Layer-by-layer construction of caterpillar-like reduced graphene oxide-poly(aniline-co-o-aminophenol)-Pd nanofiber on glassy carbon electrode and its application as a bromate sensor

An electrochemical reduced graphene oxide/poly(aniline-co-o-aminophenol)/palladium (ERGO-PANOA-Pd) nanocomposite modified glassy carbon (GC) electrode was fabricated by electrochemical reduction of GO, electrochemical polymerization of PANOA and electrochemical deposition of Pd nanoparticles, respectively. TEM and SEM display a well-defined nanofiber with diameters of 60-70 nm of PANOA synthesized on ERGO. After deposition of Pd nanoparticles, the ERGO-PANOA-Pd shows a caterpillar-like nanofiber structure. The ERGO-PANOA-Pd modified GC electrode exhibits excellent electrochemical activity in a 0.2 M H2SO4 compared to the ERGO and ERGO-PANOA modified GC electrode. CV results also show the as-prepared electrode has good electrocatalytic behavior to bromate in a pH 4.0 PBS. Under the optimal conditions, the ERGO-PANOA-Pd modified GC electrode can be used to determine bromate concentration in a wide linear range of 4 and 840 μM with a detection limit of 1 μM. The sensitivity of the electrode was 33.2 nA μM−1. The proposed sensor has good anti-interference property.