Synthesis and Optimisation of IrO2 Electrocatalysts by Adams Fusion Method for Solid Polymer Electrolyte Electrolysers

Maiyalagan, T.; Pasupathi, Sivakumar; Bladergroen, Bernard Jan; Linkov, Vladimir

doi:10.2174/1876402911204030186

Cited by 38 publications

(57 citation statements)

References 23 publications

(28 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[43][44][45][46]48,[62][63][64] In the majority of those studies, both activity and stability were estimated by studying currentpotential profiles. For instance, based on an accelerated corrosion test by detecting electrode end-of-life, Kötz and Stucki showed that in comparison to pure RuO 2 the corrosion rate of the mixed Ir-Ru oxide anodes is at least an order of magnitude lower.…”

Section: Discussionmentioning

confidence: 99%

On the Origin of the Improved Ruthenium Stability in RuO₂–IrO₂Mixed Oxides

Kasian

Geiger

Stock

et al. 2016

J. Electrochem. Soc.

114

View full text Add to dashboard Cite

High oxygen evolution reaction activity of ruthenium and long term stability of iridium in acidic electrolytes make their mixed oxides attractive candidates for utilization as anodes in water electrolyzers. Indeed, such materials were addressed in numerous previous studies. The application of a scanning flow cell connected to an inductively coupled plasma mass spectrometer allowed us now to examine the stability and activity toward oxygen evolution reaction of such mixed oxides in parallel. The whole composition range of Ir-Ru mixtures has been covered in a thin film material library. In the whole composition range the rate of Ru dissolution is observed to be much higher than that of Ir. Eventually, due to the loss of Ru, the activity of the mixed oxides approaches the value corresponding to pure IrO 2 . Interestingly, the loss of only a few percent of a monolayer in Ru surface concentration results in a significant drop in activity. Several explanations of this phenomenon are discussed. It is concluded that the herein observed stability of mixed Ir-Ru oxide systems is most likely a result of high corrosion resistance of the iridium component, but not due to an alteration of the material's electronic structure. Renewable primary energies such as solar energy, wind energy and ocean energy receive more and more attention and are increasingly installed around the world.1-3 It is anticipated that renewables will eventually replace traditional fossil fuel-burning and nuclear power plants. However, intermittent power supply of renewables means that energy needs to be buffered. Thereby, hydrogen produced by water electrolysis is considered as an ideal energy carrier to adjust the balance between the generation of power by renewable primary energy and energy demand for end-use.3-5 Currently, acidic proton exchange membrane water electrolysis (PEMWE) is considered as a promising technology for this purpose. However, the widespread use of PEMWE is hindered by high capital costs, low efficiency, and shortages related to performance deterioration with time. 6 In this connection the nature of electrocatalysts and the procedure of their production and application conditions play a critical role. Materials used as electrocatalysts must be as active as possible to improve efficiency, while at the same time they need to be stable to maintain this efficiency throughout the lifetime of the electrolyzer. This is especially critical for materials catalyzing the anodic oxygen evolution reaction (OER), because of the detrimental positive potential and highly corrosive acidic environment. Only a few catalysts are able to withstand these harsh conditions, while providing sufficient activity, conductivity and mechanical stability. In fact, only iridium oxide anodes are proven to provide the required longevity of operation. On the other hand, ruthenium shows the highest electrocatalytic activity toward this reaction. 7,8 During the last decades, the electrochemical and surface properties of anodes based on these metals and their oxides we...

show abstract

Section: Discussionmentioning

confidence: 99%

On the Origin of the Improved Ruthenium Stability in RuO₂–IrO₂Mixed Oxides

Kasian

Geiger

Stock

et al. 2016

J. Electrochem. Soc.

114

View full text Add to dashboard Cite

show abstract

“…Since no inexpensive and suitable replacement for Ir has been found so far, current research efforts are directed toward a more efficient utilization of Ir based catalysts. 4 Nanoparticulated materials efficiently dispersed on a support, [5][6][7][8] highly porous layers, [9][10][11] core shell 12,13 and mixed oxide systems [14][15][16] have been suggested to reduce the loading of expensive elements. An alternative way is the structural modification of iridium oxides, e.g.…”

mentioning

confidence: 99%

“…Therefore, 5 h tests cannot guarantee that the investigated material is indeed stable. Other authors used chronoamperometry for 0.5 h 34 or chronopotentiometry for 15 h, 6 25 h 36 and 120 h. 5 Instead, investigation of the actual loss of active material directly during polarization can be very helpful to assess the stability on a long run. 37 Such data can be used for estimation of the electrodes end-of-life.…”

mentioning

confidence: 99%

Activity and Stability of Electrochemically and Thermally Treated Iridium for the Oxygen Evolution Reaction

Geiger

Kasian

Shrestha

et al. 2016

J. Electrochem. Soc.

165

174

View full text Add to dashboard Cite

Iridium is the main element in modern catalysts for the oxygen evolution reaction (OER) in proton exchange membrane water electrolyzers (PEMWE), which is predominantly due to its relatively good activity and tolerable stability in harsh PEMWE conditions. Limited abundance of iridium, however, poses limitations on widespread applications of these devices, in particular in the large scale conversion and storage of renewable energy. In this work we investigate if the electrocatalytic performance of iridium can be fine-tuned by thermal treatment of catalysts at different temperatures. The OER activity and the dissolution of two different iridium electrodes, viz. (a) flat metallic iridium surfaces prepared by electron beam physical vapor deposition (EBPVD) and (b) electrochemically prepared porous hydrous iridium oxide films (HIROF) are studied. The range of applied annealing temperatures is 100 • C-600 • C, with a general trend of decreasing activity and increasing stability the higher the temperature. Numerous peculiarities in the trend are however observed. These are discussed considering variations of oxide structure, morphology and electronic conductivity.

show abstract

“…IrO 2 was synthesised using an adaptation of Adams’ fusion method that is widely applied to the synthesis of noble metal oxide nanoparticles [51,54,55]. The original method involves fusion of a metal chloride precursor with NaNO 3 in air at an elevated temperature, resulting in the formation of the metal oxide and NaCl.…”

Section: Methodsmentioning

confidence: 99%

Carbon Nitride Materials as Efficient Catalyst Supports for Proton Exchange Membrane Water Electrolyzers

et al. 2018

View full text Add to dashboard Cite

Carbon nitride materials with graphitic to polymeric structures (gCNH) were investigated as catalyst supports for the proton exchange membrane (PEM) water electrolyzers using IrO2 nanoparticles as oxygen evolution electrocatalyst. Here, the performance of IrO2 nanoparticles formed and deposited in situ onto carbon nitride support for PEM water electrolysis was explored based on previous preliminary studies conducted in related systems. The results revealed that this preparation route catalyzed the decomposition of the carbon nitride to form a material with much lower N content. This resulted in a significant enhancement of the performance of the gCNH-IrO2 (or N-doped C-IrO2) electrocatalyst that was likely attributed to higher electrical conductivity of the N-doped carbon support.

show abstract

Synthesis and Optimisation of IrO2 Electrocatalysts by Adams Fusion Method for Solid Polymer Electrolyte Electrolysers

Cited by 38 publications

References 23 publications

On the Origin of the Improved Ruthenium Stability in RuO₂–IrO₂Mixed Oxides

On the Origin of the Improved Ruthenium Stability in RuO₂–IrO₂Mixed Oxides

Activity and Stability of Electrochemically and Thermally Treated Iridium for the Oxygen Evolution Reaction

Carbon Nitride Materials as Efficient Catalyst Supports for Proton Exchange Membrane Water Electrolyzers

Contact Info

Product

Resources

About

Synthesis and Optimisation of IrO2 Electrocatalysts by Adams Fusion Method for Solid Polymer Electrolyte Electrolysers

Cited by 38 publications

References 23 publications

On the Origin of the Improved Ruthenium Stability in RuO2–IrO2Mixed Oxides

On the Origin of the Improved Ruthenium Stability in RuO2–IrO2Mixed Oxides

Activity and Stability of Electrochemically and Thermally Treated Iridium for the Oxygen Evolution Reaction

Carbon Nitride Materials as Efficient Catalyst Supports for Proton Exchange Membrane Water Electrolyzers

Contact Info

Product

Resources

About

On the Origin of the Improved Ruthenium Stability in RuO₂–IrO₂Mixed Oxides

On the Origin of the Improved Ruthenium Stability in RuO₂–IrO₂Mixed Oxides