The hybrid organic−inorganic material formed by polyaniline and the hexacyanoferrate anion (PAni/HCF) constitutes a molecular hybrid where the anchoring of the electroactive anion within the polymer leads to its application as a functional material that harnesses the activity of the molecular species. Transport measurements of the hybrid have been carried out, both by cyclic voltammetry at different scan rates and ac impedance spectroscopy. An apparent diffusion coefficient of 5 × 10-8 cm2/s and an activation energy of 15.5 kJ/mol (0.16 eV) have been obtained. The particular application of these hybrids to energy storage is shown here through their use as cathodes in lithium rechargeable cells. In this respect, the PAni/HCF hybrids show very good cyclabilities and high specific charges of up to 140 A·h/kg, unprecedented for this type of hybrid materials.

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A study of the hybrid organic-inorganic hexacyanoferrate-polypyrrole material as a cathode in rechargeable lithium cells is reported as part of a series of functional hybrid materials that represent a new concept in energy storage. The effect of synthesis temperatures of the hybrid in the specific capacity obtained from the cell is discussed. However specific capacities are obtained for materials synthesized at lower temperatures (0ЊC). The preparation method of the electrodes is also a parameter of great importance: thin film cathodes made with poly(vinylidene fluoride) as a binder and Super P carbon as conducting additive show higher specific capacities than powder cathodes. These materials present modest specific capacities of up to 69 Ah/kg but withstand repeated cycles of charge/discharge with no loss of capacity, even with an initial gain during the first 60 cycles.

This paper offers direct evidence for the electrochemical intercalation of oxygen in an oxide with the K2NiF4 structure, namely, La2CuO4, at room temperature. Organic solvents, as well as water, allow that reaction to occur. The charge-to-mass ratio evaluated from a comparison with fluoride intercalation implies that either OH- or Oδ- species are being intercalated. Comparison with previous work seems to favor the latter. If an oxygen with lower charge is moving, that could indeed explain why oxygen conductivity can be observed at such low temperatures.

Hybrid materials useful as electrodes in plastic batteries are investigated by these authors. The electroactive species hexacyanoferrate (HCF) and the conducting organic polymer polyaniline (PAni) are combined to create hybrid materials that show promise as cathode materials in rechargeable lithium batteries. The chemical and electrochemical synthesis of PAni/HCF as well as the material's electrochemical properties are reported. It is demonstrated that this material has not only a high specific charge and efficiency but also good cyclability.