NiPd Supported on Mesostructured Silica Nanoparticle as Efficient Anode Electrocatalyst for Methanol Electrooxidation in Alkaline Media

Abstract

The direct methanol fuel cell (DMFC) is a portable device and has the potential to produce 10 times higher energy density than lithium-ion rechargeable batteries. It is essential to build efficient methanol electrooxidation reaction electrocatalysts for DMFCs to achieve their practical application in future energy storage and conversion. A catalyst consisting of nickel–palladium supported onto mesostructured silica nanoparticles (NiPd–MSN) was synthesized by the wet impregnation method, while MSN was synthesized using the sol-gel method. MSN act as a catalyst support and has very good characteristics for practical support due to its large surface area (>1000 m2/g) and good chemical and mechanical stability. The microstructure and catalytic activity of the electrocatalysts were analyzed by X-ray diffraction (XRD), Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), Brunauer–Emmet–Teller (BET) theory, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and chronoamperometry (CA). XRD showed that the NiPd–MSN electrocatalysts had a high crystallinity of PdO and NiO, while FESEM displayed that NiPd was dispersed homogeneously onto the high surface area of MSN. In alkaline media, the catalytic activity toward the methanol oxidation reaction (MOR) of NiPd–MSN demonstrated the highest, which was 657.03 mA mg−1 more than the other electrocatalysts. After 3600 s of CA analysis at −0.2 V (vs. Ag/AgCl), the MOR mass activity of NiPd–MSN in alkaline media was retained at a higher mass activity of 190.8 mA mg−1 while the other electrocatalyst was significantly lower than that. This electrocatalyst is a promising anode material toward MOR in alkaline media.

Bimetallic Pt or Pd-based carbon supported nanoparticles are more stable than their monometallic counterparts for application in membraneless alkaline fuel cell anodes

“…In conclusion, Pd-Ni/C is the best compromise between the materials' cost and the retention of ECSA and HOR activity in long-term operation; it is therefore the most-suitable material for use in AFC anodes. The recent literature confirms this finding, as whether used for methanol electrooxidation, ORR or HOR, both Pd and Ni component present excellent activity in high pH solution 22,24,[39][40][41] . Hence, combining them is surely beneficial for AFC reactions, not speaking from the lower cost of these materials versus purely PGM-based ones.…”

A Critical Assessment on Functional Attributes and Degradation Mechanism of Membrane Electrode Assembly Components in Direct Methanol Fuel Cells

“…Nickel-palladium supported onto mesostructured silica nanoparticles (NiPd-MSN) was used as an electrocatalyst for DMFC. The results of the study showed greater stability toward oxidation with 61% current retention and superior tolerance to the carbonaceous species accumulation compared with other electrocatalysts [185]. Poly(3,4-ethyl) (PEDOT) backed with carbon-supported Pt is used as anode catalysts for DMFC methanol oxidation which exhibits high mass activity and superior stability after 500 durability cycles, which is greater than those of commercial Pt/C catalyst [186].…”

Investigation of Pd2B- and NiB-Doped Pd–Ni/C Electrocatalysts with High Activity for Methanol Oxidation

“…It was found that the stability and activity of the Pd-based (Pd-M) alloy catalysts for the MOR, formed by adding a second type of metal, could be enhanced significantly. , They could be produced in various ways, such as the electrochemical reduction method, chemical reduction method, , wet impregnation method, and polyol technology method . In the chemical reduction method, NaBH 4 was generally used as a reducing agent. , For example, the PdM/RGO binary catalysts were synthesized using NaBH 4 by the chemical reduction method, in which polyethylene glycol (PEG) was used as a protective agent .…”