Influence of Metal Oxides on Platinum Activity towards Methanol Oxidation in H₂SO₄ solution

Abstract

Pt-CeO2 /C, Pt-TiO2 /C, and Pt-ZrO2 /C electrocatalysts were prepared by using a modified microwave-assisted polyol process. Physical characterization was performed by using XRD, TEM, and EDX analyses. The incorporation of different metal oxides increased the dispersion degree of Pt nanoparticles and reduced their diameter to 2.50 and 2.33 nm when TiO2 and ZrO2 were introduced to Pt/C, respectively. The electrocatalytic activity of various electrocatalysts was examined towards methanol oxidation in H2 SO4 solution by using cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy. Among the studied composites, Pt-ZrO2 /C was selected to be a candidate electrocatalyst for better electrochemical performance in direct methanol fuel cells.

A Vanadium(V) Oxide Nanorod Promoted Platinum/Reduced Graphene Oxide Electrocatalyst for Alcohol Oxidation under Acidic Conditions

“…Recently, the activity of Pt electrocatalysts was improved by adding metal oxides, sulfides, carbides, and nitrides as promoters . Among them, metal‐oxide promoters are more efficient because they provide hydroxy sources for removal of carbonaceous species, such as adsorbed CO (CO ads ), at lower potentials . Also, metal oxides stabilize Pt crystallites and avoid their random growth and accumulation during device operation for longer times.…”

“…Also, metal oxides stabilize Pt crystallites and avoid their random growth and accumulation during device operation for longer times. So far, Ru, Ce, Ti, V, Nb, Mo, W, Zr, Sn, Mn, Fe, Ni, and Co oxides have been studied as promoters to Pt‐based catalysts for the electrooxidation of alcohols . Among these oxides, vanadium(V) oxide (V 2 O 5 ) is a promising material for the electrocatalytic oxidation of alcohols .…”

“…[3,4,[12][13][14][15][16][17][18][19] Among them, metal-oxide promoters are more efficient because they provide hydroxy sourcesf or removal of carbonaceouss pecies, such as adsorbed CO (CO ads ), at lower potentials. [12][13][14][15][16] Also, metal oxides stabilizeP tc rystallites and avoid their random growth and accumulation during device operation for longert imes. So far,R u, Ce, Ti,V ,N b, Mo, W, Zr, Sn, Mn, Fe, Ni, and Co oxides have been studied as promoters to Pt-based catalysts for the electrooxidation of alcohols.…”

“…So far,R u, Ce, Ti,V ,N b, Mo, W, Zr, Sn, Mn, Fe, Ni, and Co oxides have been studied as promoters to Pt-based catalysts for the electrooxidation of alcohols. [12][13][14][15][16][20][21][22][23][24][25][26] Amongt hese oxides, vanadium(V)o xide (V 2 O 5 )i s ap romisingm aterial for the electrocatalytic oxidation of alcohols. [13,[26][27][28] Vanadium oxide can spread out as am onolayer due to its low Tammannt emperature of 209 8Cc oupled with its low surfacef ree energy.T his resultsi nt he formation of VO x species on the surface that will have an alloying effect with the Pt particles or other oxide phases.…”

Synthesis and Characterization of Ba0.5Sr0.5NixCo0.8‐xFe0.2O3‐δ (x=0 and 0.2) Perovskites as Electro‐catalysts for Methanol Oxidation in Alkaline Media

“…These merits indicate that the modified electrodes show remarkable electro‐catalytic activity for electro‐oxidation of methanol. Notably, the bare CPE showed negligible catalytic activity . Comparing CVs of the modified electrodes (Figure c) showed that the intensity of the oxidation peak currents located at 0.20 V for BSNCF/CPE electrode is 4.24 mA/cm 2 higher than that of BSCF/CPE (3.45 mA/cm 2 ) located at 0.25 V, suggesting that the electro‐catalytic activity for methanol oxidation of the former is higher than that of the latter.…”