Abstract
Cobalt-encapsulated in nitrogen-doped carbon nanotubes (Co-NCNT) were prepared by hydrothermal method. CoCl2·6H2O and graphitic carbon nitride (g-C3N4) were used as raw material. Samples containing such defective structures were synthesized by hydrothermal methods, while there is an excellent synergistic effect between cobalt nanoparticles and carbon nanotubes on hydrogen evolution reaction (HER). In order to improving the HER performance, different samples were fabricated by changing the molar ratio of raw materials and pyrolysis temperature. The results show that Co-NCNT has the best HER performances at the ratio of CoCl2·6H2O and g-C3N4 (1:7) when the pyrolysis temperature reached 700 °C. The overpotential has reached 285 mV when the current density is 10 mA·cm−2, the Tafel slope of the sample is 103 mV·dec−1.