Anomalous codeposition mechanism of Co-Ni alloy nanowires

The anomalous codeposition of Co-Ni nanowires occurs at potentials from −0.9 V to −1.6 V while the normal codeposition occurs at −3.0 V. We propose that hindrance of crystallization of Ni atoms can be responsible for the anomalous codeposition. The anomalous codeposition can be attributed to formation of hcp phase in deposition as the limited solubility of Ni in the hcp Co-Ni phase can block the deposition of Ni atoms onto the hcp lattice. The normal codeposition can be related to formation of fcc phase in deposition as the complete solubility of Ni in the fcc Co-Ni phase can lead to no hindrance of crystallization of Ni atoms. - Highlights: • The anomalous codeposition of Co-Ni nanowires occurs at lower potentials. • Higher potentials lead to the normal codeposition of Co-Ni nanowires. • Hindrance of crystallization can be responsible for the anomalous codeposition. • The limited solubility of Ni in hcp phase can inhibit the deposition of Ni atoms.