Amine-assisted solution approach for the synthesis and growth mechanism of super-long rough-surfaced Cu₇Te₄ nanobelts

Rough-surfaced Cu₇Te₄ nanobelts having a typical length of a few micrometers were fabricated in large quantities for the first time by using dipropylamine (DPrA) as a coordination solvent. We discussed in more detail how to optimize the experimental parameters, such as reaction temperature, the concentration of KOH and solvent, for the fabrication of pure phase, super-long Cu₇Te₄ nanobelts. It is found that solvent and reaction temperature played vital roles in determining the morphologies and homogeneity of the final products, while the concentration of KOH is crucial to be able to determine the phase purity (Cu₇Te ₄ or Cu₇Te₅). Moreover, the formation process of Cu₇Te₄ nanobelts with rough surfaces was believed to include both crystal cleavage by dipropylamine and Ostwald ripening, according to the experimental observations.