A facile and ultrasensitive photoelectrochemical sensor for copper ions using in-situ electrodeposition of cuprous oxide

A new and facile photoelectrochemical sensor using in situ electrodeposition of cuprous oxide for copper ions was first constructed. The proposed method is based on the enhanced photocurrent produced by the electrodeposited cubic Cu2O with the increasement of the concentration of copper ions. The prepared films of cubic Cu2O were successfully characterized by scanning electron microscopy, X-ray diffractometry, and ultraviolet–visible spectroscopy. The fabricated photoelectrochemical sensor showed good performances with a rapid response, facile preparation, excellent stability, a wide linear range (1 × 10−11–1 × 10−3 mol L−1), and a low limit of detection (3.33 pmol L−1) at 3 signal-to-noise ratio. It has been successfully applied to the detection of copper ions in environment water sample, which is consistent with the results by inductively coupled plasma-mass spectroscopy. It opens up a novel insitu electrodeposited photoelectrochemical sensing method for metal ions.