ptx?PVA catalytic materials were synthesized and applied to hydrogen evolution reaction and alcohol oxidation reaction.With the aid of Nafion,x%Pt?Naf?CV electrocatalytic material was synthesized by continuous potential cycling method.By adjusting different ratios between Nafion and chloroplatinic acid solution,the content and size of Pt in the catalyst were controlled.The electrochemical test results show that the 0.8%Pt?Naf?CV catalyst has the best hydrogen evolution performance.The overpotential is 34 m V at 10 m A cm^-2,and it shows excellent stability and durability for HER.The excellent performance of the electrocatalyst is mainly due to the synergy between the sulfonate groups in Nafion and Pt,which results in the synthesized Pt nanoparticles having smaller size and uniform dispersion,exposing a large number of active sites,at the same time,the amount of Pt is also reduced and the load per unit area is only 0.0048 mg cm^?2.A one-step hydrothermal method was used to prepare the Pt_x?PVA catalysts by adjusting the concentrations of PVA and chloroplatinic acid solution.Electrochemical test results show that Pt_1.88?PVA has the best electrocatalytic hydrogen evolution performance,and the overpotential is 34 m V at 10 m A cm^?2.At the same time,Pt_x?PVA catalyst was tested for alcohol oxidation.The results showed that Pt_0.19?PVA catalyst performed the best mass activity for methanol oxidation(413.72 A g _Pt^?1),ethanol oxidation(221.77 A g _Pt^?1)and the strongest resistance CO poisoning performance.The excellent HER and alcohol oxidation performance of Pt_x?PVA catalyst mainly attributed to the synergistic effect between a large amount of?OH in PVA and Pt Cl₆^2?and metal Pt.Pt_x?PVA catalysts with different optimal performance samples for HER and AOR,showing that the content of Pt has an important effect on the electrocatalytic results.