Upon receiving his Ph. D in Physics, Mun worked at Intel Corp. before joining Advanced Light Source, Lawrence Berkeley National Laboratory as a beamline scientist in 2002. In 2007, Mun moved to the Hanyang University ERICA in Korea to pursue an academic career, then joined the Gwangju Institute of Science and Technology in 2013.  The main research interest of Mun is to investigate the fundamental correlation between surface chemical properties and electronic structures under reaction conditions. His research utilizes Ambient Pressure X-ray Photoelectron Spectroscopy to uncover atomic-level mechanisms for next-generation energy and environmental technologies. Recently, he started research on interfacial properties of metal oxide multilayers system based on X-ray scattering and hard X-ray photoemission spectroscopy. As his work heavily relies on advanced synchrotron light sources, Mun maintains deep collaborative ties with global facilities.