Heterogeneous catalysts play a key role in chemical industry. The development of novel catalysts and the improvement of current ones have been explored in both industry and academia. Fundamental study of molecular and electronic structure of heterogeneous catalyst during synthesis and chemical reaction is important to provide the basis for rational modifications of currently used catalysts and for the design of novel catalysts. Furthermore, understanding the relationships between structure and catalytic performance (e.g., activity, selectivity, and stability) is a crucial step for developing a new catalyst. To do this, large collection of microscopic and spectroscopic techniques is required especially under reaction conditions. In this talk, a brief overview of the characterization techniques at SBU and BNL will be presented. Next, I will present the recent work done at the Energy and Environmental Catalysis Laboratory at Stony Brook University (SBU) and Brookhaven National Laboratory (BNL).