- Nano-structured nickel catalyst with thin film deposition technology and succeeded in reducing the content by 1/20
- Suppressing oxidation-reduction destruction of nickel, securing both stability and high performance of ceramic fuel cells
A domestic research team developed a ceramic fuel cell that secured both stability and high performance while reducing the amount of catalyst to 1/20.
Accordingly, it is expected that the application range of ceramic fuel cells, which could only be used for large-scale power generation, can be expanded to new fields due to the difficulty of frequent starting.
The Korea Institute of Science and Technology (KIST, Director Seok-Jin Yoon) is a nickel catalyst in the anode, an electrode in which hydrogen fuel is injected using thin film technology through a joint research by Dr. Jiwon Sohn’s team from the Korea Institute of Science and Technology (KAIST, President Seongcheol Shin). It was revealed that it has developed a new concept technology that suppresses the destruction caused by the oxidation-reduction cycle, which is a major cause of the destruction of ceramic fuel cells by significantly reducing the amount and size of the ceramic fuel cell.
Ceramic fuel cells, which are representative of high-temperature fuel cells, are characterized by high-temperature operation of 800℃ or higher. Thanks to this, the activity is high, and unlike the polymer electrolyte fuel cell, which is a low-temperature fuel cell, uses an expensive, highly active platinum catalyst, an inexpensive catalyst such as nickel can be used. However, when nickel, which constitutes about 40% of the anode by volume , meets and aggregates under high-temperature operating conditions and is exposed to oxidation and reduction processes due to repeated stop-restart, nickel expands and contracts, resulting in the overall structure of the ceramic fuel cell. The fatal disadvantage of being unable to restart several times, leading to the destruction of the ceramic fuel cell, made it difficult to use the ceramic fuel cell for purposes other than large-scale power generation.
Dr. Jiwon Sohn’s team at KIST developed a new concept fuel cell that reduced the nickel content to 2%, 1/20 of the existing anode, so that nickel particles in the anode do not meet and aggregate. By reducing the size of the nickel catalyst to the nanometer level, the surface area was increased to compensate for the decrease in the catalyst content, and the catalyst having a very small size and content was evenly distributed in the anode thin film layer through a thin film process to prevent nickel particles from meeting and agglomeration.
As a result of applying the developed new concept anode to the fuel cell and operating it, there was no destruction of the electrode or deterioration in performance even in cycles exceeding 100 times, which is more than 5 times more stable than the conventional ceramic fuel cell, which was destroyed even in less than 20 oxidation-reduction cycles. . Moreover, the performance of ceramic fuel cells, which was concerned about the decrease in nickel content, was improved by 1.5 times compared to the existing technology due to nano-ization of nickel particles, resulting in remarkable progress in both stability and performance.
Dr. Jiwon Sohn said, “The results of this study are a systematic study of designing and manufacturing-evaluation of a new concept electrode structure that can effectively suppress nickel agglomeration and destruction due to oxidation-reduction, which is the main cause of the destruction of ceramic fuel cells.” “We have confirmed the possibility of improving the operating life by acquiring the stability and performance of ceramic fuel cells at the same time and expanding the range of applications to various fuel cells for transportation and transportation,” he said.
This study was supported by the Ministry of Science and ICT (Minister Ki-Young Choi) and was carried out as a major project in KIST, as a global frontier project for the National Research Foundation of Korea, and a support project for middle-sized researchers. The research results were published in’Acta Materialia’ (IF: 7.656, JCR: 0.633%), the top international academic journal in the field of metal material engineering.