Synthesis and characterisation of protic ionic liquids for electrochemical applications
The suitability of a series of protic ionic liquids to be used in electrochemical devices was assessed. Out of fourteen synthesised compounds, four were chosen for further characterisation. Their identity was con rmed by NMR spectroscopy, followed by an investigation into their viscometric properties. It was discovered that they obey a simple Arrhenius relationship at low temperatures, and the Arrhenius parameters eta and Ea were determined. After a series of cyclic voltammetry and thermogravimetric decomposition measurements, it was determined that these PIL's were likely to be stable for at least a 1.5V window and from 25oC to at least 1500C. Their water content was discovered to be high, ranging from 2.75 - 23.8ppm: on this basis it was determined that they are hygroscopic at ambient conditions. Lastly, their glass transition, melting and crystallisation temperatures, along with their latent heats of fusion and crystallisation, were measured by DSC. The PIL's were incorporated into a PVDF-co-HFP polymer matrix, but the synthesis was largely unsuccessful as they degraded readily at low temperatures.