Synthesis of CuS and Cu1.1Fe1.1S2 crystals and their electrochemical properties

CuS and Cu1.1Fe1.1S2 crystals have been synthesized by the hydrothermal decomposition of Cu or Cu/Fe diethyldithiocarbamate complex obtained by mixing sodium diethyldithiocarbamate, CuCl2 and FeCl3 in absolute ethanol. CuS crystals with a hexagonal structure exhibit irregular particles with an average size of less than 500 nm and rod-shaped morphology with a diameter of less than 100 nm. Cu1.1Fe1.1S2 crystals with a cubic structure contain irregular particles and some rod-shaped structures with length and diameter of about 1 μm and less than 100 nm, respectively. The electrochemical responses of the Cu1.1Fe1.1S2 crystal modified glassy carbon electrode in NaCl and PBS solution show the irreversible and semi-reversible electrochemical process, respectively, which may originate from the NaCl, PBS solution and ascorbic acid. The Cu1.1Fe1.1S2 crystal modified electrodes exhibit definite potential to be used as the electrochemical sensors for detecting cysteine and ascorbic acid.