One main limiting factor for the technoeconomics of future bioprocesses that use ionic liquids (ILs) is the recovery of the expensive and potentially toxic IL. We have demonstrated a new series of phase-separable ionic liquids, based on the hydrophobic tetraalkylphosphonium cation ([PRRRR](+)), that can dissolve lignin in the neat state but also hemicellulose and high-purity cellulose in the form of their electrolyte solutions with dipolar aprotic solvents. For example, the IL trioctylmethylphosphonium acetate ([P8881][OAc]) was demonstrated to dissolve up to 19 wt % of microcrystalline cellulose (MCC) at 60 °C with the addition of 40 wt % of DMSO. It was found that the MCC saturation point is dependent on the molar ratio of DMSO and IL in solution. At the optimum saturation, a ∼1:1 molar ratio of [P8881][OAc] to anhydroglucose units is observed, which demonstrates highly efficient solvation. This is attributed to the positive contribution that these more amphiphilic cation-anion pairs provide, in the context of the Lindman hypothesis. This effective dissolution is further illustrated by solution-state HSQC NMR spectroscopy on MCC. Finally, it is also demonstrated that these electrolytes are phase separable by the addition of aqueous solutions. The addition of 10 % NaOAc solution allows a near quantitative recovery of high-purity [P8881][OAc]. However, increased volumes of aqueous solution reduced the recovery. The regenerated material was found to partially convert into the cellulose II crystalline polymorph.

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This paper reviews several high‐k ALD processes potentially applicable to the production of capacitors, concentrating on very recent developments. A list of the dielectric materials under investigation consists of the oxides of several metals, including the Group 4 (Ti, Zr, Hf) elements. The binary oxides of Group 4 metals, as well as their mixtures with other oxides, doped hosts, or multi‐layers in the form of nano‐laminates are of interest.Several examples of our recent results are shown, including possible ALD routes to materials not previously grown, as well as advances in process development.

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Lithium phosphate, Li 3 PO 4 , has been considered a potential electrolyte material for lithium ion batteries and CO 2 sensors in particular if the films can be made dense and of high quality already at low thickness. In this work, Li 3 PO 4 thin films were deposited by atomic layer deposition (ALD) between 225 and 350 • C using trimethyl phosphate and either of the two lithium sources, namely lithium hexamethyldisilazide or lithium tert-butoxide. The deposited films showed slightly crystalline Li 3 PO 4 structure in X-ray diffraction and the elastic recoil detection analysis confirmed this stoichiometry with some carbon and hydrogen impurities. The crystallinity and thermal stability of the films at elevated temperatures in N 2 were also examined. The long term stability of the deposited Li 3 PO 4 films under ambient air may be an issue for the applicability of these processes. Lithium phosphate, Li 3 PO 4 , can be applied as an electrolyte in solid state lithium ion batteries 1-3 and CO 2 gas sensors. 4-6 Also optical humidity sensors based on Li 3 PO 4 have been presented recently. 7 Thin Li 3 PO 4 film has also been used as an interfacial layer between LiCoO 2 electrode and solid polymer electrolyte in solid state lithium ion battery. 8 Crystallization of Li 3 PO 4 greatly decreases the ionic conductivity: amorphous Li 2.7 PO 3.9 has an ionic conductivity of 6.6 × 10 −8 S/cm while the polycrystalline γ-Li 3 PO 4 has been extrapolated to be highly resistive with as low conductivity as 4.2 × 10 −18 S/cm at 25 • C. 9 Even if the ionic conductivity is only moderate, amorphous Li 3 PO 4 is still a potential electrolyte material provided it can be made dense already at low thickness.In lithium ion battery applications the 3D structuring of the materials would be a way to effectively increase the energy storage capacity by increasing the specific surface area. 10, 11 Atomic layer deposition (ALD) 12-15 may prove to be useful for depositing thin films on demanding 3D structures as films grown by ALD inherently possess good conformality and uniformity because of the alternating, saturative precursor doses and self-limiting surface reactions. The resulting accurate thickness controllability and repeatability of the films is a major benefit of the layer by layer approach used in ALD. Some of the electrolyte material candidates for 3D batteries include for example Li 3 PO 4 and nitrogen mixed lithium phosphate known as LiPON. 10,11 ALD processes for phosphate films are very few in number, although aluminum phosphate thin films have been deposited already in the 90's. 16,17 Besides aluminum phosphate, only ALD of calcium phosphate has been published. 18 Also lithium containing ALD processes were absent until recent reports on ALD of lithium hydroxide, lithium carbonate, lithium aluminate, lithium silicate, lithium lanthanate and lithium lanthanum titanates. [19][20][21][22][23] In addition, ALD of LiFePO 4 and Ca:LaPO 4 materials have been recently presented. 24,25 Here we report ALD growth and characterization of lithium...

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