Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes
Reaction of elemental sulfur with 2-R1 and 2,8-R1,R2-substituted tetracenes (2) in refluxing DMF affords 5,6,11,12 tetrathiotetracenes (1) in good yields (74-99%) for a range of substituents where R1,R2 are: H,H (a); Me,H (b); MeO,H (c); Ph,H (d); Me,Me (e), iPr,Me (f, iPr = iso-propyl, CHMe2), Me,M...
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| Language: | English |
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Royal Society of Chemistry
2018
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| Online Access: | https://eprints.nottingham.ac.uk/50403/ |
| _version_ | 1848798243125723136 |
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| author | Robert Garrett, Mary Durán-Peña, María Jesús Lewis, Willliam Pudzs, Kaspars Uzulis, Janis Mihailovs, Igors Tyril, Björk Shine, Jonathan Smith, Emily F. Rutkis, Martins Woodward, Simon |
| author_facet | Robert Garrett, Mary Durán-Peña, María Jesús Lewis, Willliam Pudzs, Kaspars Uzulis, Janis Mihailovs, Igors Tyril, Björk Shine, Jonathan Smith, Emily F. Rutkis, Martins Woodward, Simon |
| author_sort | Robert Garrett, Mary |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | Reaction of elemental sulfur with 2-R1 and 2,8-R1,R2-substituted tetracenes (2) in refluxing DMF affords 5,6,11,12 tetrathiotetracenes (1) in good yields (74-99%) for a range of substituents where R1,R2 are: H,H (a); Me,H (b); MeO,H (c); Ph,H (d); Me,Me (e), iPr,Me (f, iPr = iso-propyl, CHMe2), Me,MeO (g); MeO,MeO (h). The reaction rate is limited only by the solubility of the tetracene (2); 2g-h being both the least soluble and slowest reacting. At partial conversion recovered single crystalline 2g led to its X-ray structure determination. Vacuum deposited (substrate deposition temperature 300 K, pressure 7 × 10-6 mbar, source temperature 500 K) thin films from 1 (of initial 88-99% purity) show final electrical conductivities, σ(in plane) from 1.40 × 10-5 S cm-1 (1g) to 3.74 × 10-4 S cm-1 (1b) for the resultant near pristine films; while 1d proved too involatile to be effectively sublimed under these conditions. In comparison, initially 95% pure TTT (1a) based films show σ(in plane) = 4.33 × 10-5 S cm-1. The purities of 1a-h are highly upgraded during sublimation. Well defined micro-crystallites showing blade, needle or mossy like habits are observed in the films. The Seebeck coefficients (Sb) of the prepared 1 range from 374 (1c) to 900 (1f) μV K-1 (vs. 855 μV K-1 for identically prepared 95% pure TTT, 1a). Doping of films of 1f (R1 = iPr, R2 = Me) with iodine produces optimal p-type behaviour: σ(in-plane) = 7.00 × 10-2 S cm-1, Sb = 175 μV K-1. The latter’s Power Factor (PF) at 0.33 μW m-1 K-2 is more than 500-times that of the equivalent I2-doped TTT films (1a, R1 = R2 = H), previously regarded as the optimal material for thin film thermoelectric devices using acene radical cation motifs. |
| first_indexed | 2025-11-14T20:16:40Z |
| format | Article |
| id | nottingham-50403 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T20:16:40Z |
| publishDate | 2018 |
| publisher | Royal Society of Chemistry |
| recordtype | eprints |
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| spelling | nottingham-504032019-03-07T04:30:18Z https://eprints.nottingham.ac.uk/50403/ Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes Robert Garrett, Mary Durán-Peña, María Jesús Lewis, Willliam Pudzs, Kaspars Uzulis, Janis Mihailovs, Igors Tyril, Björk Shine, Jonathan Smith, Emily F. Rutkis, Martins Woodward, Simon Reaction of elemental sulfur with 2-R1 and 2,8-R1,R2-substituted tetracenes (2) in refluxing DMF affords 5,6,11,12 tetrathiotetracenes (1) in good yields (74-99%) for a range of substituents where R1,R2 are: H,H (a); Me,H (b); MeO,H (c); Ph,H (d); Me,Me (e), iPr,Me (f, iPr = iso-propyl, CHMe2), Me,MeO (g); MeO,MeO (h). The reaction rate is limited only by the solubility of the tetracene (2); 2g-h being both the least soluble and slowest reacting. At partial conversion recovered single crystalline 2g led to its X-ray structure determination. Vacuum deposited (substrate deposition temperature 300 K, pressure 7 × 10-6 mbar, source temperature 500 K) thin films from 1 (of initial 88-99% purity) show final electrical conductivities, σ(in plane) from 1.40 × 10-5 S cm-1 (1g) to 3.74 × 10-4 S cm-1 (1b) for the resultant near pristine films; while 1d proved too involatile to be effectively sublimed under these conditions. In comparison, initially 95% pure TTT (1a) based films show σ(in plane) = 4.33 × 10-5 S cm-1. The purities of 1a-h are highly upgraded during sublimation. Well defined micro-crystallites showing blade, needle or mossy like habits are observed in the films. The Seebeck coefficients (Sb) of the prepared 1 range from 374 (1c) to 900 (1f) μV K-1 (vs. 855 μV K-1 for identically prepared 95% pure TTT, 1a). Doping of films of 1f (R1 = iPr, R2 = Me) with iodine produces optimal p-type behaviour: σ(in-plane) = 7.00 × 10-2 S cm-1, Sb = 175 μV K-1. The latter’s Power Factor (PF) at 0.33 μW m-1 K-2 is more than 500-times that of the equivalent I2-doped TTT films (1a, R1 = R2 = H), previously regarded as the optimal material for thin film thermoelectric devices using acene radical cation motifs. Royal Society of Chemistry 2018-03-07 Article PeerReviewed application/pdf en https://eprints.nottingham.ac.uk/50403/1/Simon%20Woodward%20Synthesis%20and%20Thermoelectric.pdf Robert Garrett, Mary, Durán-Peña, María Jesús, Lewis, Willliam, Pudzs, Kaspars, Uzulis, Janis, Mihailovs, Igors, Tyril, Björk, Shine, Jonathan, Smith, Emily F., Rutkis, Martins and Woodward, Simon (2018) Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes. Journal of Materials Chemistry C . ISSN 2050-7496 http://pubs.rsc.org/en/Content/ArticleLanding/2018/TC/C8TC00073E#!divAbstract doi:10.1039/C8TC00073E doi:10.1039/C8TC00073E |
| spellingShingle | Robert Garrett, Mary Durán-Peña, María Jesús Lewis, Willliam Pudzs, Kaspars Uzulis, Janis Mihailovs, Igors Tyril, Björk Shine, Jonathan Smith, Emily F. Rutkis, Martins Woodward, Simon Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes |
| title | Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes |
| title_full | Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes |
| title_fullStr | Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes |
| title_full_unstemmed | Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes |
| title_short | Synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes |
| title_sort | synthesis and thermoelectric properties of 2- and 2,8-substituted tetrathiotetracenes |
| url | https://eprints.nottingham.ac.uk/50403/ https://eprints.nottingham.ac.uk/50403/ https://eprints.nottingham.ac.uk/50403/ |