He moved to Korea and stayed at Sang Ji University (1995 to 1998). In 1999, he joined Sejong University. In 2014, he moved to Dept. of Civil and Environmental Engineering at Hanyang University. His research areas focus on environmental analysis and air quality/human health management based on coordination polymers and other advanced materials. He was awarded a National Star Faculty in 2006. He is serving as an editorial member of several journals (e.g., Environmental Research, Atmospheric Pollution Research, Sensors, and Scientific World). He has published more than 480 SCI journal articles.