IRRADIATION EFFECTS DURING XPS STUDIES OF CU(II) ACTIVATION OF ZINC-SULFIDE

The surfaces of zinc sulphide particles after copper(II) activation at pH 9 have been studied by x-ray photoelectron spectroscopy, The influ ence of x-ray irradiation time on the forms and intensities of the pho toelectron signals from zinc sulphide particles activated at various c opper coverages was investigated, High binding energy components and s atellites of the Cu 2p signals, characteristic of copper(II) hydroxide overlayers, reduced in intensity with increased x-ray exposure, An as sociated reduction in the concentration of surface oxygen was also obs erved. Differential charging analysis and curve fitting reveal the deh ydration of Cu(OH)(2) to CuO, followed by photoreduction of CuO to Cu2 O, No evidence was found for x-ray irradiation enhancement of continue d Cu activation of or diffusion into ZnS.