Electrochemical approach towards the controllable synthesis of nickel nanocones based on the screw dislocation

Abstract

Densely and orderly Ni nanocones with regular spiral textures had been successfully synthesized via a simple and inexpensive electrodeposition process, named two-step electrode-exchange electrodeposition process, in solutions containing ammonium chloride (NH4Cl). Microstructure characterization indicated that Ni nanocones obtained by electrodeposition were pure Ni and were face centre cubic (fcc) structure, which grown mainly along (111) and (220) crystal face. After analysing the morphology, a more optimized possible growth mechanism of Ni nanocones was proposed, in which the stacking microstructure of Ni nanocones was mainly dependent on the stacking direction of Ni2+ on the crystal face (the same direction and the exact opposite direction). Meanwhile, we found that the microstructure of Ni nanocones would be controlled by adjusting the experiment parameters such as concentration of NH4Cl and electrodeposition time, and that the disintegration of complex ions caused NH4+ to gather in large numbers near the cathode and hinder the movement of subsequent complex ions, which made a great change in the microstructure of Ni nanocones.