January 2011 - October 2012
Department of Physics
Imperial College London
Development of methods to simulate the process of charge separation at molecular heterojunctions
Photovoltaic devices based on organic semiconductor materials are currently one of the most interesting options for long term reductions in the cost of photovoltaic electricity. Practical application of the so-called organic photovoltaic (OPV) technology requires improved performance, both in terms of solar-to-electric power conversion efficiency and in terms of module lifetime. A key determinant of the achievable power conversion efficiency is the efficiency of photoinduced charge separation and the energetic cost of this process. However, until now there is no agreed picture of the microscopic physical mechanism of charge separation, nor of the quantitative effect of the different factors (energetic and structural) that control this process. The problem is complicated by the inherent disorder at the charge separating interface. In this project we plan to develop methods to simulate the process of charge separation at molecular heterojunctions allowing for the disordered nature of the materials. Methods will be applied to a variety of photovoltaic heterojunctions, such as organic binaries and organic-inorganic heterojunctions. We are also interested in determining the potential of novel, molecular photovoltaic materials to contribute to clean electricity generation.
- Jenny Nelson “The Physics of Solar Cells“ (Imperial College Press, London) 2003 (ISBN 1-86094-349-7).
- Christoph Brabec, Iain McCulloch and Jenny Nelson “Determination and control of microstructure in organic photovoltaic devices“, Chapter in Functional Supramolecular Architectures, P. Samori and F. Cacialli (Eds.) (Wiley-VCH) In press 2010.
- Jessica Benson-Smith and Jenny Nelson “Organic donor-acceptor heterojunction solar cells“ Chapter 7 in Nanostructured and Photoelectrochemical Systems for Solar Photon Conversion, Mary D. Archer and Arthur J. Nozik, Eds., (Imperial College Press, London) 2008 (ISBN-10 1 86094 255 5).
- Jenny Nelson “Organic and Plastic Solar Cells“, Chapter in Practical Handbook of Photovoltaics: Fundamentals and Applications, Tomas Markvart and Luis Castaner, (Elsevier) 2003. (ISBN 1-85617-390-9). Reprinted in a selected edition “Solar Cells” (Elsevier) 2004.
- Jenny Nelson “Solar Cell Efficiency: Routes to increasing the limiting efficiency of solar cells“ Sci-Notes: Solar Energy, 1(2) (2002) (ISSN 1472-8125)
- Jenny Nelson “Charge transport in Dye Sensitised systems” Chapter in Semiconductor Electrodes and Photoelectrochemistry, Stuart Licht, Ed., Volume 6 of Encyclopaedia of Electrochemistry, Allen J. Bard and Prof. Stratmann, Series Eds., (WILEY-VCH,) 2002. (ISBN 3-527-30398-7).
- Jenny Nelson “Electronic states and optical properties of quantum wells“ Chapter in Quantum Semiconductor Structures, K. W. J. Barnham & D. Vvedenski, Eds., (Cambridge University Press, Cambridge) 2001 (ISBN 0 521 59103 1).
- Jenny Nelson “Quantum Well Solar Cells“, Chapter 10 in Clean Electricity from Photovoltaics, Mary D. Archer and Robert Hill, Eds., (Imperial College Press, London) 2001 (ISBN 1 86094 161 3).
Selected Publications in Peer Review Journals (> 180 papers in total, h-index = 45)
- A.A. Guilbert, L.X. Reynolds, A. Bruno, A. Maclachlan, S.P. King, M.A. Faist, E. Pires, J.E. Macdonald, N. Stingelin, S.A. Haque, J. Nelson: Effect of Multiple Adduct Fullerenes on Microstructure and Phase Behaviour of P3HT:Fullerene Blend Films for Organic Solar Cells. Acs Nano, 2012; 6 (5): 3868-3875. http://dx.doi.org/10.1021/nn204996w
- M.M. Voigt, R.C.I. Mackenzie, S.P. King, C. P. Yau, P. Atienzar, J. Dane, P. E. Keivanidis, I. Zadrazil, D. D.C. Bradley, J. Nelson: Gravure printing inverted organic solar cells: The influence of ink properties on film quality and device performance. Sol Energ Mat Sol C, 2012; 105: 77-85.
- Y.W. Soon, T.M. Clarke, J. Kirkpatrick, J. Nelson,, J.R. Durrant: Energy versus electron transfer in organic solar cells: a comparison of the photophysics of two indenofluorene: fullerene blend films J Chem Sci, 2011; 2 (6): 1111-1120
- R.C.I. MacKenzie, T. Kirchartz, G.F.A. Dibb, J. Nelson,: Modeling Nongeminate Recombination in P3HT:PCBM Solar Cells J Phys Chem C, 2011; 115 (19): 9806-9813
- T. Agostinelli, J. Rawle, O. Bikondoa, D.D.C. Bradley, J. Nelson, J.E. Macdonald: Real-Time Investigation of Crystallization and Phase-Segregation Dynamics in P3HT:PCBM Solar Cells During Thermal Annealing Adv Funct Mater, 2011; 21 (9): 1701-1708
- T.A Ferenczi, C. Mueller, D.D. Bradley, P. Smith, J. Nelson, N. Stingelin: Organic Semiconductor:Insulator Polymer Ternary Blends for Photovoltaics. Adv Mater, 2011: http://dx.doi.org/10.1002/adma.201102100 (in press)
- T. Agostinelli, T.A.M. Ferenczi, S. Foster, A. Ballantyne, M. Hampton, S. Lilliu, J.E. Macdonald, N. Stingelin, J. Nelson: The Role of Alkane Dithiols in Controlling Polymer Crystallization in Small Band Gap Polymer:Fullerene Solar Cells J Polym Sci Pol Phys, 2011; 49 (10): 717-724
- C. Muller, T. A. M. Ferenczi, M. Campoy-Quiles, J. M. Frost, D. D. C. Bradley, P. Smith, N. Stingelin-Stutzmann, and J. Nelson (corresponding author), Binary organic photovoltaic blends: A simple rationale for optimum compositions, Advanced Materials 20, 3510 (2008).
- M. Campoy-Quiles (PDRA of JN), T. Ferenczi, T. Agostinelli, P. G. Etchegoin, Y. Kim, T. D. Anthopoulos, P. N. Stavrinou, D. D. C. Bradley, and J. Nelson (corresponding author), Morphology evolution via self-organization and lateral and vertical diffusion in polymer: fullerene solar cell blends, Nature Materials 7, 158 (2008).
- J. Kirkpatrick (PhD student of JN), V. Marcon, J. Nelson, K. Kremer, and D. Andrienko, Charge mobility of discotic mesophases: A multiscale quantum and classical study, Physical Review Letters 98, (2007).
- J. J. Benson-Smith (PhD student of JN), L. Goris, K. Vandewal, K. Haenen, J. V. Manca, D. Vanderzande, D. D. C. Bradley, and J. Nelson (corresponding author) , Formation of a ground-state charge-transfer complex in polyfluorene/[6,6]-phenyl-C-61 butyric acid methyl ester (PCBM) blend films and its role in the function of polymer/PCBM solar cells, Advanced Functional Materials 17, 451 (2007).
- P. Ravirajan (PhD student of JN) , A. M. Peiro, M. K. Nazeeruddin, M. Graetzel, D. D. C. Bradley, J. R. Durrant, and J. Nelson (corresponding author), Hybrid polymer/zinc oxide photovoltaic devices with vertically oriented ZnO nanorods and an amphiphilic molecular interface layer, Journal of Physical Chemistry B 110, 7635 (2006).
- Y. Kim, S. Cook, S. M. Tuladhar, S. A. Choulis, J. Nelson (corresponding author), J. R. Durrant, D. D. C. Bradley, M. Giles, I. McCulloch, C. S. Ha, and M. Ree, A strong regioregularity effect in self-organizing conjugated polymer films and high-efficiency polythiophene: fullerene solar cells, Nature Materials 5, 197 (2006).
- S. M. Tuladhar (PhD student of JN), D. Poplavskyy, S. A. Choulis, J. R. Durrant, D. D. C. Bradley, and J. Nelson (PI corresponding author), Ambipolar charge transport in films of methanofullerene and poly-(phenylenevinylene)/methanofullerene blends, Advanced Functional Materials 15, 1171 (2005).
- J. Nelson (sole author), Diffusion-limited recombination in polymer-fullerene blends and its influence on photocurrent collection, Physical Review B 67, (2003).
- J. Nelson (lead and corresponding author), S. A. Haque, D. R. Klug and J. R. Durrant, Trap-limited recombination in dye-sensitized nanocrystalline metal oxide electrodes, Physical Review B 63, 205321 (2001).
- J. Nelson (sole author), Continuous-time random-walk model of electron transport in nanocrystalline TiO2 electrodes, Physical Review B 59, 15374 (1999).