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

► CuS and Cu1.1Fe1.1S2 crystals were prepared by the hydrothermal decomposition process. ► The Cu1.1Fe1.1S2 modified electrode exhibits potential for cysteine and ascorbic acid. ► The Cu1.1Fe1.1S2 modified electrode may be used as electrochemical sensors.