A very facile, low temperature, one-step route to in situ fabricate copper sulfide nanosheet thin films

CuS nanosheet thin films with large areas were synthesized in situ on copper substrates through a facile, one-step treatment of copper foil and sulfur powder in the presence of N, N-dimethylformamide (DMF) at low temperature (60 degrees C or less). Compared with the previous reported solvothermal approach, the current low temperature route is simpler, low cost and low energy consumption. The effects of the reaction temperature on the synthesis and the optical property of CuS nanosheet films were investigated. The resulting CuS nanosheet films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and UV-vis spectrometer. In this study, we also demonstrated this method to prepare copper sulfide nanosheet films on ground-glass and indium tin oxide glass (ITO) substrates. We found that perfect nanosheet crystals could be obtained in all cases. The growth mechanism of CuS nanosheet-based films was proposed. The current method may open up a new way to prepare thin films of metal sulfide at low temperatures.