Hollow carbon sphere supported Ag nanoparticles for promoting electrocatalytic performance of dopamine sensing

•Mesoporous hollow carbon sphere (HCS) was obtained by self-assembly and employed SiO2 as a template.•An enhanced sensor of dopamine was developed using Ag@HCSs nanocomposites modified electrode.•Ag@HCSs acts as an excellent sensing material for non-enzymatic dopamine detection. Nonenzyme electrochemical sensor of dopamine based on various highly active nanomaterials has attracted enormous attention. In this paper, hollow carbon spheres (HCSs) were chosen as the catalyst supports due to its abundant mass transport channels, large specific surface area and electronic properties. Ag nanoparticles decorated mesoporous HCSs were synthesised by employing sodium borohydride as reductant. The Ag nanoparticles attached HCSs with an average diameter of ˜ 6 nm. The BET surface area and pore width of HCSs are 568.62 m2 g−1, 4.3 nm, respectively. A high-performance dopamine sensor was fabricated based on a glassy carbon electrode modified with Ag@HCSs nanocomposites. In the electrocatalytic experiments, the relevant kinetic parameters were calculated (α = 0.63, ks = 0.32 s−1), which proved that the nanocomposites has a high catalytic efficiency in promoting the electron transfer kinetics of dopamine at the modified GCE. Dopamine can be detected by amperometry (at a typical working potential of 0.2 V vs. SCE) with a detection limit of 0.6 μM, over two wide linear ranges (3 μM - 2 mM and 2 mM–7 mM), and with high sensitivities (757 μA mM−1 cm-2 and 315 μA mM−1 cm-2), respectively. In addition, the sensor also showed good selectivity, stability and repeatability.