Preparation Studies Of Noble Metal Complex And Carbon Supported Catalyst Via Room Temperature Glow Discharge Electron Reduction

To date,carbon supported Pt catalysts are still the most effective and widely used cathode catalyst in polymer electrolyte membrane fuel cell(PEMFC).However,due to their sluggish kinetics of the oxygen reduction reaction(ORR)at the cathode and the poor stability,some processes need to be applied to improve the activity and the stability.According to our previous works,the noble metal catalysts prepared by glow discharge plasma has high catalytic activity and stability.This is because after the plasma process,the the size of noble metal NPs could be controlled,and the interaction between these NPs and the support could be enhanced.In this paper,a serious of Pt based catalysts was prepared by the glow discharge plasma,with the additives of peptide or Pd element.The reason for high catalytic activity and stability was discussed comprehensively.The preparation of noble metal nanoparticles on the surface of anodic aluminum oxide(AAO)by the glow discharge plasma was discussed firstly.The Ag/AAO samples have unique optical properties and outstanding SERS characteristic.The Ag NPs on the surface of AAO exist in the form of aggregation,and the colour of Ag/AAO samples depends on the size of these aggregations,rather than on the size of the single Ag nanoparticle.This study indicates that,without the impact of the surfactant and the protective agent,the relationship between the properties and the morphology of nanoparticles could be studied more intrinsically and accurately by using the glow discharge plasma.This study gives a foundation for studying Pt based catalyst through glow discharge plasma.Then,Pt/C-E catalyst was synthesized by the glow discharge plasma,and the catalytic activity on ORR and the stability of Pt/C-E catalyst were also thoroughly studied.According to the results through the RDE technique,both the catalytic activity and the stability of Pt/C-E catalyst are better than that of the commercial Pt/C catalyst.The facet exposed of Pt NPs are mainly(111)site with few(200)site featuring.Due to the characteristics of the surface sites,the bonding energy of oxygen on the Pt NPs was significantly decreased,so that the catalytic activity and the stability of Pt/C-E catalyst were increased.When the biological agents are applied as additives during the synthesizing process of noble metal NPs,it is easy to control the size and the morphology of NPs.In our previous works,we had proved that the Pt-Peptide sample prepared by the plasma had the outstanding optical catalytic activity.In this paper,Pt(111)-P/C catalyst with high catalytic activity and stability was prepared by the glow discharge plasma with peptide KLVFF as additives.The size of Pt NPs in the catalyst is about only 2 nm regardless of the changing of the Pt loading.Besides,Such Pt NPs show surface site featuring predominately(111)facet.With such size and surface site,the bonding energy of oxygen on the Pt NPs is the weakest.On the other hand,as the peptide being added,N element was doping on the carbon support.As a result,the electron transfer of the catalyst was enhanced and the adsorption of oxygen was also increased.So that,the catalytic activity and stability of Pt(111)-P/C catalyst was high.The process to prepare Pt based bimetallic catalysts with adding Au or Pd element has been proved to be an effective approach to improve Pt/C catalyst.In this paper,PtPd/C catalyst was prepared through glow discharge plasma,and its characteristics and electrocatalytic activity were tested comprehensively.The characterization implied that PtPd alloy nanoparticles were formed with size being about 2.5 nm.The PtPd/C catalyst also showed outstanding electrocatalytic activity and stability.This is due to the low binding energy between OHads group and the surface of PtPd alloy,and the high O2 decomposition rate as the PtPd alloy nanoparticles featuring predominately(111)facet.