Comparison of the Sn L edge X-ray absorption spectra and the corresponding electronic structure in Sn, SnO, and SnO2

Structural and physical properties of transparent conducting, amorphous Zn-doped SnO2 films

“…This energy difference is comparable to that of the Sn L 1 absorption edges reported for SnO and SnO 2 . 39 This supports the conclusion that the brownish tint observed in this film is due to the formation of Sn 2þ (up to 30%, as estimated from the peak ratio). In bulk SnO, Sn is coordinated by 4 oxygen, 40 and is likely to be the same for the Sn 2þ ions in this a-ZTO film; the small coordination number around Sn obtained for the a-ZTO70 film (Table I), which was similarly brownish in color, substantiates this conclusion.…”

Redox profile of the glass surface

“…The maximum is seen to shift from 3954 eV for XAS spectra recorded at the sample surface to 3961 eV for spectra recorded at depth higher than 5-10 μm. Apart from a shift of 4 eV attributed to a different monochromator calibration, and a smoothing of the overall structures due to the glassy state of our samples, those spectra are in line with those recorded by Liu et al on reference compounds [14]. In particular the 7 eV blue shift of the main maximum is attributed to the switch from SnO to SnO 2 .…”

“…XANES of sulfur in several well characterized compounds were purposely recorded. Tin spectra were compared with published data [14]. Finally, the oxydation state of iron was determined by an analysis of the pre-peaks [12,15,16] as explained below.…”

Sulfur-Modulated Tin Sites Enable Highly Selective Electrochemical Reduction of CO2 to Formate

“…34,35 In situ Sn L 3 -edge spectra at À0.7 V versus RHE indicate that the reduction of SnS x to Sn(S) resulted in an oxidation state between Sn 0 and Sn 2+ , while Sn NPs do not change oxidation state ( Figure 4A). 36,37 This suggests Sn(S) at À0.7 V versus RHE was more oxidized than Sn metal, which agreed with the in situ S K-edge spectra 38 ( Figure S11). The trend observed from the Sn L 3 -edge ( Figure 4B) indicates that sulfur-doped Sn possessed a higher oxidation state than Sn NPs after reaction (edge shift indicated by a red arrow), 36,37 consistent with Sn K-edge measurements ( Figure 4C).…”

“…36,37 This suggests Sn(S) at À0.7 V versus RHE was more oxidized than Sn metal, which agreed with the in situ S K-edge spectra 38 ( Figure S11). The trend observed from the Sn L 3 -edge ( Figure 4B) indicates that sulfur-doped Sn possessed a higher oxidation state than Sn NPs after reaction (edge shift indicated by a red arrow), 36,37 consistent with Sn K-edge measurements ( Figure 4C). 35 Sn(S) exhibited a higher oxidation state than Sn NPs after reaction because Sn(S) was more readily oxidized to high valence after exposure to the open circuit potential and air.…”