2019 - present : Professor, Department of Chemistry, American University of Beirut (AUB), Beirut, Lebanon
2013 - 2019 : Associate Professor, Department of Chemistry, American University of Beirut (AUB), Beirut, Lebanon
2013 July-Aug: Visiting Scholar, Abo Academi University, Turku, Finland
2007 - 2013 : Assistant Professor, Department of Chemistry, American University of Beirut (AUB), Beirut, Lebanon
2010 : Alexander von Humboldt Renewed Research Fellow Drittes Physikalisches Institut, Universität Göttingen, Göttingen, Germany
2006 - 2007 : Visiting Lecturer, Department of Physics, Waseda University, Tokyo, Japan
2005 - 2006 : Japan Society for the Promotion of Sciences (JSPS) Postdoctoral Fellow Department of Physics, Waseda University, Tokyo, Japan
2004 - 2005 :JSPS Postdoctoral Fellow National Institute of Natural Sciences, Okazaki, Japan
2003 : (visiting) Europe Research Fellow, Department of Chemistry, Katholieke Universiteit Leuven, Leuven, Belgium
2002-2004: Alexander von Humboldt Research Fellow Institute of Biological Information Processing – 1 Forschungszentrum, Juelich, Germany
2001-2002 : Postdoctoral Research Fellow, Department of Chemistry, University of Basel, Basel, Switzerland
2001 : Postdoctoral Fellow, Department of Chemistry
Indian Institute of Technology Madras, Chennai, India
Chairperson, Chemistry Department 2020-
Chairman, Undergraduate Admission Committee, FAS, AUB 2013- 2016
Chairman, The Senate University Library Committee, AUB 2015- 2017
Associate Editor, Chemistry Africa, Publisher: Springer 2017- till date
Member, Editorial Board, Research Journal of Chemistry & Environment, 2005-till date
Member, Editorial Board, Current Nanomaterials, 2017- till date
Member, Editorial Board, Karbala International Journal of Modern Science, 2019-