| Optimization of effective parameters in preparation of IrO2 and RuO2 catalyst inks for use in the oxygen evolution reaction in acidic media |
| کد مقاله : 1031-CNF (R1) |
| نویسندگان |
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هایده بلالی دهکردی *1، محمد ژیانی2، محمد محمدی2، پردیس نادراصلی3 1دانشگاه صنعتی اصفهان 2انجمن 3دانشگله صنعتی اصفهان |
| چکیده مقاله |
| Hydrogen (H2) is an efficient energy carrier used to grid scale energy storage. Polymer electrolyte membrane water electrolyzers (PEMWEs) provide a pathway for clean and carbon-free hydrogen generation for both transportation and industrial uses. In PEMWE, water is electrochemically divided into hydrogen at the cathode and oxygen at the anode. Oxygen evolution reaction kinetics is one of the limiting factors in PEMWE performance. One of the factors influencing the kinetics of this reaction is the microstructure of the catalyst used to slow kinetic of the OER reaction, which strongly affects the mass transport and other properties and therefore plays a key role in the efficiency of oxygen and ultimately hydrogen production. The catalyst microstructure is formed by the catalyst particles and usually nafion 5 wt% that acts as a binder for the catalyst particles. This paper deals with the optimization structure and the preparation operations of catalyst inks used in water electrolysis. The ink consists of iridium oxide (IrO2) catalyst particles and ruthenium oxide (RuO2) and nafion dispersed in a mixture of 1-propanol and water. After mixing the components, the ink becomes homogeneous and dispersed with the help of small zirconia pellets and an ultrasonic bath. Since in ultrasonic bath, ultrasonic waves cause intense mobility of particles and increase their kinetic energy and thus increase the ink temperature, choosing the optimal time to use ultrasonic bath is very important. The temperature parameter during ink dispersion in the ultrasonic bath has a major effect on the homogenization efficiency by increasing the vapor pressure and changing the solvent and bubble dynamics. One strategy for controlling the ultrasonic catalyst ink slurry is to use an ice bath (to ensure rapid heat dissipation). For this purpose, a glass container containing catalyst ink slurry is placed in a water and ice bath at a temperature of less than zero degrees. Although it is a simple method, the main problem is that the ultrasonic energy is absorbed by the ice and therefore the ice must be replaced by applying long ultrasonic times. Another method that can be used for this purpose is to use pulsed ultrasonics instead of continuous ultrasonics. Here, these two methods were used for homogenization. Using several catalyst samples and performing three-electrode tests on the inks made from them, the optimal time of 30 minutes was selected for sonicating in ultrasonic bath. The effects of catalyst concentration and its preparation on the microstructure of catalyst ink have also been studied here. Studies have shown that the concentration of catalysts as well as the ratio of the composition of deionized water and isopropyl affect the kinetics of the OER reaction. The 1:1ratio of water : isopropyl and a concentration of 500 ppm of catalyst show better results. |
| کلیدواژه ها |
| Oxygen evolution reaction, Acidic media, Catalyst inks, Iridium oxide, Ruthenium oxide |
| وضعیت: چکیده برای ارائه به صورت پوستر پذیرفته شده است |