Fig. 6c shows the Cu PEEM image of Eh modified Cp sample. The Cu
L3-edge spectra of 12 ROI were acquired froma copper PEEM image and
are plotted in Fig. 6ci and cii. The Cu L3-edge spectra revealed the variation
in the copper speciation on different ROI analysed. Spectra represented
in Fig. 6ci show the leading absorption peak near 933.8 eV,attributed to CuI oxidation products (Cu2O). The intensity of the peak
near 932.6 eV, observed under oxidative pulp conditions, was significantly
lower onmost of theROI analysed and the peak at 934.eV become
more prominent. This indicates that the concentration of CuI-oxidation
products increased significantly on the surface of Cp at reductive conditions.
Spectra represented in Fig. 6cii showa prominent absorption peak at 932.8 eV with comparatively less prominent peak at 933.8 eV and indicate,
even at reductive conditions, some of the Cp particle surface
remained less oxidised. A small well resolved peak between 930.0 eV
and 931.2 eV is attributed to CuII oxidation products like CuO [17,
46–48].