## 3 Results
### Characterization
The band at 1635 cm\({}^{-1}\) can be associated with physisorbed water (from exposure prior to analysis), and a broad peak between 3200 cm\({}^{-1}\) and 3600 cm\({}^{-1}\) indicates OH stretching exhibited by hydroxyl functional groups [39, 40]. The FTIR spectra of the RAWOS and RAWS catalysts displayed similar peaks to those observed in spectra for ALVIR. Ru-O vibrations are expected to occur between 600 and 800 cm\({}^{-1}\) and thus a distinction between Al-O and Ru-O bands could not be clearly made. Bands originating from the functional groups associated with PEG (the main C-O-C band at 1094 cm\({}^{-1}\)) in the RAWS sample were not observed, which implies that the PEG was removed by the heat treatment. The RAWOS and RAWS supported catalysts were additionally characterized using XPS (Figure 4). The spectra were de-convoluted by using a Gauss-Laurentzian peak fitting program. The respective high resolution core level Al 2p, Ru 3d and Ru 3p spectra are given for the catalyst RAWOS (Figure 4a-c) and RAWS (Figure 4d-f). The binding energy values observed in the Al 2p spectra of both catalysts correspond to Al\({}_{2}\)O\({}_{3}\) as expected [41]. Spectra also contained peaks corresponding to carbon (284.5 eV) and Ru 3d peaks typical for ruthenium oxides (286.2 and 286.0 eV) [42]. Since the Ru 3d and C 1s peaks are very close in terms of binding energy values, spectra in the Ru 3p binding energy are expected to be more stable than those observed in the literature. Figure 3: Formation mechanism of 1-D RuOx in the presence of PEG. energy region were recorded to clarify the ruthenium oxidation state and bonding environment. From the positions and relative intensity of the observed peaks, the RAWOS sample surface consisted of approximately 68 at.% Ru (IV) (typical of RuO\({}_{2}\); 462.4 eV) and approximately 32 at.% RuO\({}_{3}\) (465.0 eV) [42, 43]. By comparison, Ru 3p peaks for the RAWS sample surface reflected an approximate composition of 62 at.% RuOx (_i.e._, higher oxides of Ru, where \(x=3\) mostly) at 464.3 eV and 38 at.% elemental Ru\({}^{\circ}\), (461.8 eV) [42]. It has been reported that RuO\({}_{3}\) is found in all of the surfaces of RuO\({}_{2}\) and it plays a main role in the stability of RuO\({}_{2}\)[42]. It is clearly seen that when the sample was prepared with a polymer stabilizer such as PEG (as is the case for the RAWS), formation of metallic Ru is induced through the reducing activity of the stabilizer [44]. The adsorption capacity of gas molecules within the pores of the catalyst is an important step towards understanding the catalyst reaction. This can be determined from the surface and pore-characteristics of the catalyst. Figure 5 shows the N\({}_{2}\) adsorption-desorption isotherm (Figure 5a-c) and the multipoint Brunauer-Emmet-Teller (BET) plots (Figure 5d-f) for the ALVIR, RAWOS and RAWS materials, respectively. From the sorption profiles it is evident that the catalysts exhibit mesoporous type IV isotherm behavior in which the intake of adsorbate increases at high pressure. The pore volume and pore radius of the catalysts during adsorption and desorption process calculated by Barrett-Joyner-Halenda (BJH) method are listed in Table 1, which confirmed the standard values of the pore size (1.5-100 nm) reported [45]. The linearity of the data (indicating a strong interaction of the ruthenium oxide catalyst with N\({}_{2}\)) in the relative pressure (P/P\({}_{0}\)) range of 0.0-0.3 reinforces the suitability of applying the BET model in determining the specific surface area of the catalysts. Figure 4: High resolution core level Al 2p, Ru 3d and Ru 3p spectra corresponding to RAWOS (**a–c**) and RAWS (**d–f**) catalysts. The BET surface area is generally used for practical purposes. The ALVIR, RAWOS and RAWS catalysts exhibit BET surface area values of _ca._ 112.2, 138.3 and 128.1 m\({}^{2}\cdot\)g\({}^{-1}\), respectively.