Prof. Leung's main research interests include solar photocatalysis, fuel cell, hydrogen power, advanced refrigeration/air-conditioning and carbon management. His research is well recognized as he is listed among the top 2% of the world’s most highly cited scientists published by Stanford University. He is also listed in Highly Cited Researchers 2018 by Clarivate Analytics that recognizes world-class researchers selected for their exceptional research performance. He is also listed in The Most Cited Researchers in Energy Science and Engineering, Developed for ShanghaiRanking's Global Ranking of Academic Subjects by Elsevier. Prof. Leung has totally received HK$40M+ research funding as a PI from ITF, RGC, NSFC, ECF, SDF, industrial sponsorships, university internal grants, donations, etc. He has published 200+ journal papers, 80+ conference papers, 18 books/book chapters, and 10 patents.