An Electrocatalytic Activity of AuCeO2/Carbon Catalyst in Fuel Cell Reactions: Oxidation of Borohydride and Reduction of Oxygen

This paper describes the investigation of electrocatalytic activity of the AuCeO2/C catalyst, prepared using the microwave irradiation method, towards the oxidation of sodium borohydride and oxygen reduction reactions in an alkaline medium. It was found that the obtained AuCeO2/C catalyst with Au loading and electrochemically active surface area of Au nanoparticles (AuNPs) equal to 71 µg cm−2 and 0.05 cm2, respectively, showed an enhanced electrocatalytic activity towards investigated reactions, compared with the Au/C catalyst with an Au loading and electrochemically active surface area of AuNPs equal to 78 µg cm−2 and 0.19 cm2, respectively. The AuCeO2/C catalyst demonstrated ca. 4.5 times higher current density values for the oxidation of sodium borohydride compared with those of the bare Au/C catalyst. Moreover, the onset potential of the oxygen reduction reaction (0.96 V) on the AuCeO2/C catalyst was similar to the commercial Pt/C (0.98 V).

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Oxidatively induced exposure of active surface area during microwave assisted formation of Pt3Co nanoparticles for oxygen reduction reaction

RSC Advances ◽

10.1039/c9ra02095k ◽

2019 ◽

Vol 9 (31) ◽

pp. 17979-17987

Author(s):

Robin Sandström ◽

Joakim Ekspong ◽

Eduardo Gracia-Espino ◽

Thomas Wågberg

Keyword(s):

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Surface Area ◽

Microwave Synthesis ◽

Active Surface ◽

Reduction Reaction ◽

Active Surface Area ◽

Microwave Assisted ◽

Electrochemically Active ◽

Electrochemically Active Surface

The oxygen reduction reaction (ORR) is efficiently facilitated platinum catalysts alloyed with Co and reveal high electrochemically active surface area via rapid microwave synthesis.

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The effect of the composition of the dispersing medium of oxide sols on the electrocatalytic activity of sol-gel obtained RuO2-TiO2/Ti anodes

Journal of the Serbian Chemical Society ◽

10.2298/jsc0112847m ◽

2001 ◽

Vol 66 (11-12) ◽

pp. 847-857 ◽

Cited By ~ 4

Author(s):

Dejan Mitrovic ◽

Vladimir Panic ◽

Aleksandar Dekanski ◽

Slobodan Milonjic ◽

Radoslav Atanasoski ◽

...

Keyword(s):

Surface Area ◽

Electrocatalytic Activity ◽

Sol Gel ◽

Active Surface ◽

Proton Exchange ◽

Alcohol Molecule ◽

Active Surface Area ◽

Electrochemically Active ◽

Dispersing Medium ◽

Electrochemically Active Surface

The influence of the addition of methanol, ethanol, 1-propanol and 2-propanol to the dispersing medium of amixture of RuO2 and TiO2 sols on the electrochemically active surface area for proton exchange, as well as on the electrocatalytic activity for the chlorine evolution reaction (CER) of RuO2-TiO2/Ti electrode obtained by sol-gel procedure was investigated. The electrochemically active surface area was examined by cyclic voltammetry, while the analysis of the activity for the CER was performed by polarization measurements. The stability of the obtained anode coatings was also checked by an accelerated stability test. The anode properties depend on the number of C atoms in the alcohol molecule, as well as on the elapsed time between the preparation of the sols/alcohol mixture and its application onto the titanium support. The addition of alcohol increased the activity of the anodes for the CER, compared to those prepared without the addition, but their stability was smaller.

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Ag–Ni core–shell nanowires with superior electrocatalytic activity for alkaline hydrogen evolution reaction

Journal of Materials Chemistry A ◽

10.1039/c7ta04220e ◽

2017 ◽

Vol 5 (32) ◽

pp. 16646-16652 ◽

Cited By ~ 18

Author(s):

Cong Zhang ◽

Sijia Liu ◽

Zhongzhang Mao ◽

Xin Liang ◽

Biaohua Chen

Keyword(s):

Surface Area ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Electrocatalytic Activity ◽

Active Surface ◽

Core Shell ◽

Active Surface Area ◽

Electrochemically Active ◽

Electrochemically Active Surface ◽

Shell Nanowires

Ag–Ni nanowires with high electrochemically active surface area and small impedances were synthesized to show enhanced alkaline HER activity.

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Oxygen Reduction Reaction (ORR) on a Mixed Titanium and Tantalum Oxy-nitride Catalyst Prepared by the Urea-based Sol-gel Method

Journal of New Materials for Electrochemical Systems ◽

10.14447/jnmes.v17i2.424 ◽

2014 ◽

Vol 17 (2) ◽

pp. 055-065 ◽

Cited By ~ 5

Author(s):

A. Seifitokaldani ◽

M. Perrier ◽

O. Savadogo

Keyword(s):

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Surface Area ◽

Sol Gel ◽

Active Surface ◽

Reduction Reaction ◽

Active Surface Area ◽

Gel Method ◽

Sol Gel Method ◽

Onset Potential

The electrochemical stability and activity of different compositions of titanium and tantalum oxy-nitride nano-catalysts were investigated for the oxygen reduction reaction (ORR). A new sol-gel method was used to produce a nano-powder mixture of Ti and Ta oxynitride from their alkoxides using urea as a nitrogen source. The precursors prepared by the sol-gel method were annealed in a N2 + 3% H2 atmosphere at determined temperatures (500, 700 and 900 °C) inside a silica tube furnace. X-ray diffraction results proved that by using this method a considerable amount of nitrogen was inserted into the catalyst structure at a relatively low temperature. Energy dispersive spectroscopy showed that the prepared catalyst should be oxidized carbonitride of titanium and/or tantalum. Heat treatment had a major effect on the onset potential by changing the crystallinity of the catalyst, so that the onset potential of titanium oxynitride increased from ca. 0.05 V to 0.65 V vs. NHE by increasing the temperature from 500 to 700 °C. Increasing the Ta concentration also led to a higher onset potential but lower ORR current. For instance, the onset potential for the ORR for tantalum oxynitride heat treated at 700 °C was ca. 0.85 V vs. NHE while this value was ca. 0.65 V vs. NHE for titanium oxynitride. However, the ORR current was 100 times smaller in tantalum oxynitride, most likely because of a low electrochemically active surface area. Electrochemical measurements suggested that an appropriate composition of titanium and tantalum was required to have both a good onset potential and ORR current by improving the catalytic activity and increasing the active surface area and electrical conductivity.

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