A thin film composition gradient library of the Ni-Cu alloy system is generated through an electrodeposition technique using a complexing citrate electrolyte bath in a modified Hull cell. Energy dispersive X-ray spectroscopy, scanning electron microscopy and automated X-ray diffraction are performed to assess composition, surface morphology, and crystallographic structure of the deposited film as a function of the lateral position on the materials library. The results confirmed deposition of single phase polycrystalline f.c.c. Ni-Cu alloy system with varied lateral composition and lattice parameter, a(fcc) as well. (C) 2014 The Electrochemical Society. All rights reserved.