2, Zhejiang University, Hangzhou, Zhejiang, China
Chemistry, especially heterogeneous catalysis, has a pivotal role in solving the global challenges of energy and environment. This is not only because catalysts are involved in 85% of the daily synthesis of materials, but also because they contribute to the effective energy storage. Revolutionary advances in catalysis research, instead of evolutionary developments, is required by the society as the risk of disturbing the thermal equilibrium system of the planet getting more and more serious. Conventional transmission electron microscopy (CTEM) has been widely used for characterizing the microstructure of the catalyst particles before and after the reaction. Knowledge of particle size distribution, chemical composition, crystal, atom and electronic structure, greatly helps us to understand the structure information of the catalyst at its stable states. However, the working structure of a catalyst is often a transient, metastable form, and thus highly dependent to the reaction environment. In order to fully understand the catalytic mechanism, catalysts are needed to be studied during the catalytic reaction. This is not possible in CTEM, due to the high vacuum environment and room temperature limitation of CTEM. Using the latest nano-reactor technology, we have realized the high-pressure gas and high-temperature environment (10 ^ 5 Pa, 1000 ° C) required for chemical synthesis and catalyst reaction inside the electron microscope maintaining the characterization power of TEM. The entire workflow of catalysis, starting from preparation/synthesis of the catalyst, evaluation of the reaction activity and characterization of the real-time structure dynamics can be observed directly in TEM at atomic level, exampled by in situ characterization of Cu, Ni catalysts. Through these results, we would like to demonstrate that in situ TEM provides a revolutionary approach to catalysis research.