In situ assembly of sulfur-doped carbon quantum dots surrounded iron(III) oxide nanocomposite; a novel electrocatalyst for highly sensitive detection of antipsychotic drug olanzapine

Herein, we report the synthesis of sulfur-doped carbon quantum dots (S-CQDs) chemically incorporated with iron oxide nanoparticles (S-CQDs/Fe2O3) using hydrothermal synthesis strategy. The as-synthesized nanocomposite was characterized using powder X-ray diffraction, fourier transform infrared spectroscopy, transmission electron microscope, thermogravimetric analysis, and energy dispersive X-ray spectroscopy. We have analyzed the clear electrochemical kinetics of the S-CQDs/Fe2O3 nanocomposite modified glassy carbon electrode. Addition to this, electrochemical sensing property of S-CQDs/Fe2O3/GCE towards the detection of antipsychotic drug olanzapine (OLZ) was explored. Remarkably, S-CQDs/Fe2O3/GCE has shown the good electrocatalytic activity for OLZ oxidation and also exhibits a very low detection limit and sensitivity of about 0.006 μM and 0.88 μA μM−1 cm−2 respectively. Further, the proposed sensor has applied for the detection of OLZ in urine samples.