Table 1. XPS analysis results of Mo 3d spectra obtained on the CNT-carbon electrodes modified with POM anions.
Binding energy (eV) | Oxidation state |
Area % |
||||
---|---|---|---|---|---|---|
SL-CNT | ESD-NaPOM-CNT | ESD-NH4POM-CNT | ESD-HPOM-CNT | |||
232.0 | Mo 3d5/2 | 5+ | 8.1 | 6.7 | 3.0 | 6.8 |
233.1 | 6+ | 52.0 | 53.4 | 57.0 | 53.4 | |
235.1 | Mo 3d3/2 | 5+ | 5.4 | 4.4 | 2.0 | 4.5 |
236.2 | 6+ | 34.6 | 35.6 | 38.0 | 35.5 | |
FWHM (eV) | 1.6 eV | 1.4 eV | 1.3 eV | 1.4 eV |
CNT, carbon nanotube; ESD, electrospray deposition; FWHM, full-width at half-maximum; POM, polyoxometalate; SL, soft landing; XPS, X-ray photoelectron spectroscopy.