Royal Society University Research Fellow
Sam Stranks is accepting applications for PhD students.
JJ Thomson Ave
Kapitza Building K26
Cambridge CB3 0HE
Sam Stranks is a TED Fellow and a Royal Society University Research Fellow at the University of Cambridge. He graduated from the University of Adelaide in 2007 with a BA (German and Applied Mathematics), BSc (Physics and Physical Chemistry), BSc (First Class Honours in Physics) and a University Medal. He completed his PhD as a Rhodes Scholar at Oxford University with Robin Nicholas, receiving the 2012 Institute of Physics Roy Thesis Prize for his work on carbon nantoube/polymer blends for organic solar cell applications. From 2012-2014, he worked as a post-doctoral researcher in Henry Snaith’s group at Oxford University where he was also a Junior Research Fellow at Worcester College and Lecturer in Physics at Corpus Christi College. From 2014-2016, he was a Marie Curie Outgoing Fellow at the Massachusetts Institute of Technology undertaking independent research in Vladimir Bulovic's ONE Lab. Sam received the 2016 IUPAP Young Scientist in Semiconductor Physics Prize for 'pioneering discoveries in the field of perovskite solar cells and optoelectronics through spectroscopy”.
Our research generally focuses on the optical and electronic properties of emerging photovoltaic and optoelectronic systems. We use spectroscopic techniques to assess the optoelectronic quality of materials and construct optimised devices including solar cells, light-emitting diodes and lasers. We are particularly interested in understanding the photophysical properties and potential device applications of new absorber and emitter materials including metal halide perovskites and related materials. See my recent TED talk on our work on perovskites.
Our approaches include:
- Time-resolved techniques including time-correlated single photon counting (TCSPC), photoinduced absorption (PIA) and transient absorption (TAS)
- Time-resolved confocal photoluminescence and electroluminescence mapping
- Steady-state photoluminescence and absorption spectroscopy
- Perovskite, hybrid and organic photovoltaic and light-emitting device fabrication and characterisation
- Scanning electron microscopy (SEM) with energy-dispersive X-Ray (EDX) spectroscopy and X-Ray Photoelectron Spectroscopy (XPS)
- X-Ray Diffraction (XRD)
- Carbon nanotube–polymer nanohybrid synthesis and characterisation
Please get in touch if you are interested in joining the group. Some specific PhD projects on offer for 2017 are listed below, though please also get in touch if other areas of my research are of interest. The deadlines for application to the University are typically in early December for international students for a start date the following October.
1. Understanding the origin of non-radiative losses in perovskite films
2. Direct relationship between local structure and local optoelectronic behaviour in perovskites
3. Investigating the origin of slow charge carrier recombination in metal halide perovskites
4. Eliminating non-radiative losses in materials for perovskite-perovskite tandems
5. Developing high-performance perovskite white light LEDs
Selected recent peer-reviewed publications:
- Hutter, E. M.; Osherov, A.; Gelvez-Rueda, M. C.; Bulovic, V.; Grozema, F. C.; *Stranks, S. D.; *Savenije, T. Direct-Indirect Bandgap Character of the Band Gap in Methylammonium Lead Iodide Perovskite, Nat. Mater., 2016, DOI: 10.1038/nmat4765
- Osherov, A., Hutter, E. M., Galkowski, K., Brenes, R., Maude, D. K., Nicholas, R. J., Plochocka, P., Bulović, V., Savenije, T. J., *Stranks, S. D. The Impact of Phase Retention on the Structural and Optoelectronic Properties of Metal Halide Perovskites, Adv. Mater., 2016, DOI: 10.1002/adma.201604019
- Stranks, S. D. Petrozza, A. Revisiting photocarrier lifetimes in photovoltaics, Nat. Photon., 2016,10, 562
- *Barbero, D. R.; *Stranks, S. D. Functional Single-Walled Carbon Nanotubes and Nanoengineered Networks for Organic- and Perovskite-Solar-Cell Applications, Adv. Mater., 2016, DOI: 10.1002/adma.201600659
- deQuilettes, D. W.; Zhang, W.; Burlakov, V. M.; Graham, D. J.; Leijtens, T.; Bulovic, V.; Ginger, D. S.; Snaith, H. J., Stranks, S. D. Photo-Induced Halide Redistribution in Organic-Inorganic Perovskite Films, Nat. Commun., 2016, 7, 11683
- Stranks, S. D.; Snaith, H. J. Metal-Halide Perovskites for Photovoltaic and Light Emitting Devices, Nat. Nanotechnol., 2015, 10, 391-402
- deQuilettes, D. W.; Vorpahl, S. M.; Stranks, S. D.; Nagaoka, H.; Eperon, G. E.; Ziffer, M. E.; Snaith, H. J.; Ginger, D. S., Impact of Microstructure on Local Carrier Lifetime in Perovskite Solar Cells. Science, 2015, 348, 683-686
- Sivaram, V.; Stranks, S. D.; Snaith, H. J. Outshining silicon, Scientific American, 2015, 313, 54-49
- Miyata, A.; Mitioglu, A.; Plochocka, P.; Portugal, O.; Wang, J. T. W.; Stranks, S. D.; Snaith, H. J.; Nicholas, R. J., Direct Measurement of the Exciton Binding Energy and Effective Masses for Charge carriers in Organic-Inorganic Tri-halide Perovskites. Nat. Physics, 2015, 11, 582-587
- Stranks, S. D.; Wood, S. M.; Wojciechowski, K.; Deschler, F.; Saliba, M.; Khandelwal, H.; Patel, J. B.; Elston, J. S.; Herz, L. M.; Johnston, M. B.; Schenning, A. P. H. J.; Debije, M. G.; Riede, M. K.; Morris, S. M.; Snaith, H. J. Enhanced Amplified Spontaneous Emission in Perovskites using a Liquid Crystal Reflector, Nano Lett., 2015, 15, 4935-4941
- Stranks, S. D.; Burlakov, V. M.; Leijtens, T.; Ball, J. M.; Goriely, A.; Snaith, H. J. Recombination Kinetics in Organic-Inorganic Perovskites: Excitons, Free Charge, and Subgap States, Phys. Rev. Applied, 2014, 2, 3.
- Stranks, S. D.; Eperon, G. E.; Grancini, G.; Menelaou, C.; Alcocer, M. J. P.; Leijtens, T.; Herz, L. M.; Petrozza, A.; Snaith, H. J. Electron-Hole Diffusion Lengths Exceeding One Micrometer in an Organometal Trihalide Perovskite Absorber, Science, 2013, 342, 341-344
Selected media and press releases:
- Our work on 'Photo-induced halide redistribution in organic–inorganic perovskite films' was featured on the front page of the MIT and DOE websites and highlighted by Nature as well as ScienceDaily, Phys.Org, ChemEurope.com and others (May 2016)
- An article on perovskites in Fast Company based on my TED talk, March 2016
- Sam Stranks selected as a 2016 TED Fellow, December 2015: https://www.eecs.mit.edu/news-events/media/stranks-named-2016-ted-fellow and https://medium.com/ted-fellows/21-rising-stars-to-watch-in-2016-f56c11958963#.jwiik7vao.
- Perovskite Solar Cells Could Beat the Efficiency of Silicon (Scientific American, July 2015): http://www.scientificamerican.com/article/perovskite-solar-cells-could-beat-the-efficiency-of-silicon/
- Press releases on our paper focusing on the microstructure optoelectronic properties of perovskites published in Science, May 2015: http://www.ox.ac.uk/news/2015-05-01-flaw-clue-building-better-solar-cell, http://www.washington.edu/news/2015/04/30/engineering-a-better-solar-cell-uw-research-pinpoints-defects-in-popular-perovskites)
- Perovskites: The Future of PV? (CleanTechnica, June 2014): http://cleantechnica.com/2014/06/11/perovskites-future-pv/
- Revolutionary solar cells double as lasers (Press release about our work led by Cambridge collaborators reporting the first perovskite lasers, March 2014): http://www.cam.ac.uk/research/news/revolutionary-solar-cells-double-as-lasers
- Perspective video. Perovskites: The Emergence of a New Era for Low-Cost, High-Efficiency Solar Cells (J. Phys. Chem. Lett., December 2013): http://pubs.acs.org/page/jpclcd/snaith-video.html
- Creating simpler, cheaper solar cells (Oxford University Science blog about our diffusion paper in Science, November 2013): http://www.ox.ac.uk/news/science-blog/creating-simpler-cheaper-solar-cells