Dr. Pakiza Begum is working as a Research Associate in the Department of Chemistry at Indian Institute of Technology, Guwahati, Assam. She has a consistent first class track record securing the first position in Masters in Chemical Sciences program, Tezpur University. She completed her Ph. D degree availing DST-INSPIRE-JRF and SRF Fellowships from the same University. She was selected for JSPS-HOPE Fellow enabling her to attend the Seventh HOPE Meeting in Tokyo, Japan. She has twelve publications to her credit and all are in reputed International Journals. Her major work has been in Theoretical Chemistry, though she has a few papers involving experiments as well. During Ph. D her study was focused on the activity of Size Selected sub-nano metal and metal-oxide clusters towards conversion of pollutants into less harmful products in the environment. Her experience in the field of conversion of major pollutants like-NO2, CO and hydrocarbons, has led to contributing a chapter in this book.