Investigation on quenching effect of TiVC MXene quantum dots on the enhanced TiO2 ECL by MWCNTs and its sensing application for chloramphenicol detection

Cathodic ECL of TiO 2 was greatly enhanced by carboxylated MWCNTs. • TiVC MXene QDs were loaded onto MOF to form stable nanocomposite. • TiVC/MOF nanocomposite exhibited inhibiting effect on the cathodic ECL of TiO 2 . • An ECL sensor for chloramphenicol was fabricated based on its inhibiting effect. In this study, TiO 2 nanoparticles were employed as novel luminophore to obtain cathodic electrochemiluminescence (ECL) signal in the presence of K 2 S 2 O 8 under neutral aqueous condition. Carboxylated multi-walled carbon nanotubes (f-MWCNTs) served as co-reactant accelerators to facilitate the reduction of K 2 S 2 O 8 , resulting in greatly enhanced cathodic ECL signal. TiVC MXene quantum dots (TiVC QDs) were loaded onto MOF to form stable nanocomposite (TiVC/MOF) which could effectively suppress the cathodic ECL emission by blocking interfacial electron transfer and consuming SO 4 •− via chemical reaction. Based on the inhibiting effect of TiVC/MOF nanocomposite, an “off-on” mode ECL sensor was fabricated for the sensitive detection of chloramphenicol (CAP). Under the optimal condition, the proposed sensor exhibited a linear range of 0.1 μM-6 μM with a detection limit of 3.62 nM. Moreover, the ECL sensor showed satisfactory analytical performance in real samples, offering a reliable strategy for the sensitive detection of CAP. Carboxylated multi-walled carbon nanotubes (f-MWCNTs) could act as co-reactant accelerators to greatly enhance the cathodic ECL of TiO 2 nanoparticles. TiVC MXene QDs were loaded onto MOF to form stable nanocomposite (TiVC/MOF) which could effectively suppress the cathodic ECL emission. Based on the inhibiting effect of TiVC/MOF nanocomposite, an “off-on” mode ECL sensor was fabricated for the sensitive detection of chloramphenicol (CAP). The ECL sensor showed satisfactory analytical performance in real samples, offering a reliable strategy for the sensitive detection of CAP. Download: Download high-res image (178KB) Download: Download full-size image