The ability to efficiently harvest heat as a source of sustainable energy would make a significant contribution to reducing our current reliance on fossil fuels. Waste heat sources, such as those produced in industrial processes or through geothermal activity, are extensive, often continuous, and at present severely underutilised. Thermoelectrochemical cells offer an alternative design to the traditional semiconductor-based thermoelectric devices and offer thepromise of continuous and cheap operation at moderate temperatures, low maintenance and with no carbon emissions. They utilise two electrodes, held at different temperatures, separated by an electrolyte containing a redox couple. It is the temperature dependence of the electrochemical redox potential that generates the potential difference across the device as a result of the appliedtemperature difference. The magnitude of this redox potential temperature dependence is given by the Seebeck coefficient, Se. Until recently, research into thermoelectrochemical cells had primarily focused on aqueous media, predominantly with the Fe(CN)63-/4- redox couple.[1] However, the good thermal and electrochemical stability, non-volatility and non-flammability ofmany ionic liquids make them promising alternative electrolytes for these devices. The use of ionic liquid (IL) electrolytes offers potential advantages that include increased thermoelectrochemical device efficiencies and lifetimes and the ability to utilise low temperature (often “waste”) heat sources in the 100 – 200 °C temperature range.[2] Here we discuss our research into the use of the Fe(CN)63-/4- redox couple in protic IL electrolytes, with different amounts of added water, in a thermoelectrochemical device with platinum and single walled carbon nanotube (SWNT) electrodes.

This manuscript reports investigation conducted on room temperature ionic liquids (RTILs) C1CnImNTf2/n=4, 6 in order to use it as electrolyte solvent in lithium ion battery. The ionic conductivity, viscosity, ion self-diffusion coefficients, and electrochemical stability in C1CnImNTf2 are presented. A solution of C1CnImNTf2/n=4, 6 containing 1.6 mol.L-1 of LiNTf2 has been used as the electrolyte in a Li-ion battery with graphite and LiFePO4 as respectively negative and positive active materials. [Li][C1C6Im][NTf2] shows the best cycling performance: a capacity up to 120 mAh.g-1 at C/10 rate at 25°C.

Surface smoothing of a barium borosilicate glass substrate by irradiation of ionic liquid ion beams were investigated. 1-ethyl-3-methylimidaolium tetrafluoroborate (EMIM-BF4) and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6) were used for the source liquid. Surface roughness represented as the arithmetic mean value decreased from 0.17 nm to 0.13 nm by the BMIM-PF6 negative ion beam. Secondary electron microscope (SEM) observation for the glass surface irradiated with the BMIM-PF6 negative ion beam showed a clear image without an electrical charge-up, though the EMIM-BF4 negative ion beam irradiated glass yielded a charged up image. X-ray photoelectron spectroscopy (XPS) analysis implied that the surface layer including cation-anion pair of BMIM-PF6 was deposited by the BMIM-PF6 negative ion beam irradiation, while an insulated surface with barium fluoride was formed by the EMIM-BF4 negative ion beam irradiation.

Ionic liquid (IL) is used as the working electrolyte in ionic polymer metal composite (IPMC) electromechanical bending actuators because of its high stability and conductivity, which are crucial for the consistency and speed of the actuation. Because the bending actuation is caused by the migration and accumulation of the cations and anions of the IL, it is clear that both the overall number of ions and the effectiveness of ion transport and accumulation play important roles in the actuation behavior. In this paper, the effect of enhancing the ion accumulation by the self-assembled conductive network composite (CNC) layers is investigated by comparing the bending behavior of actuators with and without CNC layers. In addition, IPMC actuators with various IL uptakes are also tested in order to study the dependence of the bending performance on the amount of the ions available. It is found that, with the CNC layers, the maximum bending curvature of the actuator increases with increased IL, which shows the crucial role played by the IL. However, under the same conditions, the performance improvement of actuators without CNC layers saturates when the IL uptake reaches around 10% wt. This demonstrates the role of the CNC layers to provide a porous electrode with increased capacitance that thus accommodates accumulation of more ions near the electrodes, which in turn boosts the overall bending curvature of the actuator.

Ionic liquid (IL) ion sources with different emitter tip materials and tip numbers were developed and examined on ion beam characteristics with respect to its ILs wettability. As a result of ion current measurements, the most stable emission current was obtained for the graphite emitter tip and the ion current increased with increase of the tip number. The results indicate that the emitter wettability corresponding to the supplying flow rate and the number of emission site play an important role to stabilize and increase the beam current.