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Disordered lithium-rich transition metal oxyfluorides with a general formula Li$_{1+x}$MO$_{2}$F$_{x}$ (M being a transition metal) are gaining more attention due to their high specific capacity which can be delivered from the facecentered cubic (fcc) structure. The most common synthesis procedure involves use of mechanosynthesis. In this work, ceramic synthesis of lithium rich iron oxyfluoride and lithium rich titanium oxyfluoride are reported. Two ceramic synthesis routes are developed each leading to the different level of doping with Li and F and different levels of cationic disorder in the structure. Three different Li$_{1+x}$MO$_{2}$F$_{x}$ samples (x ¼ 0.25, 0.3 and 1) are compared with a sample prepared by mechanochemical synthesis and non-doped LiFeO2 with fcc structure. The obtained lithium rich iron oxyfluoride are characterized by use of M€ossbauer spectroscopy, X-ray absorption spectroscopy, NMR and TEM. Successful incorporation of Li and F have been confirmed and specific capacity that can be obtained from the samples is in the correlation with the level of disorder introduced with doping, nevertheless oxidation state of iron in all samples is very similar. Conclusions obtained from lithium rich iron oxyfluoride are validated by lithium rich titanium oxyfluoride.

Titania nanoparticles were synthesized by employing the hydrothermal method and using TiOSO 4 as a titanium source. By varying pH between 0.5 and 1.0 and adding isopropanol to the hydrothermal reaction mixture, different mixtures ofanata- se, rutile, and brookite were obtained. The samples were also doped with nitrogen at different N concentrations using, res- pectively, urea, ammonium nitrate, and tripropylamine as nitrogen sources. The samples were characterized by X-ray pow- der diffraction, field emission scanning electron microscopy, infrared spectroscopy, UV-Vis diffuse reflectance spectros- copy and according to their specific surface area. Additionally, their photocatalytic activity was measured in a gas-solid reactor system. The results show that low pH favours rutile formation, whereas a higher pH yields mixed phase titania poly- morphs. Isopropanol addition also favours rutile formation, and boosted the photocatalytic activity of the resulted particles. Contrary to most data in the literature, rutile turned out to be the more active phase in the present investigation. Nitrogen doping, on the other hand,did not contribute to higher photocatalytic activity, but was rather detrimental to it. S hidrotermalno metodo smo sintetizirali nanodelce titanovega oksida. Kot izvor titana smo uporabili TiOSO4. Spreminjali smo pH med 0,5 in 1,0 ter dodatek izopropanola v reakcijsko zmes in s tem pripravili različne zmesi anataza, rutila in brookita. Vzorce smo tudi dopirali z različnimi deleži dušika, pri čemer smo kot izvor dušika uporabili sečnino, amonijev nitrat in tripropilamin. Vzorce smo karakterizirali z rentgensko praškovno difrakcijo, elektronsko vrstično mikroskopijo na poljsko emisijo, infrardečo spektroskopijo, UV-Vis difuzno refleksijsko spektroskopijo in jim določali specifično površino. Fotokatalitsko aktivnost pa smo merili v reaktoskem sistemu plin-trdno. Ugotovili smo, da nizek pH favorizira nastajanje rutila, medtem ko višje vrednosti pH vodijo do mešanih polimorfnih faz titanovega oksida. Tudi dodatek izopropanola pospešuje nastajanje rutila. V nasprotju z večino literaturnih podatkov je bila v naši raziskavi najbolj fotokatalitsko aktivna rutilna modifikacija. Dopiranje z dušikom pa ne poveča fotokatalitske aktivnosti, ampak jo celo nekoliko zmanjša.

Sample preparation is the most important part of a successful measurement withan atomic force microscope (AFM). While various kinds of substrates are used for that purpose, atomically flat gold proved to possess some advantages,namely chemical inertness against oxygen, stability against radicals and suitability for formation of self-assembled monolayers (SAMs) of organic alkanethiols. Fast and simple preparation procedures to achieve quality atomically flat gold substrates are necessary to achieve reproducible results in high resolution imaging. Here we report an improved technique to produce atomically flat gold in a reliable way. We demonstrate its use on the example of high resolution imaging of single walled carbon nanotubes as test molecules.