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LiMnPO 4 nanoparticles synthesized by the polyol method were examined as a cathode material for advanced Li-ion batteries. The structure, surface morphology, and performance were characterized by X-ray diffraction, high resolution scanning electron microscopy, high resolution transmission electron microscopy, Raman, Fourier transform IR, and photoelectron spectroscopies, and standard electrochemical techniques. A stable reversible capacity up to 145 mAh g −1 could be measured at discharge potentials Ͼ4 V vs Li/Li + , with a reasonable capacity retention during prolonged charge/discharge cycling. The rate capability of the LiMnPO 4 electrodes studied herein was higher than that of LiNi 0.5 Mn 0.5 O 2 and LiNi 0.8 Co 0.15 Al 0.05 O 2 ͑NCA͒ in similar experiments and measurements. The active mass studied herein seems to be the least surface reactive in alkyl carbonate/LiPF 6 solutions. We attribute the low surface activity of this material, compared to the lithiated transition-metal oxides that are examined and used as cathode materials for Li-ion batteries, to the relatively low basicity and nucleophilicity of the oxygen atoms in the olivine compounds. The thermal stability of the LiMnPO 4 material in solutions ͑measured by differential scanning calorimetry͒ is much higher compared to that of transition-metal oxide cathodes. This is demonstrated herein by a comparison with NCA electrodes. 2 Among them, LiMnPO 4 is of particular interest as it offers the advantages of a flat discharge voltage profile at 4.1 V vs Li/Li + , the expected safety features, and an abundance of the relevant elements in the earth's crust.1-6 Hence, LiMnPO 4 can be an ideal substitute for the commonly used cathode material, LiCoO 2 , which is expensive, toxic, and demonstrates problematic safety features. The three-dimensional framework of the olivine structure is stabilized by the strong covalent bonds between the oxygen and the P 5+ ions, resulting in PO 4 3− tetrahedral polyanions. As a result, lithium metal phosphate materials do not undergo a structural rearrangement during lithiation and delithiation. This indicates that LiMPO 4 electrodes may demonstrate better stability and capacity retention during prolonged cycling as compared to lithiated transition-metal oxide cathode materials such as LiCoO 2 , LiNiO 2 , LiMnO 2 , and LiMn 2 O 4 . However, LiMPO 4 compounds and LiMnPO 4 , in particular, suffer from poor electronic and ionic ͑Li + ͒ conductivity, which means a limited rate capability ͑especially at low temperatures͒.

Raman spectroscopy has been used to obtain Raman spectra of yttria‐stabilized tetragonal zirconia subject to surface nitridation induced by contact with zirconium nitride. Raman spectra recorded from regions at increasing distance from the source of nitridation have been used to obtain diffusion profiles from samples treated at different times and temperatures. The coupling of X‐ray diffraction data previously taken and of the Raman spectra shows that in the samples there is a two‐phase region (tetragonal + cubic) near the nitrided surface and that, at larger distance inside the samples, there is only one phase (tetragonal). Fitting of the diffusive profiles in the single‐phase tetragonal region with an appropriate diffusion function allows the determination of the diffusion coefficient of nitrogen in tetragonal zirconia which is expressed in terms of the preexponential factor, D0= (3.98 ± 0.5) × 10−3 cm2/s, and the activation energy, Q= 170 ± 10 kJ/mol.