## 3 Results
### Hexacyanorrate Anions  
In earlier work by [PERSON], [PERSON] and [PERSON] [50] for the hexacyanoferrate(II) anion intercalated in LDH, the N 1s peak was found at 397.1 eV for Fe(CN)\({}_{6}\)\({}^{4-}\) while for Fe(CN)\({}_{6}\)\({}^{3-}\) it was observed at 397.4 eV (Figure 9 left). The NIST database shows that Fe(CN)\({}_{6}\)\({}^{4}\) compounds have N 1s BE values of around 397.4 to 398.0 eV, while K\({}_{3}\)Fe(CN)\({}_{6}\) had a BE of 398.1 eV [51], indicating that there is a minor difference in BE for N 1s in these two anions. There were significant differences in the Fe 2p3/2 high-resolution spectra, with the Fe(CN)\({}_{6}\)\({}^{3-}\) exhibiting the main peak at a BE of 707.7 eV and a second peak at a BE of 709.5 eV. In contrast, the Fe(CN)\({}_{6}\)\({}^{4}\) spectrum exhibited only one peak at 707.8 eV (see Figure 14 in [50]). For K\({}_{4}\)Fe(CN)\({}_{6}\), the NIST database shows a BE value of 707.1 and 708.5 eV, while for K\({}_{3}\)Fe(CN)\({}_{6}\), it was reported at 709.6 eV [51]. [PERSON] et al. [89] used Fe-XANES analysis to show that partial reduction of the Fe(III) in the Fe(CN)\({}_{6}\)\({}^{4}\) intercalated LDH had taken place. Moreover, [PERSON], [PERSON] and [PERSON] [32] showed the reduction of Fe(III) in Fe(CN)\({}_{6}\)\({}^{4}\) complexes by Mossbauer spectroscopy. [PERSON] and [PERSON] [90] found that the Fe 2p3/2 for Fe(II) has a BE of about 1 eV lower than Fe(III) in their oxides. The same is true for the potassium hexacyanoferrates and in this study of intercalated LDH with hexacyanoferrates. [PERSON], [PERSON] and [PERSON] [50] concluded that the Fe 2p3/2 peak at 707.7 eV is due to Fe(II) caused by partial reduction in the initial Fe(III) observed at 709.46 eV. In their study, they did not report on the C 1s results for these two samples; for the Fe(CN)\({}_{6}\)\({}^{4-}\) LDH, the C 1s of the C-N bond was observed at a BE value of 283.5 eV while for Fe(CN)\({}_{6}\)\({}^{3-}\) LDH at was observed at 283.9 eV (Figure 9 right). These BE values, and the small difference between the two compare well with the values and differences reported for K\({}_{4}\)Fe(CN)\({}_{6}\) at 283.5 eV and K\({}_{3}\)Fe(CN)\({}_{6}\) at 283.9 eV [51]. The infrared and Raman spectra of hexacyanoferrate intercalated LDH have been reported for the last 30 years. [PERSON] and [PERSON] [91] reported a band around 2000 cm\({}^{-1}\) was assigned to the CN stretching mode. In contrast, [PERSON], [PERSON] and [PERSON] [32] observed for the anion-exchanged LDH in an aqueous solution of K\({}_{3}\)Fe(CN)\({}_{6}\) resulted in two bands at 2120 and 2040 cm\({}^{-1}\) in the CN stretching region, indicating that part of the cyanoferrate(III) complex was reduced to cyanoferrate(II) complex during the intercalation. They based this on the fact that pure K\({}_{3}\)Fe(III)(CN)\({}_{6}\) and K\({}_{4}\)Fe(II)(CN)\({}_{6}\).3H\({}_{2}\)O produce IR active bands at 2120 and 2040 cm\({}^{-1}\), respectively. After the intercalation of Fe(CN)\({}_{6}\)\({}^{4-}\) in the LDH, no change in the oxidation state of Fe was detected. A band at 2040 \(\pm\) 4 cm\({}^{-1}\) was the stretching vibration of \(\
u\)(CN) of Fe(CN)\({}_{6}\)\({}^{4-}\) intercalated in LDH by [PERSON] et al. [92]. [PERSON], [PERSON] and [PERSON] [29] reported two bands at 2038 and 2113 cm\({}^{-1}\) for Fe(CN)\({}_{6}\)\({}^{3-}\) intercalated Ni/Al-LDH assigned to CN bound to Fe(II) and to CN bound to Fe(III), respectively. [PERSON] et al. [93] described an intense sharp band at 2094 cm\({}^{-1}\) attributed to the CN stretching mode of hexacyanoferrate(III) anions, but in addition, two weak bands were observed around 2002 and 2163 cm\({}^{-1}\). The band at 2002 cm\({}^{-1}\) was interpreted as being due to the partial reduction of Fe\({}^{3+}\) to Fe\({}^{2+}\). The weak band at 2163 cm\({}^{-1}\) was thought to be the result of the formation of nickel ferricanide, in which the hexacyanoferrate(III) anion is free from the LDH layers. Likewise, [PERSON] et al.