Hybrid ternary nanocomposite of N-doped carbon quantum dots@SnO2/multiwall carbon nanotubes: A robust and sensitive electrocatalyst for the detection of antineoplastic agent gallic acid

Abstract

Herein we report the detection of an antineoplastic molecule, gallic acid (GA), by utilizing a hybrid nanocomposite based on N-doped carbon quantum dots decorated tin oxide with multiwall carbon nanotubes (N-CQD@SnO2/MWCNT) for the first time. Initially, the hydrothermal approach was used to synthesize an N-CQD@SnO2 nanocomposite, which further ultrasonically hybridized with MWCNTs to produce the hybrid nanocomposite. Then, the physiochemical properties of the hybrid nanocomposite were characterized using various spectroscopic techniques. The presence of N-CQDs in the SnO2 matrix act as an anchoring point for the hybridization of MWCNTs. The incorporation of N-CQDs in the SnO2 matrix and its hybridization with MWCNT resulted in an extremely low charge transfer resistance for electron transport in the hybrid nanocomposite. Then, using the voltammetric methods, we investigated the analytical performance of an N-CQD@SnO2/MWCNT nanocomposite modified glassy carbon electrode towards the electrochemical detection of GA. The proposed sensor demonstrates excellent analytical results for GA detection, with a low detection limit (0.042 µM), high sensitivity (3.96 µA µM−1 cm−2), good reproducibility, and repeatability. In addition, the sensor was tested with various tea samples, and the observed decent recovery results confirmed its practical usefulness.