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Because of the necessity of carry out electrolysis reactions with considerable quantity of organic molecules, the balance between solubility of starting material, solution conductivity and electrochemical stability of medium and intermediates are key factors in organic electrosynthesis. HFIP has several properties that favor its use in this research area as solvent, among them, its high hydrogen-bond donor has opened the possibility of fine tuning reactivity, mainly in anodic reactions because of the helpful effect on the stability of positive intermediates. The cost of this solvent has limited its broad application in chemistry, including electrosynthesis, but the possibility of using mixtures with other cosolvents has demonstrated to help to expand its use without losing the beneficial effect on the intermediates. In recent years several HFIP mixtures (HFIP/MeOH, HFIP/CH2Cl2, HFIP/H2O, HFIP/ACN, HFIP/MeNO2) have permitted the control the chemical microstructure of the electrolysis media and have let to adjust the solvent properties to fulfill the necessity of electrosynthesis. In this review will be discussed the general properties of HFIP and the mixtures reported to carry out electrochemical synthetic transformations of organic molecules, as well as the reactions where has been demonstrated the beneficial effect of HFIP solvent mixtures in the control of the electrogenerated intermediates. This approach has succeeded in organic electrosynthesis.

Various organic compounds were investigated as co-solvents in an ionic liquid (IL), N,N-butylmethyl pyrrolidinium bis(trifluoromethylsulfonyl)imide (Pyr14TFSI), based electrolyte for Li-S batteries. For the Pyr14TFSI/Co-solvent binary system, only 1,3-dioxolane (DOL) afforded stable cycling performance with reasonable Coulombic efficiency (CE). Further increase in DOL concentration leads to a higher initial capacity but deteriorated CE. In an attempt to balance CE and capacity, 2.0 M LiTFSI Pyr14TFSI/DOL (2:1) exhibited optimal performance in terms of initial discharge capacity of 896 mAhg−1 and CE of 98.1% for over 200 cycle. The role of DOL and salt concentration interplay in the binary electrolyte was simulated by ab-initio molecular dynamics (AIMD). The solvation energy with varying co-solvent and LiTFSI salt concentration provides useful information when looking toward implementing other IL-based electrolyte systems for Li-S chemistry.

We have investigated the inkjet-printing of TiO 2 films for the fabrication of dye-sensitized solar cells (DSSCs). In order to realize the uniform printing of TiO 2 films, the co-solvent ink was designed by introducing a drying agent to the ink. This co-solvent ink induces a circulating flow within ink droplets and leads to the uniform lines and films by inkjet. A theoretical model was used to predict the optimal ink-droplet pitches for the inkjet-printing of uniform lines. This model also contributes to the formation of uniform films since they are filled with the inkjet-printed lines. The inkjet-printed TiO 2 films were used as photoelectrodes for dye-sensitized solar cells. The thickness of the inkjet-printed Ti0 2 films was varied to optimize the photovoltaic performance of DSSCs. Since no organic additives were introduced into the TiO 2 inks, the feasibility of reducing the annealing temperature for TiO 2 photoelectrodes was investigated. This study may suggest an opportunity to fabricate DSSCs at low temperature.