Thermogravimetric and x-ray diffraction analyses on cerate-zirconate powder prepared via different chelating agents / Nur Ainul Syaizrah Azman

Developing SOFCs with a proton-conducting ceramic oxide as the electrolyte, also known as proton ceramic fuel cells (PCFCs), is widely investigated. Ceramic powder based on cerate-zirconates has a wide range of applications, including use as a solid electrolyte in SOFCs. Wet chemical methods (WCMs), such as the sol-gel technique, are commonly used in research laboratories because they can produce high purity powders at relatively low temperatures. The powder of BaCe0.54Zr0.36Y0.1O2.95 (BCZY) was synthesised using a sol-gel process aided by chelating agents in this study. Citric acid, triethylenetetramine (TETA), and ethylenediaminetetraacetic acid (EDTA) were used as chelating agents. The result of powder properties was characterised using thermogravimetric analysis (TGA) and an X-Ray diffractometer (XRD). The samples were dried at 325 °C and calcined at various temperatures. TGA was used to study the thermal behaviour of dried samples, and the results revealed that all of the samples almost fully decomposed at 1000 °C. It was discovered that the amount of organic compounds produced during thermal breakdown of samples increased as the molecular weight of chelating agents increased. TGA confirmed that the weight loss of intermediate compounds increased as the chelating agents' molecular weight, Mw, increased as following: A3 (35%) < A1 (93%) < A2 (95%). Except for the sample prepared with TETA, all of the samples required processing at substantially higher temperatures to eliminate the carbonates impurities. The XRD patterns of all samples demonstrated successful production of single-phase BCZY crystals at a calcination temperature of 1100 °C. A3 has the highest percentage of BCZY perovskite phase which is 98.9%. XRD measurements confirm that the sample generated with TETA has a high crystalline of BCZY powders. Hence, TETA was discovered to be the best chelating agent in collaborating with metal nitrate salts to produce a pure phase of BCZY powders.