Supporting Information

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1 Supporting Information Low Energy Loss of 0.57 ev and High Efficiency of 8.80% in Porphyrinbased BHJ Solar Cells Maida Vartanian, Rahul Singhal, Pilar de la Cruz, Suhbayan Biswas, Ganesh D. Sharma,,* and Fernando Langa,* Universidad de Castilla-La Mancha. Institute of Nanoscience, Nanotechnology and Molecular Materials (INAMOL), Campus de la Fábrica de Armas, Toledo. Spain. Tel: Department of Physics, Malviya National Institute of Technology (MNIT), Jaipur Department of Physics, The LNM Institute of Information Technology (Deemed University), Rupa ki Nagal, Jamdoli, Jaipur (Raj.) , India 1. General Remarks... S H -NMR, 13 C-NMR, FT-IR and MALDI-TOF MS Spectra... S-3 3. Absorption Spectra in Different Solvents and Film... S-6 4. Electrochemistry Studies... S-7 5. Theoretical Data... S-8 6. Photovoltaic parameters of different 10 devices processed under different conditions... S-9 7. References... S-13

2 1. General Remarks Experimental Conditions. All solvents and reagents were purchased from Aldrich Chemicals. The solvents were used without previous purification. Anhydrous solvents were dried by purification system Pure-Sov 400. Chromatographic purifications were performed using silica gel 60 Merk mesh ASTM. Gel Permeation Chromatograpy (GPC) column was performed using Bio-Beads S-X1 Beads Mesh as stationary phase. Analytical thin-layer chromatography was performed using ALUGRAM SIL G/UV 254 silica gel 60. Nuclear magnetic resonance 1 H-NMR and 13 C-NMR were performed using Bruker Innova 400 Hz. Chemical shifts (δ) values are denoted in ppm. Residual solvent peaks being used as the internal standard (CHCl 3 ; δ = 7.27 ppm). 13 C NMR chemical shifts are reported relative to the solvent residual peaks (CDCl 3, δ = ppm). MALDI-TOF spectra were obtained in VOYAGER DETM STR spectrometry, using dithranol [1,8-dihydroxy-9(10H)-anthracenone] as matrix. Fourier transform infrared spectrophotometer (FT-IR) Thermo Nicolet AVATAR 370 was used with ATR (Attenuated Total Reflection) method, in each case the most characteristic bands are indicated for each compound. Absorption spectra were performed on Shimadzu UV 3600 spectrophotometer. Solutions of different concentration were prepared in CH 2 Cl 2, spectroscopy grade, with absorbance between 0.2 and 0.3 using a 1 cm UV cuvette. Film thickness for UV-Vis were deposited by spin-coating (60 s, 3000 rpm) on cover slips (22x22 mm) from solutions of MV72 in CHCl 3. The thermal stability was evaluated by TGA on a Mettler Toledo TGA/DSC Start e System under nitrogen, with a heating rate of 10 ºC/min. Melting point was recorded using GALLENKAMP Melting Point Apparatus. Electrochemical Measurements: Reduction (E red ) and oxidation potentials (E ox ) were measured by cyclic voltammetry with a potentiostat BAS CV50W in a conventional three-electrode cell equipped with a glassy carbon working electrode, a platinum wire counter electrode, and an Ag/AgNO 3 reference electrode at scan rate of 100 mv/s. The E red and E ox were expressed vs. Fc/Fc + used as external reference. In each case, the measurements were done in a deaerated solution containing 1 mm of a the sample compound in 0.1 M of (n-bu) 4 NClO 4 in o-dcb:acetonitrile (4:1) as an electrolyte solution. Computational Details: Theoretical calculations were carried out within the density functional theory (DFT) framework by using the Gaussian 09, 1 applying density S-1

3 functional theory at the B3LYP level. The basis set of 6-31G* was used in the calculations (Super-computation Service of UCLM). Device fabrication and characterization: Organic solar cells were fabricated using the conventional architecture for ITO/PEDOT:PSS/MV71 or MV71:PC 71 BM/Al. Indium tin oxide (ITO) coated glass substrates were cleaned sequentially by 10 minutes ultrasonication in detergent, deionised water, acetone and isopropyl alcohol followed by drying in a nitrogen flow. The substrates were further dried in ambient conditions. PEDOT:PSS solution was filtered and spin coated onto the pre-cleaned ITO substrates at 3500 rpm for 30 s and then annealed at 120 C for 10 minutes. The blends of MV71 or MV72 and PC 71 BM (different weight ratios of donor and PC71BM, total concentration 16 mg/ml) were dissolved in chlorobenzene (CB). The solutions were spin coated on top of the PEDOT:PSS layer at 2000 rpm for 60 s and the samples were dried in a vacuum oven at 40 C. A thin layer of PFN was spin coated on the top of active layer, which was dissolved in methanol and mixed with acetic acid with a concentration of 0.5 mg/ml and then spin coated at rpm of 2000 to get a thin film of about 10 nm. Finally, the aluminium (Al) electrode was deposited on top of the active layer by thermal evaporation under a vacuum of 10 5 Torr. The current-voltage characteristics of the devices were measured using a computercontrolled Keithley 2400 source meter under stimulated AM1.5 G at an intensity of 100 mw/cm 2 provided by a solar simulator. The incident photon to current efficiency (IPCE) of the devices was measured by illuminating the device through the light source and the monochromator and the resulting current was measured using a Keithley electrometer under short circuit conditions. The hole mobilities of the active layers were determined by fitting the dark current to the model of space charge limited current (SCLC) in the hole only device with the configuration ITO/PEDOT:PSS/active layer/au. The active layers were deposited under the same conditions as for the corresponding solar cells. S-2

4 2. 1 H -NMR, 13 C-NMR, FT-IR and MALDI-TOF MS Spectra Solvent Figure S1 1 H-NMR spectrum of MV72 (400 MHz, CDCl 3 ) S-3

5 Solvent Solvent Figure S2 13 C-NMR spectrum of MV72 (100 MHz, CDCl 3 ) S-4

6 253,10 477,19 Intensity (%) 2122, , , , , , , , , , , ,37 227, Transmittance (%) Wavenumber (cm -1 ) Figure S3. FT-IR spectrum of MV72 (ATR) Mass (m/z) Figure S4. MALDI-TOF MS spectrum of compound MV72. S-5

7 Normalized Absorbance Weight % 2. Thermogravimetric Analysis Temperature ( C) Figure S5 Thermogravimetric analysis of MV72 (at 95 Weight %, T = 354 C) 3. Absorption Spectra in Different Solvents and Film Wavelength (nm) Figure S6 Absorption spectra of MV72 in different solvents (10-6 M), Toluene ( ), Benzonitrile ( ), CH 2 Cl 2 ( ) and in film ( ). S-6

8 I (A) I (A) 4. Electrochemistry Studies 8.0x x x x x x E (V) 1.0x x x x x E (V) Figure S7. Cyclic Voltametry plots of MV72: oxidation (up) and reduction (down) S-7

9 5. Theoretical Data Figure S8. Theoretical optimized geometry of MV71 (up) and MV72 (down) S-8

10 6. Photovoltaic parameters of different 10 devices processed under different conditions Table S1. Photovoltaic parameters of OSCs based on MV71:PC 71 BM (1:2) cast from CB. Device number J SC (ma/cm 2 ) V OC (V) FF PCE (%) S-9

11 Table S2. Photovoltaic parameters of OSCs based on MV71:PC 71 BM (1:2) with SVA treatment. Device number J SC (ma/cm 2 ) V OC (V) FF PCE (%) S-10

12 Table S3. Photovoltaic parameters of OSCs based on MV72:PC 71 BM (1:2) cast from CB. Device number J SC (ma/cm 2 ) V OC (V) FF PCE (%) S-11

13 Table S4. Photovoltaic parameters of OSCs based on MV72:PC 71 BM (1:2) with SVA treatment. Device number J SC (ma/cm 2 ) V OC (V) FF PCE (%) S-12

14 7. References (1) Gaussian 09, Revision A.02, M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R. Cheeseman, G. Scalmani, V. Barone, G. A. Petersson, H. Nakatsuji, X. Li, M. Caricato, A. Marenich, J. Bloino, B. G. Janesko, R. Gomperts, B. Mennucci, H. P. Hratchian, J. V. Ortiz, A. F. Izmaylov, J. L. Sonnenberg, D. Williams- Young, F. Ding, F. Lipparini, F. Egidi, J. Goings, B. Peng, A. Petrone, T. Henderson, D. Ranasinghe, V. G. Zakrzewski, J. Gao, N. Rega, G. Zheng, W. Liang, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven, K. Throssell, J. A. Montgomery, Jr., J. E. Peralta, F. Ogliaro, M. Bearpark, J. J. Heyd, E. Brothers, K. N. Kudin, V. N. Staroverov, T. Keith, R. Kobayashi, J. Normand, K. Raghavachari, A. Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M. Cossi, J. M. Millam, M. Klene, C. Adamo, R. Cammi, J. W. Ochterski, R. L. Martin, K. Morokuma, O. Farkas, J. B. Foresman, and D. J. Fox, Gaussian, Inc., Wallingford CT, S-13