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

Publication date: 1 July 2019Source: Sensors and Actuators B: Chemical, Volume 290Author(s): Xinjin Zhang, Jianbin ZhengAbstractNonenzyme 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.
Source: Sensors and Actuators B: Chemical - Category: Chemistry Source Type: research