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University of Belgrade - Institute of Chemistry, Technology and Metallurgy - National Institute of the Republic of Serbia, Department of Electrochemistry, Njegoševa 12 , Belgrade , Serbia
Center of Excellence in Environmental Chemistry and Engineering, Institute of Chemistry, Technology and Metallurgy, Njegoševa 12 , Belgrade , Serbia
Center of Excellence in Environmental Chemistry and Engineering, Institute of Chemistry, Technology and Metallurgy, Njegoševa 12 , Belgrade , Serbia
University of Belgrade - Institute of Chemistry, Technology and Metallurgy - National Institute of the Republic of Serbia, Department of Electrochemistry, Njegoševa 12 , Belgrade , Serbia
University of Belgrade, Innovation Center of Faculty of Technology and Metallurgy, Karnegijeva 4 , Belgrade , Serbia
University of Belgrade - Institute of Chemistry, Technology and Metallurgy - National Institute of the Republic of Serbia, Department of Electrochemistry, Njegoševa 12 , Belgrade , Serbia
University of Belgrade - Institute of Chemistry, Technology and Metallurgy - National Institute of the Republic of Serbia, Department of Electrochemistry, Njegoševa 12 , Belgrade , Serbia
Center of Excellence in Environmental Chemistry and Engineering, Institute of Chemistry, Technology and Metallurgy, Njegoševa 12 , Belgrade , Serbia
Center of Excellence in Environmental Chemistry and Engineering, Institute of Chemistry, Technology and Metallurgy, Njegoševa 12 , Belgrade , Serbia
University of Belgrade - Institute of Chemistry, Technology and Metallurgy - National Institute of the Republic of Serbia, Department of Electrochemistry, Njegoševa 12 , Belgrade , Serbia
University of Belgrade - Institute of Chemistry, Technology and Metallurgy - National Institute of the Republic of Serbia, Department of Electrochemistry, Njegoševa 12 , Belgrade , Serbia
Center of Excellence in Environmental Chemistry and Engineering, Institute of Chemistry, Technology and Metallurgy, Njegoševa 12 , Belgrade , Serbia
State University of Novi Pazar,Vuka Karadžića bb , Novi Pazar , Serbia
Water electrolysis, powered by sustainable energy sources, represents a key technology for a green hydrogen production, offering a clean and renewable energy solution. However, the efficiency of this process is primarily constrained by the sluggish kinetics of the oxygen evolution reaction (OER), which significantly increases the overall energy demands. To overcome this limitation, highly active and stable OER catalysts are required to enhance reaction efficiency and reduce energy losses. Among the known OER catalysts, iridium(IV) oxide (IrO2) is considered the most effective due to its exceptional activity and durability in acidic environments. Nevertheless, given the high cost and scarcity of iridium, optimizing its utilization and catalytic efficiency is crucial. This can be achieved through the development of advanced synthesis strategies and the incorporation of interactive supporting materials that enhance catalytic performance while minimizing Ir consumption. This study presents an innovative synthesis approach that combines ultrasonic spray pyrolysis (USP) for the preparation of rare-earth-based oxide as catalyst carrier with their subsequent microwave hydrothermal encapsulation by IrO2. Ce/Y (∑M) oxide supports were synthesized using a one-step USP process in which precursor aqueous solutions of CeCl3 and Y(NO3)3 were mixed in mole ratios of Ce:Y=4:1 and Ce:Y=1:4. The conversion temperature during spray pyrolysis was regulated using a thermostated furnace, ensuring uniform particle formation and phase composition. The nebulization and aerosol formation process was carried out in an oxygen atmosphere, with a controlled carrier gas (oxygen) flow rate of 2 dm3 min⁻1, while the synthesis temperature was maintained at 800 °C to promote the formation of CeO2/Y2O3 composite structures with the desired crystallinity and morphology. Following the synthesis of oxide USP powders, the materials were further processed via microwave hydrothermal treatment in the presence of IrCl3 under constant temperature conditions, leading to the formation of composite materials with varying IrO2 mole ratios (projected to ∑M:Ir=3:7 and ∑M:Ir=7:3). The resulting composites of IrO2-shelled CeO2/Y2O3 microspheres were systematically characterized to assess their electrochemical properties and catalytic activity for OER. Particular emphasis was placed on evaluating the synergistic effects of CeO2 and Y2O3 within the composite structures, as well as their role in enhancing the catalytic performance of IrO2. The study provides insight into how the interaction between these oxide catalyst carriers and IrO2 influences overall OER efficiency, shedding light on potential strategies for improving the sustainability and cost-effectiveness of high-performance water-splitting catalysts.
oxygen evolution reaction, oxygen-evoloving anodes, electrocatalytic powders, electrochemical charaterizationo of powders
Acknowledgement: Authors wish to acknowledge the support of the Science Fund of the Republic of Serbia PROJECT NUMBER 6666, Renewal of the Waste Oxygen-Evolving anodes from Hydrometallurgy and their improved Activity for Hydrogen Economy, Wastewater and Soil Remediation - OxyRePair.
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