Condensation coefficients of noble metals on polymers: a novel method of determination by x-ray photoelectron spectroscopy

We developed a method to determine condensation coefficients, C, of noble m etals on polymer surfaces and to determine cluster sizes by means of XPS on ly, or in combination with transmission electron microscopy (TEM), The surf ace concentration of the adatoms was determined using a mathematical correc tion of the XPS intensity that takes into account cluster growth of the nob le metals on the polymer surfaces. We establish our method with experimenta l results of C for Cu and Ag on pyromellitic dianhydride (PMDA)-4,4'-oxydia niline (ODA) polyimide, bisphenol-a polycarbonate, trimethylcyclohexane bis phenol-A polycarbonate, polystyrene and Teflon AF 1601, Values of C for Ag determined with the XPS method agree well with those of radiotracer measure ments. The condensation coefficient varies by three orders of magnitude fro m 1 to 0.002, depending on the deposition parameters and properties of the adsorbents. The method can be applied in general to investigate the deposit ion of non-wetting metals on solid surfaces. Copyright (C) 2000 John Wiley & Sons, Ltd.