Facile synthesis of highly dispersed silica-silver core-shell nanospheres for enzymeless hydrogen peroxide detection

摘要

Highly-dispersed 17± 2-nm SiO_2 nanospheres were obtained by a modified St?ber method and then used as material precursors in a green chemistry process for obtaining SiO_2-Ag core-shell nanocomposites with the shell thickness of 1.5 nm. In addition, an enzymeless SiO _2-Ag core-shell modified electrode was fabricated and used for the first time to detect H_2O_2. The modified electrode has a fast amperometric response of <2 s at low detection limit of 0.1 M. The linear range of H_2O_2 detection is estimated to be from 0.25μM to 6.7 mM with a determination coefficient R~2 of >0.99.