Cobalt Phosphide (Co(2)P) with Notable Electrocatalytic Activity Designed for Sensitive and Selective Enzymeless Bioanalysis of Hydrogen Peroxide

In this work, cobalt phosphide nanoparticles (Co(2)P NPs) were prepared by simple and mild hydrothermal method without the use of harmful phosphorous source. The morphological structure and surface component of Co(2)P were characterized by transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy measurements. Considering the excellent electrocatalytic reduction activity and good electrical conductivity of transition-metal phosphide, we fabricated Co(2)P NPs on indium tin oxide (ITO) substrate (Co(2)P/ITO) for H(2)O(2) detection. The Co(2)P/ITO transducer displayed a rapid amperometric response less than 5 s, a broader response range from 0.001 to 10.0 mM and a low detection limit of 0.65 μM. In addition, the non-enzymatic Co(2)P/ITO sensor showed outstanding selectivity, reproducibility, repeatability and stability, all of which qualified the Co(2)P/ITO electrode for quite a reliable and promising biosensor for H(2)O(2) sensing.