Research On The Catalytic Activity Modulation Of Noble Metal Nanoparticles As Anodic Electrocatalysts

Proton exchange membrane fuel cell?PEMFC?as an important energy in twenty-first century,reveals several promising characteristics of new energy fuel cell include high specific energy,quick start,environment friendly,easy to carry,etc.As a mobile power supply,it has broad prospects for development.Noble metal nanoparticles are widely used as catalysts in the fuel cell,mainly including palladium and platinum precious metals.However,these precious metals are not only expensive owing to limited resources,but also being prone to poisoning,resulting in the decayed commercial development of fuel cells.In order to reduce the content of Pt and Pd,as well as improve the utilization rate of catalyst,the noble metal content and particle size of the fuel cell catalyst were carefully investigated to further improve its electrocatalytic performance.It is a scientific subject worthy of deep research,and is also one of the keys to solve the large-scale commercial development of Pt based catalysts.The paper investigated the electrocatalytic activity improvement of the catalyst by optimize loading,supporting and additives way to explore the fuel cell anode catalyst with high performance and low cost,providing more accurate data and theoretical basis for the future commercialization of this new green energy technology.The noble metal anode catalyst was optimized by three strategies,and the effect on the catalytic performance toward organic small molecule electro-oxidation reaction was investigated.The main research is divided into the following three parts:?1?Using liquid phase co-reduction method,we have performed the preparation of carbon nanotubes supported Pd-Ag-Cu ternary catalysts via the control of Pd/Ag atomic as 1:1?previous studies have shown the best catalytic performance in this Pd/Ag ratio case?.Through varying the Cu elements,the exploration on the improvement effect and in-depth mechanism of the electrocatalytic activities of Pd-Ag-Cu catalysts for methanol,ethanol and formic acid oxidation reaction were carefully investigated.The results showed that the Pd25Ag25Cu50/CNTs catalyst has the highest electrocatalytic activity improvement in methanol,ethanol and formic acid oxidation process as compared with the other catalysts.Meanwhile,the stability is also the best.?2?In this chapter,we used a new carrier,simple Cu₃P-C hybrid supported strategy to improve platinum nanoparticles performance on methanol,ethanol,ethylene glycol and formic acid electrocatalytic oxidation.It was found that when the mass ratio of Cu₃ P and C in the hybrid carrier was modulated as 1:1,the electrocatalytic performance improvement of Pt/C-Cu₃P50% catalyst was the highest.It further confirmed the introduction of hybrid supported strategy to promote the catalytic activity of Pt catalyst.?3?Through adding additives Fe₂ P,we explored the influence of the content of Fe₂ P in different proportion on the catalytic properties of platinum catalyst.As compared with the Cu₃ P supporting,not only the content of Fe₂ P is less but also it depicts smaller particles,the effect of Fe₂ P content on the electrocatalytic activity of Pt was investigated for methanol,ethanol and formic acid electro-oxidation.At present,taking the phosphide as additives,the electrocatalytic performance of the anode catalyst for the fuel cell is obviously improved.The results showed that superior proportion of additives Fe₂ P content is ca.5%,and the Pt-Fe₂P?5%?hybrid catalyst in the process of small organic molecules oxidation such as methanol,ethanol and formic acid exhibits the best catalytic performance.