Recently, Li Wenhao’s project team, Department of Chemistry, College of Sciences, published the latest review of monoatomic catalysts, with the related results titled with From lab-scale to industrialization: atomically M-N-C catalysts for the oxygen reduction reaction published in Energy & Environmental Science, the top journal for materials science. Zhao Tianyou, a doctorial student in College of Sciences, is the first author of this paper, and Professor Li Wenhao from the Department of Chemistry, Assistant Professor Yang Jiarui from the City University of Hong Kong and Professor Wang Dingsheng from Tsinghua University are the corresponding authors of this paper. NEU is the first corresponding institution.
Atomically M-N-C catalysts have become the research hotspot of new energy technology because of its excellent performance in oxygen reduction reaction. Up to now, many types of M-N-C catalysts have been developed as the basic research model to realize efficient fuel cells. In fact, with the help of theoretical research tools at the atomic scale, the understanding of electronic interaction betweenactive sites and micro structures has reached a whole new level. However, there is still a certain distance between lab-scale theoretical construction and industrial development. Therefore, it is particularly urgent to eliminate the gap between lab-scale catalyst research and industrial production for market.
By summarizing the construction, characterization, mechanism research (probe and density functional theory calculation), machine learning and catalyst directional screening design of the active center of M-N-C catalysts at atomic scale, this paper pointed out, for M-N-C catalysts, the key problems to be solved in the industrialization process and the future development direction. With the goal of "accelerating the industrialization process by industrial technology", this paper put forward general views and references for the follow-up research. Firstly, thecomposition and synthesis method of atomically M-N-C catalysts were discussed. Carbon carriers, such as graphene, carbon nanotubes and metal sources, play an important role in improving the performance and stability of catalysts. The main synthesis methods of atomically M-N-C catalysts were introduced: bottom-up and top-down preparation methods. Secondly, the in-situ characterization techniques and deactivation mechanism of the catalysts were discussed. Specifically, in-situ characterization techniques include electrochemical in-situ X-ray spectroscopy, electrochemical in-situ spectroscopy, and in-situ characterization of MEA. These techniques enable researchers to monitor the dynamic changes of catalysts in the reaction process in real time. In addition, the deactivation mechanism of atomically M–N–C catalysts was explored with chemical probe method. In order to improve the overall performance of the catalysts, in this paper, various control strategies were introduced in detail, such as optimizing the distribution of active sites, adjusting the structure of supporting materials and synthesis conditions, thus effectively prolonging the service life of the catalyst and improving its stability. Thirdly, the application of machine learning (ML) and theoretical calculation (such as density functional theory, DFT) in catalyst design was discussed. ML can help to accelerate the catalyst screening process, predict the performance of the catalyst and provide support for the optimal design of the catalyst. Through theoretical calculation, researchers can better understand the structure-performance relationship of active center of catalyst, hence providing theoretical basis for catalyst optimization. Fourthly, the possible challenges in the process of catalyst industrialization were discussed, including the following aspects: synthesis raw materials and catalytic materials of atomically M-N-C catalysts, evaluation methods from lab-scale to industrialization, and the attenuation mechanism of catalysts under actual working conditions. Besides, the application of ML in catalyst design and its potential in accelerating catalyst industrialization were also discussed in this paper.
In this paper, the application potential of atomically M–N–C catalysts in the field of energy conversion and storage, especially oxygen reduction reaction (ORR) was discussed. This paper summarized the progress of these catalysts from laboratory research to industrial application, analyzed the synthesis method, material optimization, deactivation mechanism, evaluation method and the role of machine learning, and provided theoretical support for promoting their large-scale application. Moreover, this paper also pointed out the key problems to be solved in the process of catalyst industrialization, such as stability, performance, production process and cost control, which is of great significance to academic research and practical application.
