His research centers on energy and environmental policies and strategies, especially on their implementation for achieving energy development and pollution mitigation goals as well as related technological innovation and industrial development. Before joining CUHK in August 2010, Prof. Xu received a Ph.D. degree in public policy from the Woodrow Wilson School of Public and International Affairs, Princeton University and was a postdoctoral research associate in the Industrial Performance Center, Massachusetts Institute of Technology. He also holds an M.S. degree in climatology, a B.S. degree in atmospheric sciences and a bachelor’s degree in economics, all from Peking University.