Morphology-Dependent Electrochemical Properties of CuS Hierarchical Superstructures

Hierarchical superstructures formed by self-assembled nanoparticles exhibit interesting electrochemical properties that can potentially be exploited in Li-ion batteries (LIBs) as possible electrode materials. In this work, we tested two different morphologies of CuS superstructures for electrodes, namely, tubular dandelion-like and ball-like assemblies, both of which are composed of similar small covellite nanoparticles. These two CuS morphologies are characterized by their markedly different electrochemical performances, suggesting that their complex structures/morphologies influence the electrochemical properties. At 1.12 Ag-1, the cells made with CuS tubular structures delivered about 420 mAhg(-1), and at 0.56 Ag-1, the capacity was as high as about 500 mAhg(-1) with good capacity retention. Their ease of preparation and processing, together with good electrochemical performance, make CuS tubular dandelion- like clusters attractive for developing low- cost LIBs based on conversion reactions.