Identification of an anomalous phase in Ni–W electrodeposits

In the present work Ni–W layers electrodeposited from electrolytes based on NiSO 4, Na 2WO 4, citrate, glycine and triethanolamine are characterized with glow discharge optical emission spectroscopy (GD-OES) and X-ray diffraction analysis (XRD). XRD showed the occurrence of an anomalous phase in the deposits, associated with the presence of an appreciable amount of carbon as identified with GD-OES. The anomalous phase is metastable at room temperature and vanishes upon annealing at 550 °C in air.