A three-dimensional bimetallic oxide NiCo2O4 derived from ZIF-67 with a cage-like morphology as an electrochemical platform for Hg2+ detection

Selective detection of toxic Hg2+ is of great significance in the control of the environmental and industrial pollution because it poses serious threat to human health. Herein, we present a differential pulse anodic stripping voltammetric (DPASV) method for Hg2+ detection by using hollow and porous three-dimensional nano-structured NiCo2O4 with cage-like morphology as an electrode modifier. The NiCo2O4 nanocages (NiCo2O4 NCs) derived from ZIF-67 (a cobaltic zeolite imidazole framework) possess large specific surface areas that can provide a large number of adsorption sites for Hg2+. The NiCo2O4 NCs modified glassy carbon electrode (NiCo2O4 NCs/GCE) was demonstrated to be an advantageous and high-performance platform for the electrochemical detection of Hg2+ with a wide linear range (0.1 nmol/L-3.5 mu mol/L) and low detection limit (0.09 nmol/L). Additionally, the NiCo2O4 NCs/GCE was proved to be highly stable, representing it was benign to environment and could be well applied to detect Hg2+ in real water samples.