Preparationof Low Loadingpt Membrane Electrode Assembly Onproton Exchange Membrane Fuel Cells

Proton exchange membrane fuel cell(PEMFC)refers to a type of battery device making use of the fuel internal energy.Apart from its outstanding performance in high energy exchange efficiency and environmental protection,PEMFC enjoys promising prospects in applying to electric vehicles,submarines,and all kinds of portable power,for its convenient operation,activation under the room temperature and small size.Nowadays,the key technology of PEMFC has become basically mature,and some types of products has been into market,but PEMFC is facing with an utmost obstacle to achieve mass commercialization as for its highly costs and short endurance.Meanwhile,anode catalysts easily leads to poisoning,degrading its catalyst utilization ratio to increase its costs.For these reasons,it is highly relevant to find a brand-new anode catalytic with great anti-toxicity capability,higher Pt utilization rate and low cost,while produce a well-performed membrane electrode assembly(MEA).Tungsten carbide has been an ideal substitute for proplatinum catalyst,as for inexpensive price,wide source channels and outstanding physical properties(of hardness and high melting point),and electrochemical characteristics(excellent electrical conductivity,stability,and anti-CO toxicity abilities).The production of the high-activity WC catalyst to replace rare and dear Pt metal,has greatly practical significance and commercial values for PEMFC commercialization.Herein,we choose the WC catalyst to prepare membrane electrode assembly for the use of PEMFC.And detect its performance on the PEMFC to push its commercial application.In this paper,firstly,we choose commercial Pt/C as the catalyst to study theeffects of hot-pressing and activation for the MEA.To study and optimize its hot-pressing parameters(such as hot-pressing time,temperature,and pressure)and activation parameters(including activation pattern,temperature,and time),which have a huge impact on the MEA.Further more,we intrduced a novel spraying technology,ultrasonic sparying,to prepare the catalyst layer which is the most important part of MEA.After optimized the parameters of the ultrasonic sparying methode,such as height,flux and air pressure,we compared the difference among the ultrasonic sparying,sparying by air brush and brush coating by hand.The results showed that ultrasonic sparying methode have a better reproducibility and utilization rate,which make the catalyst showed a better performance on PEMFC.We also studied the effect of amout of Nafion and Pt for the MEA.Finally,thanks to the accumulation of lab on the platinum-substitute catalysts of DMFCs,we choose some catalysts of low cost,high electro-catalysis performance and high yield to study their performance on the MEA.One is WC with good morphology,one is WC/C with high BET surface,and the last one is WC/rGO.After loading with platinum nanoparticles,catalysts showed the excellent electro catalytic performance for the methanol.