Uniform ordered mesoporous ZnCo2O4 nanospheres for super-sensitive enzyme-free H2O2 biosensing and glucose biofuel cell applications

Uniform, ordered mesoporous ZnCo 2 O 4 (meso-ZnCo 2 O 4 ) nanospheres were successfully synthesized using a sacrificing template method. The meso-ZnCo 2 O 4 nanospheres were used for the first time for H 2 O 2 biosensing and in glucose biofuel cells (GBFCs) as an enzyme mimic. The meso-ZnCo 2 O 4 nanospheres not only exhibited excellent catalytic performance in the H 2 O 2 sensor, achieving a high sensitivity (658.92 μA·mM –1 ·cm –2 ) and low detection limit (0.3 nM at signal-to-noise ratio (S/N) = 3), but also performed as an excellent cathode material in GBFCs, resulting in an open circuit voltage of 0.83 V, maximum power density of 0.32 mW·cm –2 , and limiting current density of 1.32 mA·cm –2 . The preeminent catalytic abilities to H 2 O 2 and glucose may be associated with the large specific surface area of the mesoporous structure in addition to the intrinsic catalytic activity of ZnCo 2 O 4 . These significant findings provide a successful basis for developing methods for the supersensitive detection of H 2 O 2 and enriching catalytic materials for biofuel cells.