LiTFSI
Lithium bis(trifluoromethylsulphonyl)imide (LiTFSI) is normally used as a p-dopant to enhance the conductivity and hole mobility of the Spiro-OMeTAD for perovskite solar cells. It is believed that The function of LiTFSI in PSCs is similar to that in solid-state dye-sensitised solar cells [2].
Some of the lithium ions can intercalate into TiO2 to downshift its conduction band, resulting in a higher photocurrent. The rest of the lithium ions can react with oxygen and Spiro-OMeTAD to facilitate the generation of oxidised Spiro-OMeTAD, while the large anionTFSI¯, can stabilise the oxidized Spiro-OMeTAD as the counterion [1, 2].
It is also essential to add Lithium bis(trifluoromethanesulfonyl)imide to the hole transport materials (HTM) to get a higher conductivity.
General Information
| CAS number | 90076-65-6 |
| Chemical formula | C2F6LiNO4S2 |
| Molecular weight | 287.09 g/mol |
| Synonyms |
Lithium bis(trifluoromethanesulfonyl)imide, Bis(trifluoromethane)sulfonimide lithium salt |
| Classification / Family | Dye Sensitised Solar Cells (DSSC) , Light-emitting Diodes, Perovskite HTL Materials, Electrolyte materials. |
| Storage | Product is hygroscopic. Store under inert atmosphere or in a dessicator. |
Product Details
| Purity | 99.99% |
| Boiling point | 234-238 °C (lit.) |
| Colour | White powder/crystals |
Chemical Structure
| Device structure | FTO/c-TiO2/mp-Al2O3/CH3NH3PbBr3−xClx/CBP/Au [3] | FTO/c-TiO2/mp-Al2O3/CH3NH3PbBr3−xClx/ CBP:(TBP:LiTFSI, 10% wt)/Au |
| Jsc (mA cm-2) | 1.3 | 4.0 |
| Voc (V) | 1.4 | 1.5 |
| FF (%) | 24 | 46 |
| PCE (best) | 0.44 | 2.7 |
Characterisation (NMR)
Literature and Reviews
- Spectrum-Dependent Spiro-OMeTAD Oxidization Mechanism in Perovskite Solar Cells, S Wang et al., ACS Appl. Mater. Interfaces 7, 24791-24798 (2015). DOI: 10.1021/acsami.5b07703.
- Lithium salts as “redox active” p-type dopants for organic semiconductors and their impact in solid-state dye-sensitized solar cells, A. Abate et al., Phys. Chem. Chem. Phys., 15, 2572-2579 (2013). DOI: 10.1039/C2CP44397J.
- Chloride Inclusion and Hole Transport Material Doping to Improve Methyl Ammonium Lead Bromide Perovskite-Based High Open-Circuit Voltage Solar Cells, E. Edri et al., J. Phys. Chem. Lett., 5 (3), 429–433 (2014), DOI: 10.1021/jz402706q.
- Sequential deposition as a route to high-performance perovskite-sensitized solar cells, J. Burschka et al., Nature, 499, 316-319 (2013). doi:10.1038/nature12340.
To the best of our knowledge the technical information provided here is accurate. However, Ossila assume no liability for the accuracy of this information. The values provided here are typical at the time of manufacture and may vary over time and from batch to batch.