Preparation of SnS₂/MWCNTs chemically modified electrode and its electrochemical detection of H₂O₂

Considering the importance of hydrogen peroxide (H₂O₂) rapid detection, a SnS₂/MWCNTs composite was prepared by loading tin disulfide (SnS₂) nanoparticles on a three-dimensional conductive network composed of multi-walled carbon nanotubes (MWCNTs). The obtained SnS₂/MWCNTs composite was used as the modified material to prepare a chemically modified electrode (CME), which was used for the rapid detection of H₂O₂. The morphology and structure of the obtained samples were characterized and analyzed by scanning electron microscopy, X-ray diffraction, and energy-dispersive spectroscopy. The electrochemical performance of the modified electrode was researched by cyclic voltammetry, amperometric i-t curves, and AC impedance techniques. The results show that SnS₂ nanoparticles with a size of about 33 nm are evenly dispersed on the surface of MWCNTs. The obtained SnS₂/MWCNTs-CME has a strong current response to H₂O₂: it has a good linear relationship during the range of 0.248 ~ 16.423 mmol L^-1, and its linear regression equation is I_pa (mA) = (-0.94 ± 0.05) × 10^-2 + (- 0.43 ± 0.06) × 10^-2c (mmol L^-1) (R² = 0.997) with a sensitivity of 87.84 μA mmol^-1 L cm^-2. The corresponding detection limit is 1.04 μmol L^-1 (S/N = 3). At the same time, the SnS₂/MWCNTs-CME has good selectivity, reproducibility, and stability. Graphical abstract Uniformly distributed SnS₂/CNTs composite is used to prepare a chemically modified electrode for H₂O₂ detection. The prepared electrode has a strong electrochemical response to H₂O₂ due to the excellent conductivity and support of CNTs. And the SnS₂/CNTs electrode shows high sensitivity and selectivity for the electrochemical detection of H₂O₂.