Imperial College London

Dr Ifan E. L. Stephens

Faculty of EngineeringDepartment of Materials

Senior Lecturer
 
 
 
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Contact

 

+44 (0)20 7594 9523i.stephens Website

 
 
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Location

 

2.03bRoyal School of MinesSouth Kensington Campus

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Summary

 

Summary

Ifan joined Imperial College in July 2017. Prior to Imperial, he was at the Department of Physics at the Technical University of Denmark (DTU); he was first employed as a postdoctoral researcher, then as assistant professor and finally as associate professor and leader of the Electrocatalysis Group there.

In 2015, Massachusetts Institute of Technonlogy (MIT) appointed Ifan as the Peabody Visiting Associate Professor. He taught and conducted research at the Department of Mechanical Engineering at MIT for a whole semester.

Ifan’s research aims to enable the large-scale electrochemical conversion of renewable energy to fuels and valuable chemicals and vice versa. Such processes will be critical in order to allow the increased uptake of renewable energy.  

His focus is on the catalyst at the electrode, i.e. the electrocatalyst. It turns out that the electrocatalyst material defines the efficiency of several important electrochemical processes, including:

(i) electrolysis for the storage of renewable electricity — which is inherently intermittent — in the form of fuels, such as hydrogen or alcohols.
(ii) fuel cells as a potentially zero emission source of power for automotive vehicles.
(iii) the green synthesis of valuable chemicals, such as H2O2.
(iv) batteries, which tend to degrade by gas evolution at the electrode-electrolyte interface. Hence the reactions that need to be accelerated in electrolysers and fuel cells — such as CO2, CO, O2 and H2 evolution — are precisely those that need to be inhibited in batteries.

Ifan has discovered or co-discovered several new catalysts for the oxygen reduction reaction, which exhibited significant improvmements in performance over the prior state-of-the-art (see Selected Publications). In particular, his research on hydrogen peroxide production led to the establishment of the spinout company, HP Now www.hpnow.dk.

Selected Publications

Journal Articles

Escudero-Escribano M, Malacrida P, Hansen MH, et al., 2016, Tuning the activity of Pt alloy electrocatalysts by means of the lanthanide contraction, Science, Vol:352, ISSN:0036-8075, Pages:73-76

Pedersen AF, Ulrikkeholm ET, Escudero-Escribano M, et al., 2016, Probing the nanoscale structure of the catalytically active overlayer on Pt alloys with rare earths, Nano Energy, Vol:29, ISSN:2211-2855, Pages:249-260

Stephens IEL, Bondarenko AS, Gronbjerg U, et al., 2012, Understanding the electrocatalysis of oxygen reduction on platinum and its alloys, Energy & Environmental Science, Vol:5, ISSN:1754-5692, Pages:6744-6762

Stephens IEL, Bondarenko AS, Perez-Alonso FJ, et al., 2011, Tuning the Activity of Pt(111) for Oxygen Electroreduction by Subsurface Alloying, Journal of the American Chemical Society, Vol:133, ISSN:0002-7863, Pages:5485-5491

Greeley J, Stephens IEL, Bondarenko AS, et al., 2009, Alloys of platinum and early transition metals as oxygen reduction electrocatalysts, Nature Chemistry, Vol:1, ISSN:1755-4330, Pages:552-556

Stephens IEL, Rossmeisl J, Chorkendorff I, 2016, Toward sustainable fuel cells, Science, Vol:354, ISSN:0036-8075, Pages:1378-1379

Stephens IEL, Elias JS, Shao-Horn Y, 2015, The importance of being together, Science, Vol:350, ISSN:0036-8075, Pages:164-165

Frydendal R, Paoli EA, Chorkendorff I, et al., 2015, Toward an Active and Stable Catalyst for Oxygen Evolution in Acidic Media: Ti-Stabilized MnO2, Advanced Energy Materials, Vol:5, ISSN:1614-6832

Hernandez-Fernandez P, Masini F, McCarthy DN, et al., 2014, Mass-selected nanoparticles of PtxY as model catalysts for oxygen electroreduction, Nature Chemistry, Vol:6, ISSN:1755-4330, Pages:732-738

Siahrostami S, Verdaguer-Casadevall A, Karamad M, et al., 2013, Enabling direct H2O2 production through rational electrocatalyst design, Nature Materials, Vol:12, ISSN:1476-1122, Pages:1137-1143

More Publications