Doctoral defence in Chemical Engineering - Fatemeh Hanifpour

The defence will be streamed live

Ph.D. student: Fatemeh Hanifpour

Dissertation title: Transition metal nitrides and oxynitrides as catalysts for N2 electroreduction to NH3 – from theory to experiments

Opponents: Pr. Douglas Robert MacFarlane, School of Chemistry, Monash University, Australia and
Pr. Plamen Atanassov, School of Chemical and Biomolecular Engineering, University of California Irvine, USA

Supervisor: Egill Skúlason, Professor at the Faculty of Industrial Engineering, Mechanical Engineering and Computer Science at the University of Iceland

Also in the Doctoral Committee: 

Dr. Helga Dögg Flosadóttir, Chief Research Officer at Atmonia, Iceland.
Dr. Kristján Leósson, Chief Scientific Officer at Dynamic Technology Equipment (DTE), Iceland

Chair of Ceremony: Rúnar Unnþórsson, Professor and the Head of the Faculty of Industrial Engineering, Mechanical Engineering and Computer Science

Abstract.

Our world is struggling with the negative impacts of greenhouse gases, with CO2 constituting more than ¾ of them. The ammonia production through the Haber-Bosch process which is vital for the sustain of human beings by ensuring food security, accounts for 1% of the CO2 emissions and is, unfortunately, the only economically viable option as of today. Therefore, a global endeavor towards finding sustainable and carbon-free alternative pathways for ammonia synthesis initiated and peaked during the past decade. The present thesis is one step forward in this path reporting experimental results for electrosynthesis of ammonia via the nitrogen reduction reaction at ambient conditions in aqueous electrolytes. The first and the foremost important factor in these studies is to be able to reliably report data from experiments. This is because the adventitious ammonia from the atmosphere, human breath, laboratory equipment, gas supplies, etc. can emerge as false positives in samples that are hoped to contain ammonia from an electrocatalytic reaction. Due to this fact, a great deal of the endeavors in this work is focused on securing reliable data. The electrochemical cell, ammonia measurement method, and experimental procedures are all chosen and optimized carefully for this aim. The previous theoretical studies in our group have narrowed down the possible choices of electrocatalysts among transition metal nitrides and transition metal oxides. The candidates that are tested in the experiments include ZrN, CrN, NbN, NbO2, and NbON, all in the form of thin-film polycrystalline surfaces. In the electrochemical experiments, various techniques
are employed to study the behaviors of the surfaces in the absence and the presence of the reactive gas that is Ar(g) and N2(g), respectively. Ammonia production in all cases is measured at various applied potentials and compared between the two gas environments. The combined data from electrochemical studies, ammonia measurements, surface analysis before and after experiments, and isotope labeling experiments proves the catalytic/noncatalytic nature of the processes. The results of the studies are presented in the form of one published paper and two submitted papers attached at the end of this thesis.

About the doctoral candidate:

Fatemeh obtained her B.Sc. in 2009 in Chemical Engineering from the University of Tehran, Iran, before further completing a M.Sc. degree in 2011 in Energy Engineering from Sharif University of technology, Iran. She was then involved with the edition of a book titled “Design of Experiments for Engineers” which was published in 2012. From 2013 to 2016, Fatemeh joined the Material Research School of Isfahan, Iran, working on the application of novel materials in the extraction of heavy metals from industrial waste streams, and later started collaboration with the Science and Technology Park of Shahrekord, Iran working on nitrate removal from water and wastewater. In 2016, she started a Ph.D. degree in Chemical Engineering by joining Prof. Egill Skúlason’s group at the University of Iceland. In her Ph.D. studies she has been performing experiments on thin-film catalysts to investigate their performances towards the electrochemical nitrogen reduction reaction at ambient conditions. After her graduation, Fatemeh will start her post-doctoral research at the University of Iceland in collaboration with Atmonia.