CdS nanocrystals, which were surface modified by poly (nickel dithioxamide) n, were prepared and characterized. TEM image showed that the shape and the outward aspect of the modified CdS sample were essentially the same as those of the original material and no impurities were found. The characteristic IR peaks at 1 513 cm-1 and 870 cm-1 confirmed the success in assembling n on the surface of CdS. For XPS spectra, the characteristic bands of Ni2p3/2 and Ni2p1/2 appeared at 856 eV and 877 eV indicating the nickel in Ni(Ⅱ)oxidation state. The solid state electronic spectra showed the improvement in surface energy gap, which was changed from 2.38 eV to below 1.91 eV.
