Solution growth of Cu2S nanowalls on Cu substrates and their characterization

Abstract A simple method of preparing Cu 2 S nanowalls was presented by immersing Cu substrates into a Na 2 S/HCl solution. X-ray diffraction (XRD) analysis revealed the formation of the monoclinic phase of Cu 2 S nanostructures on Cu substrates, presenting a thickness of less than 100 nm and a height of several micrometers (called nanowalls) from the scanning electron microscopic (SEM) images. Moreover, the transmission electron microscopy (TEM) and X-ray energy dispersive spectrometry (EDS) characterizations indicated that these Cu 2 S nanowalls were thinner near the sheet edge and had voids inside the sheets supposedly due to the etching reaction by Na 2 S/HCl. Cu substrates with Cu 2 S nanowalls were found to exhibit extinguished hydrophobicity (> 110°) resulting from their rough surfaces based on the water contact angle measurements. Electrical current–voltage analysis indicated the formation of a Schottky barrier at the Cu 2 S/Cu interface.