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 Hg 2+ 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 Hg 2+ detection by using hollow and porous three-dimensional nano-structured NiCo 2 O 4 with cage-like morphology as an electrode modifier. The NiCo 2 O 4 nanocages (NiCo 2 O 4 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 Hg 2+ . The NiCo 2 O 4 NCs modified glassy carbon electrode (NiCo 2 O 4 NCs/GCE) was demonstrated to be an advantageous and high-performance platform for the electrochemical detection of Hg 2+ with a wide linear range (0.1 nmol/L–3.5 µmol/L) and low detection limit (0.09 nmol/L). Additionally, the NiCo 2 O 4 NCs/GCE was proved to be highly stable, representing it was benign to environment and could be well applied to detect Hg 2+ in real water samples.