Selective au electrodeposition on au nanoparticles embedded in carbon film electrode for Se(IV) detection

Abstract

We report the ppb level detection of selenium by anodic stripping voltammetry (ASV) using finely dispersed gold nanoparticles (grown Au NPs) electrodeposited on sputter-deposited Au NPs embedded in carbon film electrodes. The Au NP-embedded carbon (AuNP-C) films were fabricated by the unbalanced magnetron (UBM) cosputtering of Au and carbon targets. The difference in overpotential between gold and carbon surfaces allows the selective deposition of gold ions only on the exposed Au parts of a AuNP-C film. As a result, we could successfully realize the highly dense deposition of Au NPs at the electrode surface without forming a Au film. By ASV with the developed electrode, we successfully increased the stripping current of selenium while maintaining the stable response derived from selectively grown Au NP structures.