Evolution of SnO2 nanoparticles for the electrochemical sensing of dopamine including photocatalytic toxic dyes degradation

In the present study, SnO₂ nanoparticles were synthesized, and their structural features were evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and transmission electron microscopy (TEM) techniques. Modified electrodes (MCPE) were prepared and utilized to access the electrochemical behaviour of dopamine. This study was conducted in a phosphate buffer solution with a pH value of 7.2. The results indicate that the modified carbon paste electrode (MCPE), with a high active surface area, exhibited excellent electrochemical sensing properties and demonstrated good reproducibility and high sensitivity for the electrochemical determination of DA. Potentially interfering compounds were tested at the surface of the proposed sensor, confirming that, they did not interfere with the determination of DA under optimum condition. Additionally, the photocatalytic properties of SnO₂ were evaluated in degradation of cationic and anionic dyes. It was concluded that the higher photocatalytic activity in SnO₂ nanocomposites was attributed to their porosity and high surface area.