Metal-organic frameworks derived ZnO-Co3O4 pn heterojunction photocatalyst for the photoelectrochemical detection of sulfadiazine

Semiconductors with abundant surface areas have received substantial attention in the field of sensors, especially for the specific and sensitive detection of molecules. Eco-friendly synthesis of metal oxides pn junction composite with high specific surface area and its photoelectrochemical monitoring on antibiotics have been reported. The ZnO-Co3O4 pn heterojunction composite has successfully been prepared from a metal-organic framework (MOF) as a template, using benzene tricarboxylic acid (BTC) with a one-step calcination process. In research, obtained nanorods like ZnO-Co3O4 pn heterojunction exhibited high conductivity with excellent stability for the facilitated photocatalytic performance towards the photoelectrochemical detection of sulfadiazine (SDZ). Photo-stability and the optical characteristics of the ZnO-Co3O4 heterojunction composite have been analyzed in photocurrent and UV–visible studies. A mechanism of SDZ signaling has been proposed with appropriate band levels derived by Mott-Schottky analysis. The proposed sensor detects SDZ in the range of 0.005–18.5 µM with 1.2 nM as detection limit and exhibits better signaling stability. The applicability of the sensor device has been tested in pork meat, human urine, and river water samples containing SDZ. [Display omitted] •MOF derived ZnO-Co3O4 pn junction composite was synthesized with one step calcination.•ZnO-Co3O4 pn junction has been examined through several characterizations•Promising PEC signaling of SDZ was achieved at low limit.•Possible mechanism for SDZ signaling has been proposed.