Ternary metal oxide nanorods (Ni0.5Cu0.5Co2O4) as efficient positive materials for non-enzymatic glucose sensing and fuel cell application

Abstract

Ternary metal oxide nanorods Ni0·5Cu0·5Co2O4 with high activities for glucose oxidation were prepared through a simple hydrothermal process. The as prepared Ni0.5Cu0.5Co2O4 NRs with uniform aspect ratio were composed of many nanoparticles with diameter less than 10 nm Ni0.5Cu0.5Co2O4 NRs modified glassy carbon electrodes displayed highly improved non-enzymatic glucose sensing (NEGS) performance compared to pure phase NiCo2O4 NRs and CuCo2O4 NRs. The sensitivity of Ni0.5Cu0.5Co2O4 NRs for glucose detection in the lower (5–3000 μM) and higher regional (3000–7000 μM) is 859.31 μA mM−1 cm−2 and 528.81 μA⋅mM−1⋅cm−2, respectively. The limit of detection (LOD) was estimated to be 1.67 μM (S/N = 3). Moreover, the direct glucose fuel cells (DGFCs) equipped with Ni0.5Cu0.5Co2O4 NRs anode also presented much higher power density (413.7 μW cm−2), which is 2 times higher than that of CuCo2O4 NRs (200.2 μW cm−2) and 4.7 times than NiCo2O4 NRs (87.4 μW cm−2). The improved electrochemical performance of Ni0.5Cu0.5Co2O4 NR may benefit from the highly increased charge transfer, which is due to the incorporation of third metal atoms into the spinel lattice of CuCo2O4 or NiCo2O4. The results suggested that Ni0.5Cu0.5Co2O4 NR may be a promising catalyst for application in both NEGS and DGFCs.