The additive substituent effect of phenylmercapto derivatives of corannulene are investigated by spectroscopic, electrochemical, and computational techniques. The per-substituted phenylmercaptocorannulene is incorporated as a replacement for [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) in a photovoltaic device.
Keywords:
photovoltaic; electrochemistry; corannulene; photochemistry
| Compound | λa / nm (log ε [M-1 cm-1]) | λf / nm | λs = λf - λa / nm | Фf | [ns] | λp / nm |
|---|---|---|---|---|---|---|
| 1 | 196 (4.9), 221 (4.7), 252 (λmax) (4.9), 286 (λexc) (4.6) |
348, 422 (λmax) | 62 | 0.04 | 10.0 | 483, 515 (λmax), 553, 598 |
| 2b | 194 (4.7), 250 (4.7), 255 (λmax) (4.7), 292 (λexc) (4.4) |
356, 448 (λmax) | 64 | 0.05 | 1.1 | 566 (λmax) |
| 3b | 254 (λmax) (4.6), 278 (4.3), 295 (λexc) (4.3) |
365, 456 (λmax) | 70 | 0.04 | 5.6 | 535, 559 (λmax) |
| 4b | 200 (4.8), 256 (4.8), 263 (λmax) (4.8), 302 (λexc) (4.4) |
354, 460 (λmax) | 52 | 0.20 | 1.5 | 565 (λmax) |
| 5b | 260 (λmax) (4.8), 310 (λexc) (4.3) | 380, 496 (λmax) | 70 | 0.02 | 1.7 | 555, 604 (λmax), 652 |
| 6b | 252 (λmax) (4.9), 344 (λexc) (4.5) | 405, 492 (λmax) | 61 | 0.01 | 0.8 | 560, 600 (λmax), 645 |
| 7b | 235 (5.0), 260 (λmax) (5.0), 417 (λexc) (4.4) |
- | - | 0.00 | - | 725 (λmax) |
| 7b* | 265 (λmax) (3.9), 316 (3.8), 384 (λexc)(3.7) |
433 (λmax), 531 | 49 | 0.01 | 6.0 | 728 (λmax) |
| Compound | RedCVa a Cyclic voltammetry: 1 mmol L-1 compound 1-7b* and 0.07 mol L-1 tetrabutylammonium hexafluorophosphate (TBAPF6) in tetrahydrofuran (THF; 298 K). Electrodes: working, glassy carbon; reference, Ag/Ag+ in acetonitrile (ACN); counter, platinum wire. Scan rate = 0.1 V s-1. All E1/2 potentials are direct averages of the cathodic and anodic peak potentials. Internal standard: ferrocinium/ferrocene couple (+0.085 V for THF);27 / V | OxCV / V | IPCV / eV | ΔIP / eV |
|---|---|---|---|---|
| 1 | –2.45 [–2.49]b b Values in brackets are B97D/Def2-TZVPP(THF)E° = -ΔG/nF + Eref, n = 1, F = 1 eV, corrected to Ag/AgCl electrode, 4.52; | +1.57irrev,2,27 | 7.96 [7.92]c | 0.41 |
| 2b | –2.43 [–2.34]b b Values in brackets are B97D/Def2-TZVPP(THF)E° = -ΔG/nF + Eref, n = 1, F = 1 eV, corrected to Ag/AgCl electrode, 4.52; | +1.25-1.35irrev | 7.33 [7.64]c c ΔSCF/CBS-4M IP; | 0.67 |
| 3b | –2.09 [–2.15]b b Values in brackets are B97D/Def2-TZVPP(THF)E° = -ΔG/nF + Eref, n = 1, F = 1 eV, corrected to Ag/AgCl electrode, 4.52; | +1.05-1.15irrev | 7.11 [7.38]c c ΔSCF/CBS-4M IP; | 0.41 |
| 4b | –2.28 [–2.17, –2.22, –2.12]b b Values in brackets are B97D/Def2-TZVPP(THF)E° = -ΔG/nF + Eref, n = 1, F = 1 eV, corrected to Ag/AgCl electrode, 4.52; ,d d for 4b and 6b values are ranked in accordance with the relative energy ordering of the isomers. irrev: irreversible. | +1.15-1.25irrev | 7.68 [7.77, 7.18, 7.75]c c ΔSCF/CBS-4M IP; ,d d for 4b and 6b values are ranked in accordance with the relative energy ordering of the isomers. irrev: irreversible. | - |
| 5b | –1.95 [–1.85]b b Values in brackets are B97D/Def2-TZVPP(THF)E° = -ΔG/nF + Eref, n = 1, F = 1 eV, corrected to Ag/AgCl electrode, 4.52; | +1.35-1.45irrev | 7.73 [8.28]c c ΔSCF/CBS-4M IP; | 0.37 |
| 6b | –1.92 [–2.02, –1.90],b b Values in brackets are B97D/Def2-TZVPP(THF)E° = -ΔG/nF + Eref, n = 1, F = 1 eV, corrected to Ag/AgCl electrode, 4.52; ,d d for 4b and 6b values are ranked in accordance with the relative energy ordering of the isomers. irrev: irreversible. –2.53 | +1.4-1.5irrev | 7.64 | 0.36 |
| 7b | –1.49 [–1.55],b b Values in brackets are B97D/Def2-TZVPP(THF)E° = -ΔG/nF + Eref, n = 1, F = 1 eV, corrected to Ag/AgCl electrode, 4.52; –2.02, –2.58 | +0.6-0.7 | 6.25 | - |
| 7b* | –2.00, –2.74 | +1.1-1.2irrev | 7.24 | - |
| 7b:P3HT | VOC / V | JSC / (mA cm-2) |
FF | η / % |
|---|---|---|---|---|
| 1:1 | 0.626 | 0.95 | 0.33 | 0.20 |
| 2:3 | 0.544 | 1.27 | 0.35 | 0.24 |
| 3:2 | 0.644 | 1.38 | 0.34 | 0.30 |
