Ex-Situ Electrochemical Characterization of IrO2 Synthesized by a Modified Adams Fusion Method for the Oxygen Evolution Reaction

The development of highly stable and active electrocatalysts for the oxygen evolution reaction (OER) has attracted significant research interest. IrO2 is known to show good stability during the OER however it is not known to be the most active. Thus, significant research has been dedicated to enhance the activity of IrO2 toward the OER. In this study, IrO2 catalysts were synthesized using a modified Adams fusion method. The Adams fusion method is simple and is shown to directly produce nano-sized metal oxides. The effect of the Ir precursor salt to the NaNO3 ratio and the fusion temperature on the OER activity of the synthesized IrO2 electrocatalysts, was investigated. The OER activity and durability of the IrO2 electrocatalysts were evaluated ex-situ via cyclic voltammetry (CV), chronopotentiometry (CP), electrochemical impedance spectroscopy (EIS) and linear sweep voltammetry (LSV). Physical properties of the IrO2 electrocatalysts were evaluated via X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), differential thermal analysis (DTA), and energy dispersive spectroscopy (EDS). The results show that the addition of excess NaNO3 during the modified Adams fusion reaction is not a requirement and that higher synthesis temperatures results in IrO2 electrocatalysts with larger particle sizes and reduced electrocatalytic activity.

[1]  R. Kötz,et al.  Oxygen evolution and reduction on iridium oxide compounds , 1995 .

[2]  R. Shriner,et al.  PLATINUM OXIDE AS A CATALYST IN THE REDUCTION OF ORGANIC COMPOUNDS. III. PREPARATION AND PROPERTIES OF THE OXIDE OF PLATINUM OBTAINED BY THE FUSION OF CHLOROPLATINIC ACID WITH SODIUM NITRATE1 , 1923 .

[3]  T. Maiyalagan,et al.  Synthesis and optimisation of IrO2 electrocatalysts by Adams fusion method for solid polymer electrolyte electrolysers , 2012 .

[4]  C. D. Pauli,et al.  Electrochemical surface characterization of IrO 2 + SnO 2 mixed oxide electrocatalysts , 1995 .

[5]  Ping Liu,et al.  Reaction mechanism for oxygen evolution on RuO2, IrO2, and RuO2@IrO2 core-shell nanocatalysts , 2017, Journal of Electroanalytical Chemistry.

[6]  Huamin Zhang,et al.  Study of carbon-supported IrO2 and RuO2 for use in the hydrogen evolution reaction in a solid polymer electrolyte electrolyzer , 2010 .

[7]  Yuanbing Mao,et al.  Ultrafine Iridium Oxide Nanorods Synthesized by Molten Salt Method toward Electrocatalytic Oxygen and Hydrogen Evolution Reactions , 2016 .

[8]  Aleksandar R. Zeradjanin,et al.  Stability of nanostructured iridium oxide electrocatalysts during oxygen evolution reaction in acidic environment , 2014 .

[9]  M. Mehrpooya,et al.  A comprehensive review on coupling different types of electrolyzer to renewable energy sources , 2018, Energy.

[10]  Cheng Wang,et al.  Investigation of high-performance IrO2 electrocatalysts prepared by Adams method , 2018, International Journal of Hydrogen Energy.

[11]  B. Yi,et al.  Electrochemical investigation of electrocatalysts for the oxygen evolution reaction in PEM water electrolyzers , 2008 .

[12]  Huamin Zhang,et al.  Preparation of Ir0.4Ru0.6MoxOy for oxygen evolution by modified Adams’ fusion method , 2009 .

[13]  M. Busch,et al.  Revisiting the Redox Properties of Hydrous Iridium Oxide Films in the Context of Oxygen Evolution , 2013 .

[14]  S. Hackwood,et al.  Amorphous-nonmetal-to-crystalline-metal transition in electrochromic iridium oxide films , 1982 .

[15]  W. Sugimoto,et al.  Oxygen reduction behavior of rutile-type iridium oxide in sulfuric acid solution , 2008 .

[16]  Z. Mao,et al.  Preparation of nanometer-sized SnO2 by the fusion method , 2007 .

[17]  K. Ayers,et al.  Nano-size IrOx catalyst of high activity and stability in PEM water electrolyzer with ultra-low iridium loading , 2018, Applied Catalysis B: Environmental.

[18]  E. Arashiro,et al.  Voltammetric characterization of an iridium oxide-based system: the pseudocapacitive nature of the Ir0.3Mn0.7O2 electrode , 2002 .

[19]  Aaron T. Marshall,et al.  Electrochemical characterisation of IrxSn1−xO2 powders as oxygen evolution electrocatalysts , 2006 .

[20]  D. Tsai,et al.  Synthesis and structural characterization of twinned V-shaped IrO2 nanowedges on TiO2 nanorods via MOCVD , 2009 .

[21]  S. Sotiropoulos,et al.  Electrochemical impedance studies of IrO2 catalysts for oxygen evolution , 2015 .

[22]  S. Sunde,et al.  Electronic structure vs. electrocatalytic activity of iridium oxide , 2010 .

[23]  P. Patil,et al.  Substrate temperature dependent structural, optical and electrical properties of spray deposited iridium oxide thin films , 2003 .

[24]  Y. Murakami,et al.  Preparations of ultrafine IrO2-SnO2 binary oxide particles by a sol-gel process , 1994 .

[25]  R. Shriner,et al.  THE PREPARATION OF PALLADOUS OXIDE AND ITS USE AS A CATALYST IN THE REDUCTION OF ORGANIC COMPOUNDS.1 VI , 1924 .

[26]  V. Antonucci,et al.  Investigation of IrO2 electrocatalysts prepared by a sulfite-couplex route for the O2 evolution reaction in solid polymer electrolyte water electrolyzers , 2011 .

[27]  M. Povia,et al.  Iridium Oxide for the Oxygen Evolution Reaction: Correlation between Particle Size, Morphology, and the Surface Hydroxo Layer from Operando XAS , 2016 .

[28]  Ji-Ming Hu,et al.  Microstructure, electrochemical surface and electrocatalytic properties of IrO2+Ta2O5 oxide electrodes , 2003 .

[29]  San Ping Jiang,et al.  Advances in electrocatalysts for oxygen evolution reaction of water electrolysis-from metal oxides to carbon nanotubes , 2015 .

[30]  Ji-Ming Hu,et al.  Degradation mechanism of long service life Ti/IrO2–Ta2O5 oxide anodes in sulphuric acid , 2002 .

[31]  D. Stolten,et al.  A comprehensive review on PEM water electrolysis , 2013 .

[32]  S. Sunde,et al.  Performance of a PEM water electrolysis cell using IrxRuyTazO2 electrocatalysts for the oxygen evolution electrode , 2007 .

[33]  M. Hara,et al.  Synthesis and electrochemical analysis of novel IrO2 nanoparticle catalysts supported on carbon nanotube for oxygen evolution reaction , 2018, International Journal of Hydrogen Energy.

[34]  B. Peppley,et al.  Study of the Effect of Calcination Temperature on the Morphology and Activity of Iridium Oxide Electrocatalyst Supported on Antimony Tin Oxide (ATO) for PEM Electrolyser Technology , 2015 .

[35]  K. Scott,et al.  Physical and electrochemical evaluation of ATO supported IrO2 catalyst for proton exchange membrane water electrolyser , 2014 .

[36]  Egil Rasten.  Electrocatalysis in water electrolysis with solid polymerelectrolyte , 2003 .