A facile synthesis of reduced Co3O4 nanoparticles with enhanced Electrocatalytic activity for oxygen evolution
By Liu, Yan-Ru; Han, Guan-Qun; Li, Xiao; Dong, Bin; Shang, Xiao; Hu, Wen-Hui; Chai, Yong-Ming; Liu, Yun-Qi; Liu, Chen-Guang
Published in International Journal of Hydrogen Energy
2016
Abstract
Abstract Novel reduced Co3O4 nanoparticles as electrocatalyst have been synthesized by a facile NaBH4 reduction treatment. Microwave-assisted Co3(CH3COO)5(OH) has been used as precursor to increase the surface area of Co3O4. The as-prepared samples were characterized by X-ray diffraction (XRD), Transmission electron microscope (TEM) and scanning electron microscope (SEM). The original Co3O4 (OCo3O4) nanoparticles have been prepared by annealing of Co3(CH3COO)5(OH). After treatment by NaBH4, {OCo3O4} transforms into the reduced Co3O4 (RCo3O4). Electrochemical measurements for oxygen evolution reaction (OER) show that {RCo3O4} has more excellent electrocatalytic activity with the lower onset potential of 1.5 V (vs. RHE) and larger current density by over 6.4 times than that of OCo3O4, which may be ascribed to the more oxygen vacancies derived from reduction treatment of NaBH4. Therefore, increasing the number of oxygen vacancies of metal oxides by facile reduction treatment may be a promising way to prepare the efficient electrocatalysts for OER.