Role of reducing agent and self-sacrificed copper-thiourea complex in the synthesis of precisely controlled Cu2−xS microtubes

In this study, a simple, cost-effective thermolysis route to produce single phase, stoichiometric, hollow Cu<inf>2−x</inf>S microtubes of varied composition by using Cu(tu)Cl·0.5H<inf>2</inf>O as a self-sacrificed template is devised. Here, the concentration of the reducing agent (i.e., Na<inf>2</inf>SO<inf>3</inf>) is precisely controlled to obtain these Cu<inf>2−x</inf>S microtubes, which are confirmed by using XRD, EDX and FESEM. The optical absorption as well as the optical band gap of these compounds are found to be strongly influenced by their composition. Finally, the mechanism of formation of these precisely controlled compounds and direct impact of the shape of the self-sacrificed template on the ultimate tubular morphology of Cu<inf>2−x</inf>S is discussed.