Influence of Fatty Acid Alkyl Chain Length on Anisotropy of Copper Nitride Nano-Crystallites

My group developed a simple method to prepare copper nitride fine particles from copper carboxylate in a solvent of long-chain alcohols without the use of high temperatures or high pressures. By selecting copper acetate or copper decanoate as the copper source, my group demonstrated that the morphology of the copper nitride fine particles varied between cubic and plate-like, respectively. Although a hypothesis was proposed to explain the influence of the length of the alkyl chain on the copper decanoate, it is uncertain how much the chain length influences the shape of the fine particles. In this work, I demonstrated the effect of the length of the alkyl chain on particle shape by preparing fine particles from a series of copper sources with different alky chain lengths and characterizing the particles with x-ray diffractometry (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The main findings were as follows: (1) the fine particles were plate-like when the alkyl chain length exceeded 5; (2) the aspect ratio of the plate-like particles increased as the alkyl chain length increased; and (3) growth of the (110) and (111) planes of the copper nitride crystal were selectively inhibited.