Engineered exciton diffusion length enhances device efficiency in small molecule photovoltaics

Journal article

Sajjad, T, Blaszczyk, Oskar, Jagadamma, Lethy Krishnan, Roland, Thomas J, Chowdhury, Mithun, Ruseckas, Arvydas and Samuel, Ifor DW (2018). Engineered exciton diffusion length enhances device efficiency in small molecule photovoltaics. Journal of Materials Chemistry A. 6 (20), pp. 9445-9450. https://doi.org/10.1039/C8TA01226A
AuthorsSajjad, T, Blaszczyk, Oskar, Jagadamma, Lethy Krishnan, Roland, Thomas J, Chowdhury, Mithun, Ruseckas, Arvydas and Samuel, Ifor DW
Abstract

n organic photovoltaic blends, there is a trade-off between exciton harvesting and charge extraction because of the short exciton diffusion length. Developing a way of increasing exciton diffusion length would overcome this trade-off by enabling efficient light harvesting from large domains. In this work, we engineered (enhanced) both exciton diffusion length and domain size using solvent vapour annealing (SVA). We show that SVA can give a three-fold enhancement in exciton diffusion coefficient (D) and nearly a doubling of exciton diffusion length. It also increases the domain size, leading to enhancement of charge extraction efficiency from 63 to 89%. Usually larger domains would reduce exciton harvesting but this is overcome by the large increase in exciton diffusion, leading to a 20% enhancement in device efficiency.

Year2018
JournalJournal of Materials Chemistry A
Journal citation6 (20), pp. 9445-9450
PublisherRoyal Society of Chemistry (RSC)
ISSN2050-7488
Digital Object Identifier (DOI)https://doi.org/10.1039/C8TA01226A
Publication dates
Print19 Apr 2018
Online19 Apr 2018
Publication process dates
Accepted18 Apr 2018
Deposited12 Feb 2020
Accepted author manuscript
License
File Access Level
Open
Permalink -

https://openresearch.lsbu.ac.uk/item/88z7q

Download files

Accepted author manuscript
Sajjad_2018_Engineered_exciton_JMCA_AAM.pdf
License: CC BY 4.0
File access level: Open

  • 97
    total views
  • 198
    total downloads
  • 1
    views this month
  • 1
    downloads this month

Export as

Related outputs

Phosphinecarboxamide based InZnP QDs – an air tolerant route to luminescent III–V semiconductors
Wang, Y., Howley, J., Faria, E.N., Huang, C., Carter-Searjeant, S., Fairclough, S., Kirkland, A., Davis, J.J., Naz, F., Sajjad, T., Goicoechea, J.M. and Mark Green (2023). Phosphinecarboxamide based InZnP QDs – an air tolerant route to luminescent III–V semiconductors. Nanoscale Horizons. 8, pp. 1411-1416. https://doi.org/10.1039/d3nh00162h
Outstanding visible light photocatalysis by nano-TiO2 hybrids with nitrogen-doped carbon quantum dots and/or reduced graphene oxide
Baragau, I., Buckeridge, J., Nguyen, K., Heil, T, Sajjad, T., Thomson, S., Rennie, A., Morgan, D., Power, N., Nicolae, S., Titirici, M., Dunn, S. and Kellici, S. (2023). Outstanding visible light photocatalysis by nano-TiO2 hybrids with nitrogen-doped carbon quantum dots and/or reduced graphene oxide. Journal of Materials Chemistry A. https://doi.org/10.1039/D2TA09586F
3D printed SrNbO2N photocatalyst for degradation of organic pollutants in water
Iborra-Torres, A., Husˇ, M., Nguyen, K., Vamvakeros, A., Sajjad, T., Dunn, S., Mertens, M., Jacques, S., Beale, A., Likozar, B., Hyett, G., Kellici, S. and Middelkoop, V. (2023). 3D printed SrNbO2N photocatalyst for degradation of organic pollutants in water. Materials Advances. https://doi.org/10.1039/D2MA01076C
Synthesis and optical characterization of lead-free phenylenediammonium bismuth halide perovskites: a long charge carrier lifetime in phenylenediammonium bismuth iodide
Siddique, Z, Payne, J. L, Mica, N, Cordes, D. B, Slawin, A. M. Z, Samuel,I. D. W, Iqbal, A, Irvine, J. T. S and Sajjad, T. (2023). Synthesis and optical characterization of lead-free phenylenediammonium bismuth halide perovskites: a long charge carrier lifetime in phenylenediammonium bismuth iodide. Journal of Materials Chemistry C. 11 (1), pp. 223-234. https://doi.org/10.1039/d2tc02601e
Investigating the effect of N-doping on carbon quantum dots structure, optical properties and metal ion screening.
Nguyen, K.G., Baragau, I-A., Gromicova, R., Nicolaev, A., Thomson, S. A J, Rennie, A., Power, N. P, Sajjad, T. and Kellici, S. (2022). Investigating the effect of N-doping on carbon quantum dots structure, optical properties and metal ion screening. Scientific Reports. 12 (1), p. 13806. https://doi.org/10.1038/s41598-022-16893-x
A Multifaceted Ferrocene Interlayer for Highly Stable and Efficient Lithium Doped Spiro‐OMeTAD‐based Perovskite Solar Cells
Webb, T., Liu, X., Westbrook, R.J.E., Kern, S., Sajjad, M.T., Jenatsch, S., Jayawardena, K. D. G. Imalka, Perera, W. H.K., Marko, I.P., Sathasivam, S., Li, B., Yavari, M., Scurr, D.J., Alexander, M.R., Macdonald, T.J., Haque, S.A., Sweeney, S.J. and Zhang, W. (2022). A Multifaceted Ferrocene Interlayer for Highly Stable and Efficient Lithium Doped Spiro‐OMeTAD‐based Perovskite Solar Cells. Advanced Energy Materials. https://doi.org/10.1002/aenm.202200666
Recent Progress in Micro‐LED‐Based Display Technologies
Sajjad, T., Sajjad, M.T., Johar, M.A., Hernández‐Gutiérrez, C.A., Usman, M. and Łepkowski, S. P. (2022). Recent Progress in Micro‐LED‐Based Display Technologies. Laser & Photonics Reviews. https://doi.org/10.1002/lpor.202100427
Development of Quantum Dot (QD) Based Color Converters for Multicolor Display.
Sajjad, T., Bansal, A.K., Antolini, F., Preis, E., Stroea, L., Toffanin, S., Muccini, M., Ortolani, L., Migliori, A., Allard, S., Scherf, U. and Samuel, I. (2021). Development of Quantum Dot (QD) Based Color Converters for Multicolor Display. Nanomaterials. 11 (5). https://doi.org/nano11051089
Direct Growth of Vertically Aligned Carbon Nanotubes onto Transparent Conductive Oxide Glass for Enhanced Charge Extraction in Perovskite Solar Cells
Ferguson, V., Li, B., Tas, M., Webb, Thomas, Sajjad, T., Thomson, Stuart A. J., Wu, Zhiheng, Shen, Yonglong, Shao, Guosheng, Anguita, José V., Silva, S. and Zhang, W. (2020). Direct Growth of Vertically Aligned Carbon Nanotubes onto Transparent Conductive Oxide Glass for Enhanced Charge Extraction in Perovskite Solar Cells. Advanced Materials Interfaces. 7 (21), p. 2001121. https://doi.org/10.1002/admi.202001121
Reduced Bilateral Recombination by Functional Molecular Interface Engineering for Efficient Inverted Perovskite Solar Cells
Sajjad, M. T., Li, B., Xiang, Y., Imalka Jayawardena, K.D.G, Luo, D., Wang, Z., Yang, X., Watts, J.F., Hinder, S., Webb, T., Luo, H., Marko, I., Li, H., Thomsen, S.J.A, Zhu, R., Shao, G., Sweeney, S.J., Silva, S.R.P and Zhang, W. (2020). Reduced Bilateral Recombination by Functional Molecular Interface Engineering for Efficient Inverted Perovskite Solar Cells. Nano Energy. 78, p. 105249. https://doi.org/10.1016/j.nanoen.2020.105249
Long-range Exciton Diffusion in Non-Fullerene Acceptors and Coarse Bulk Heterojunctions Enable Highly Efficient Organic Photovoltaics
Sajjad, T. M. (2020). Long-range Exciton Diffusion in Non-Fullerene Acceptors and Coarse Bulk Heterojunctions Enable Highly Efficient Organic Photovoltaics. Journal of Materials Chemistry A. https://doi.org/10.1039/D0TA06017H
Enhancing Exciton Diffusion Length Provides New Opportunities for Organic Photovoltaics
Sajjad, M. T., Ruseckas, A. and Samuel, D.W. (2020). Enhancing Exciton Diffusion Length Provides New Opportunities for Organic Photovoltaics. Matter. 3 (5), pp. 341-354. https://doi.org/10.1016/j.matt.2020.06.028
Enhanced exciton harvesting in a planar heterojunction organic photovoltaic device by solvent vapor annealing
Zhang, Yiwei, Sajjad, T, Blaszczyk, Oskar, Ruseckas, Arvydas, Serrano, Luis A, Cooke, Graeme and Samuel, Ifor DW (2019). Enhanced exciton harvesting in a planar heterojunction organic photovoltaic device by solvent vapor annealing. Organic Electronics. 70, pp. 162-166. https://doi.org/10.1016/j.orgel.2019.03.014
Efficient indoor pin hybrid perovskite solar cells using low temperature solution processed NiO as hole extraction layers
Jagadamma, Lethy Krishnan, Blaszczyk, Oskar, Sajjad, T., Ruseckas, Arvydas and Samuel, Ifor DW (2019). Efficient indoor pin hybrid perovskite solar cells using low temperature solution processed NiO as hole extraction layers. Solar Energy Materials and Solar Cells. 201, pp. 110071-110071. https://doi.org/10.1016/j.solmat.2019.110071
Large crystalline domains and enhanced exciton diffusion length enable efficient organic solar cells
Zhang, Y., Sajjad, T., Blaszczyk, O., Parnell, A.J, Ruseckas, A., Serrano, L.A, Cooke, G. and Samuel, I.D.W (2019). Large crystalline domains and enhanced exciton diffusion length enable efficient organic solar cells. Chemistry of Materials. 31 (17), pp. 6548-6557. https://doi.org/10.1021/acs.chemmater.8b05293
Tailoring exciton diffusion and domain size in photovoltaic small molecules by annealing
Sajjad, T., Zhang, Y., Geraghty, P.B., Mitchell, V.D., Ruseckas, A., Blaszczyk, O., Jones, D.J. and Samuel, I.D.W. (2019). Tailoring exciton diffusion and domain size in photovoltaic small molecules by annealing. Journal of Materials Chemistry C. 7 (26), pp. 7922-7928. https://doi.org/10.1039/C9TC00951E
Highly efficient fullerene and non-fullerene based ternary organic solar cells incorporating a new tetrathiocin-cored semiconductor
Jagadamma, LK, Taylor, RGD, Kanibolotsky, AL, Sajjad, T, Wright, IA, Horton, PN, Coles, SJ, Samuel, IDW and Skabara, Peter J (2019). Highly efficient fullerene and non-fullerene based ternary organic solar cells incorporating a new tetrathiocin-cored semiconductor. Sustainable Energy & Fuels. 3 (8), pp. 2087-2099. https://doi.org/10.1039/C9SE00343F
Interface limited hole extraction from methylammonium lead iodide films
Blaszczyk, Oskar, Jagadamma, Lethy Krishnan, Ruseckas, Arvydas, Sajjad, T, Zhang, Yiwei and Samuel, Ifor DW (2019). Interface limited hole extraction from methylammonium lead iodide films. Materials Horizons. https://doi.org/https://www.doi.org/10.1039/c9mh01517e
CuSCN Nanowires as Electrodes for p-Type Quantum Dot Sensitized Solar Cells: Charge Transfer Dynamics and Alumina Passivation
Sajjad, Muhammad T, Sajjad, T, Park, Jinhyung, Gaboriau, Dorian, Harwell, Jonathon R, Odobel, Fabrice, Reiss, Peter, Samuel, Ifor DW and Aldakov, Dmitry (2018). CuSCN Nanowires as Electrodes for p-Type Quantum Dot Sensitized Solar Cells: Charge Transfer Dynamics and Alumina Passivation. The Journal of Physical Chemistry C. 122 (9), pp. 5161-5170. https://doi.org/10.1021/acs.jpcc.7b12619
Improved efficiency of PbS quantum dot sensitized NiO photocathodes with naphthalene diimide electron acceptor bound to the surface of the nanocrystals
Raissi, Mahfoudh, Sajjad, T, Farré, Yoann, Roland, Thomas J, Ruseckas, Arvydas, Samuel, Ifor DW and Odobel, Fabrice (2018). Improved efficiency of PbS quantum dot sensitized NiO photocathodes with naphthalene diimide electron acceptor bound to the surface of the nanocrystals. Solar Energy Materials and Solar Cells. 181, pp. 71-76. https://doi.org/10.1016/j.solmat.2017.12.029
In situ formation and photo patterning of emissive quantum dots in small organic molecules
Bansal, Ashu K, Sajjad, T, Antolini, Francesco, Stroea, Lenuta, Gečys, Paulius, Raciukaitis, Gediminas, André, Pascal, Hirzer, Andreas, Schmidt, Volker and Ortolani, Luca (2018). In situ formation and photo patterning of emissive quantum dots in small organic molecules. Nanoscale. 7 (25), pp. 11163-11172. https://doi.org/10.1039/C5NR01401H
pH-Induced transformation of ligated Au 25 to brighter Au 23 nanoclusters
Waszkielewicz, Magdalena, Olesiak-Banska, Joanna, Comby-Zerbino, Clothilde, Bertorelle, Franck, Dagany, Xavier, Bansal, Ashu K, Sajjad, T, Samuel, Ifor DW, Sanader, Zeljka and Rozycka, Miroslawa (2018). pH-Induced transformation of ligated Au 25 to brighter Au 23 nanoclusters. Nanoscale. 10 (24), pp. 11335-11341. https://doi.org/10.1039/C8NR00660A
Role of lattice distortion and A site cation in the phase transitions of methylammonium lead halide perovskites
Harwell, Jonathon R, Payne, Julia L, Sajjad, T., Heutz, Frank JL, Dawson, Daniel M, Whitfield, Pamela S, Irvine, John TS, Samuel, Ifor DW and Carpenter, Michael A (2018). Role of lattice distortion and A site cation in the phase transitions of methylammonium lead halide perovskites. Physical Review Materials. 2 (6), pp. 065404-065404. https://doi.org/https://www.doi.org/10.1103/PhysRevMaterials.2.065404
Triptycene as a Supramolecular Additive in PTB7: PCBM blends and its Influence on Photovoltaic Properties
Krishnan Jagadamma, Lethy, McCarron, Liam J, Wiles, Alan A, Savikhin, Victoria, Sajjad, T., Yazdani, Mahdieh, Rotello, Vincent M, Toney, Michael F, Cooke, Graeme and Samuel, Ifor DW (2018). Triptycene as a Supramolecular Additive in PTB7: PCBM blends and its Influence on Photovoltaic Properties. ACS applied materials & interfaces. 10 (29), pp. 24665-24678. https://doi.org/https://www.doi.org/10.1021/acsami.8b03114
Tuning the Exciton Diffusion Coefficient of Polyfluorene Based Semiconducting Polymers
Sajjad, T., Ward, A. J, Ruseckas, A., Bansal, A. K, Allard, S., Scherf, U. and Samuel, I. DW (2018). Tuning the Exciton Diffusion Coefficient of Polyfluorene Based Semiconducting Polymers. physica status solidi (RRL)–Rapid Research Letters. 13 (3), pp. 1800500-1800500. https://doi.org/https://www.doi.org/10.1002/pssr.201800500
A saturated red color converter for visible light communication using a blend of star-shaped organic semiconductors
Sajjad, T, Manousiadis, PP, Orofino, Clara, Kanibolotsky, AL, Findlay, Neil J, Rajbhandari, Sujan, Vithanage, DA, Chun, Hyunchae, Faulkner, GE and O’Brien, DC (2017). A saturated red color converter for visible light communication using a blend of star-shaped organic semiconductors. Applied Physics Letters. 110 (1), pp. 013302-013302. https://doi.org/10.1063/1.4971823
Correlating photovoltaic properties of PTB7-Th:PC71BM blend to photophysics and microstructure as a function of thermal annealing
Jagadamma, Lethy Krishnan, Sajjad, Muhammad T, Savikhin, Victoria, Toney, Michael F, Samuel, Ifor DW and Sajjad, T (2017). Correlating photovoltaic properties of PTB7-Th:PC71BM blend to photophysics and microstructure as a function of thermal annealing. Journal of Materials Chemistry A. 5 (28), pp. 14646-14657. https://doi.org/10.1039/C7TA03144K
Exciton diffusion length and charge extraction yield in organic bilayer solar cells
Siegmund, B., Sajjad, T, Widmer, J., Ray, D., Koerner, C., Riede, M., Leo, K., Samuel, I.D.W. and Vandewal, K. (2017). Exciton diffusion length and charge extraction yield in organic bilayer solar cells. Advanced Materials. 29 (12), pp. 1604424-1604424. https://doi.org/10.1002/adma.201604424
Narrow-band anisotropic electronic structure of ReS2
Biswas, D, Ganose, Alex M, Yano, R, Riley, JM, Bawden, L, Clark, OJ, Feng, J, Collins-Mcintyre, L, Sajjad, T and Meevasana, W (2017). Narrow-band anisotropic electronic structure of ReS2. Physical Review B. 96 (8). https://doi.org/10.1103/PhysRevB.96.085205
Novel 4, 8-benzobisthiazole copolymers and their field-effect transistor and photovoltaic applications
Conboy, G., Taylor, R.G.D., Findlay, N.J., Kanibolotsky, A.L., Inigo, A.R., Ghosh, S.S., Ebenhoch, B., Jagadamma, L.K., Thalluri, G.K.V.V. and Sajjad, T. (2017). Novel 4, 8-benzobisthiazole copolymers and their field-effect transistor and photovoltaic applications. Journal of Materials Chemistry C. 5 (45), pp. 11927-11936. https://doi.org/10.1039/C7TC03959J
Polymer colour converter with very high modulation bandwidth for visible light communications
Vithanage, DA, Kanibolotsky, AL, Rajbhandari, S, Manousiadis, PP, Sajjad, T., Chun, H, Faulkner, GE, O'Brien, DC, Skabara, PJ, Samuel, IDW and Turnbull, GA (2017). Polymer colour converter with very high modulation bandwidth for visible light communications. Journal of Materials Chemistry C. 5 (35), pp. 8916-8920. https://doi.org/10.1039/c7tc03787b
Size dependence of efficiency of PbS quantum dots in NiO-based dye sensitised solar cells and mechanistic charge transfer investigation
Raissi, Mahfoudh, Sajjad, T., Pellegrin, Yann, Roland, Thomas Jean, Jobic, Stéphane, Boujtita, Mohammed, Ruseckas, Arvydas, Samuel, Ifor DW and Odobel, Fabrice (2017). Size dependence of efficiency of PbS quantum dots in NiO-based dye sensitised solar cells and mechanistic charge transfer investigation. Nanoscale. 9 (40), pp. 15566-15575. https://doi.org/https://www.doi.org/10.1039/C7NR03698A
Tuning crystalline ordering by annealing and additives to study its effect on exciton diffusion in a polyalkylthiophene copolymer
Chowdhury, Mithun, Sajjad, T., Savikhin, Victoria, Hergué, Noémie, Sutija, Karina B, Oosterhout, Stefan D, Toney, Michael F, Dubois, Philippe, Ruseckas, Arvydas and Samuel, Ifor DW (2017). Tuning crystalline ordering by annealing and additives to study its effect on exciton diffusion in a polyalkylthiophene copolymer. Physical Chemistry Chemical Physics. 19 (19), pp. 12441-12451. https://doi.org/https://www.doi.org/10.1039/C7CP00877E
BODIPY star-shaped molecules as solid state colour converters for visible light communications
Vithanage, DA, Manousiadis, PP, Sajjad, T, Rajbhandari, Sujan, Chun, Hyunchae, Orofino, Clara, Cortizo-Lacalle, Diego, Kanibolotsky, AL, Faulkner, Grahame and Findlay, NJ (2016). BODIPY star-shaped molecules as solid state colour converters for visible light communications. Applied Physics Letters. 109 (1), pp. 013302-013302. https://doi.org/10.1063/1.4953789
Controlling the emission efficiency of blue-green iridium (iii) phosphorescent emitters and applications in solution-processed organic light-emitting diodes
Sajjad, T, Sharma, Nidhi, Pal, Amlan K, Hasan, Kamrul, Xie, Guohua, Kölln, Lisa S, Hanan, Garry S, Samuel, Ifor DW and Zysman-Colman, Eli (2016). Controlling the emission efficiency of blue-green iridium (iii) phosphorescent emitters and applications in solution-processed organic light-emitting diodes. Journal of Materials Chemistry C. 4 (38), pp. 8939-8946. https://doi.org/10.1039/C6TC02909D
Efficient eco-friendly inverted quantum dot sensitized solar cells
Park, J., Sajjad, T, Jouneau, P-H., Ruseckas, A., Faure-Vincent, J., Samuel, I.D.W., Reiss, P. and Aldakov, D. (2016). Efficient eco-friendly inverted quantum dot sensitized solar cells. Journal of Materials Chemistry A. 4 (3), pp. 827-837. https://doi.org/10.1039/C5TA06769C
Controlling exciton diffusion and fullerene distribution in photovoltaic blends by side chain modification
Sajjad, T, Ward, Alexander J, Kästner, Christian, Ruseckas, Arvydas, Hoppe, Harald and Samuel, Ifor DW (2015). Controlling exciton diffusion and fullerene distribution in photovoltaic blends by side chain modification. The journal of physical chemistry letters. 6 (15), pp. 3054-3060. https://doi.org/10.1021/acs.jpclett.5b01059
Fluorescent Red-Emitting BODIPY Oligofluorene Star-Shaped Molecules as a Color Converter Material for Visible Light Communications
Sajjad, T, Manousiadis, Pavlos P, Orofino, Clara, Cortizo-Lacalle, Diego, Kanibolotsky, Alexander L, Rajbhandari, Sujan, Amarasinghe, Dimali, Chun, Hyunchae, Faulkner, Grahame and O’Brien, Dominic C (2015). Fluorescent Red-Emitting BODIPY Oligofluorene Star-Shaped Molecules as a Color Converter Material for Visible Light Communications. Advanced optical materials. 3 (4), pp. 536-540. https://doi.org/10.1002/adom.201400424
Mercaptophosphonic acids as efficient linkers in quantum dot sensitized solar cells
Aldakov, D, Sajjad, T, Ivanova, V, Bansal, AK, Park, J, Reiss, P and Samuel, IDW (2015). Mercaptophosphonic acids as efficient linkers in quantum dot sensitized solar cells. Journal of Materials Chemistry A. 3 (37), pp. 19050-19060. https://doi.org/10.1039/C5TA04021C
Novel fast color-converter for visible light communication using a blend of conjugated polymers
Sajjad, T, Manousiadis, Pavlos P, Chun, Hyunchae, Vithanage, Dimali A, Rajbhandari, Sujan, Kanibolotsky, Alexander L, Faulkner, Grahame, O’Brien, Dominic, Skabara, Peter J and Samuel, Ifor DW (2015). Novel fast color-converter for visible light communication using a blend of conjugated polymers. Acs Photonics. 2 (2), pp. 194-199. https://doi.org/10.1021/ph500451y
Photophysical and structural characterisation of in situ formed quantum dots
Bansal, AK, Antolini, F, Sajjad, T, Stroea, L, Mazzaro, R, Ramkumar, SG, Kass, K-J, Allard, S, Scherf, U and Samuel, IDW (2014). Photophysical and structural characterisation of in situ formed quantum dots. Physical Chemistry Chemical Physics. 16 (20), pp. 9556-9564. https://doi.org/https://www.doi.org/10.1039/C4CP00727A
Synthesis and properties of novel star-shaped oligofluorene conjugated systems with BODIPY cores
Orofino-Pena, Clara, Cortizo-Lacalle, Diego, Cameron, Joseph, Sajjad, T., Manousiadis, Pavlos P, Findlay, Neil J, Kanibolotsky, Alexander L, Amarasinghe, Dimali, Skabara, Peter J and Tuttle, Tell (2014). Synthesis and properties of novel star-shaped oligofluorene conjugated systems with BODIPY cores. Beilstein journal of organic chemistry. 10, pp. 2704-2714. https://doi.org/https://www.doi.org/10.3762/bjoc.10.285
Measurement of a reaction-diffusion crossover in exciton-exciton recombination inside carbon nanotubes using femtosecond optical absorption
Allam, J, Sajjad, T, Sutton, R, Litvinenko, K, Wang, Zilong, Siddique, S, Yang, Q-H, Loh, Wei H and Brown, T (2013). Measurement of a reaction-diffusion crossover in exciton-exciton recombination inside carbon nanotubes using femtosecond optical absorption. Physical review letters. 111 (19), pp. 197401-197401. https://doi.org/10.1103/PhysRevLett.111.197401