Effect of supports on activity and stability of Pt–Pd catalysts for oxygen reduction reaction in proton exchange membrane fuel cells

Abstract

The platinum-palladium alloy (Pt-Pd) catalysts were prepared on various supports including Vulcan XC72, Hicon Black (HB), multiwalled carbon nanotubes (MWCNTs), and titanium dioxide (TiO 2 ) by a combined approach of impregnation and seeding using NaBH 4 reduction at low temperature. Their oxygen reduction reaction (ORR) activities in single proton exchange membrane fuel cell (PEMFC) under a H 2 /O 2 environment and their stability in an acid electrolyte (0.5 M H 2 SO 4 ) were tested and compared with the Vulcan XC72-supported Pt (Pt/C) catalysts. The presence of the Pd metal as well as different types of supports affected the ORR activity in H 2 /O 2 environment and stability in the acid electrolyte. Overall, the HB-supported Pt-Pd (Pt-Pd/HB) catalysts provided the highest current density at 0.6 V under a H 2 /O 2 environment, while the MWCNT-supported Pt-Pd (PtPd/MWCNT) catalyst provided the best stability in an acid electrolyte.

Recent Development of Pd-Based Electrocatalysts for Proton Exchange Membrane Fuel Cells

“…Figure 9 shows a typical result of PdPt alloy for the ORR. The PdPt nanodendrites were two and a half times more active than the state-of-the-art Pt/C catalyst [253][254][255].…”

Electrochemical oxygen reduction behaviour of platinum nanoparticles supported on multi-walled carbon nanotube/titanium dioxide composites

“…A great deal of attention has been paid to metal oxides, in particular TiO 2 , SnO 2 , Nb x O y , WO 3 , MnO x , Ta 2 O 5 [7][8][9][10][11][12][13][14][15][16][17][18][19]. In recent years, intensive research has been focused on the investigation of TiO 2 as a potential candidate support material in the form of nanoparticles, nanotubes or combined with different carbon materials forming a multi-component composite support structure for catalytic nanoparticles [20][21][22][23][24][25][26][27][28][29]. Adding TiO 2 into the structure of high-area carbon support helps to achieve anticorrosion and anti-poisoning properties of electrocatalyst.…”

Fabrication of MEA based on sulfonic acid functionalized carbon supported platinum nanoparticles for oxygen reduction reaction in PEMFCs

“…increasing the catalyst stability [3][4][5] . For PEMFCs, electrode performance relies critically on the three phase boundary formations in the membrane-electrode-assembly (MEA) 6 .…”

“…Hydrophobic polytetrafluoroethylene (PTFE) is added into the gas diffusion layer to enhance water management, whereas Nafion ionomer is mixed with the catalyst later (CL) to improve the utilization of Pt catalyst. Electrochemical characterization has shown that the catalysts supported on functionalized carbons had a better performance for alcohol electro-oxidation [10][11][12][13] , formic acid electro-oxidation 14,15 , EG electro-oxidation 16 and oxygen reduction reaction 7,8,[17][18][19][20][21][22][23][24] as compared to unsulfonated counterparts. Besides, Nafion ionomer often affects the efficiency of the Pt catalyst by blocking the active sites thereby restricting the gas permeability of the catalyst layer as well as its electronic conductivity.…”

“…Recently CNTs, as innovative catalyst supports, have drawn a great deal of attention due to their unique surface structures, excellent mechanical and thermal properties, high electric conductivity, and large surface areas 22 . Much research has focused on the most commonly used carbon black supports, e.g.…”