General Information
CAS number 90076-65-6
Chemical formula C2 F6 LiNO4 S2
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
Chemical structure of Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) , CAS No. 90076-65-6
Applications
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.
Device structure
FTO/c-TiO2 /mp- Al2 O3/ CH3 NH3 PbBr3−x Clx /CBP/Au [3]
FTO/c-TiO2 /mp- Al2 O3 /CH3 NH3 PbBr3−x Clx / CBP:(TBP:LiTFSI , 10% wt)/Au
J sc (mA cm-2 )1.3
4.0
V oc (V)1.4
1.5
FF (%) 24
46
PCE (best) 0.44
2.7
Characterisation (NMR)
19 F NMR of
Lithium bis(trifluoromethanesulfonyl)imide ( LiTFSI) in
d6 -DMSO (
see full version )
Literature and Reviews
Spectrum-Dependent Spiro-OMeTAD Oxidization Mechanism in Perovskite Solar Cells,
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.
