We report Arbuzov-type reactions of chlorofullerene C₆₀Cl₆ with trialkyl phosphites producing highly functionalized fullerene derivatives C₆₀[P(O)(OR)₂]₅H with high yields. The designed family of [60]fullerene phosphonic acids and their esters showed unusual properties which might find valuable material science applications.

This review is devoted to different types of novel polymer electrolytes for lithium power sources developed during the last decade. In the first part, the compositions and conductivity of various polymer electrolytes are considered. The second part contains NMR applications to the ion transport mechanism. Polymer electrolytes prevail over liquid electrolytes because of their exploitation safety and wider working temperature ranges. The gel electrolytes are mainly attractive. The systems based on polyethylene oxide, poly(vinylidene fluoride-co-hexafluoropropylene), poly(ethylene glycol) diacrylate, etc., modified by nanoparticle (TiO₂, SiO₂, etc.) additives and ionic liquids are considered in detail. NMR techniques such as high-resolution NMR, solid-state NMR, magic angle spinning (MAS) NMR, NMR relaxation, and pulsed-field gradient NMR applications are discussed. ¹H, ⁷Li, and ¹⁹F NMR methods applied to polymer electrolytes are considered. Primary attention is given to the revelation of the ion transport mechanism. A nanochannel structure, compositions of ion complexes, and mobilities of cations and anions studied by NMR, quantum-chemical, and ionic conductivity methods are discussed.

The main particularities of sulfonate groups hydration, water molecule and alkaline metal cation translation mobility as well as ionic conductivity were revealed by NMR and impedance spectroscopy techniques. Cation-exchange membranes MSC based on cross-linked sulfonated polystyrene (PS) grafted on polyethylene with ion-exchange capacity of 2.5 mg-eq/g were investigated. Alkaline metal cation hydration numbers (h) calculated from temperature dependences of ¹H chemical shift of water molecule for membranes equilibrated with water vapor at RH = 95% are 5, 6, and 4 for Li⁺, Na⁺, and Cs⁺ ions, respectively. These values are close to h for equimolar aqueous salt solutions. Water molecules and counter ions Li⁺, Na⁺, and Cs⁺ diffusion coefficients were measured by pulsed field gradient NMR on the ¹H, ⁷Li, ²³Na, and ¹³³Cs nuclei. For membranes as well as for aqueous chloride solutions, cation diffusion coefficients increased in the following sequence: Li⁺ < Na⁺ < Cs⁺. Cation and water molecule diffusion activation energies in temperature range from 20 °C to 80 °C were close to each other (about 20 kJ/mol). The cation conductivity of MSC membranes is in the same sequence, Li⁺ < Na⁺ < Cs⁺ << H⁺. The conductivity values calculated from the NMR diffusion coefficients with the use of the Nernst–Einstein equation are essentially higher than experimentally determined coefficients. The reason for this discrepancy is the heterogeneity of membrane pore and channel system. Ionic conductivity is limited by cation transfer in narrow channels, whereas the diffusion coefficient characterizes ion mobility in wide pores first of all.

We report the synthesis and comparative study of five conjugated polymers P1–P5 with different arrangements of two solubilizing 2-ethylhexyl side chains in their repeating units. It has been shown that positioning of the alkyl substituents affects strongly frontier energy levels of the polymers and results in variation of their optical band gaps between 1.65 and 2.0 eV. The highest (2.8 × 10⁻⁴ cm² V⁻¹ s⁻¹) and the lowest (2.4 × 10⁻⁵ cm² V⁻¹ s⁻¹) charge carrier mobilities determined for the polymers P1 and P5, respectively, using a SCLC technique differ by more than one order of magnitude. GIWAXS measurements also revealed very different degrees of molecular ordering in the films of polymers P1–P5 which correlate well with the SCLC mobility data and solid state photoluminescence spectra of these materials. The bulk heterojunction solar cells based on the composites of polymers P1–P5 with [60]PCBM demonstrated power conversion efficiencies ranging from 0.6% (P5) to 5.1% (P1) thus evidencing a strong influence of the alkyl side chains on the photovoltaic performance of the designed polymer-based materials.