The preparation method comprises the following steps: respectively weighing
cobalt-containing
nitrate hydrate and 2-methylimidazole, adding the
cobalt-containing
nitrate hydrate and the 2-methylimidazole into
methanol to prepare a solution, pouring the latter solution into the former solution, then adding a
tungsten source, carrying out a stirring reaction at
room temperature, and carrying out suction
filtration, washing and
drying so as to obtain the electrocatalytic
bifunctional material. Centrifuging the obtained product, centrifugally washing the lower precipitate with
methanol,
drying at 50-70 DEG C, and calcining the obtained WS42-ZIF-67 at two stages of different temperatures in an
inert atmosphere; and naturally cooling to obtain the electro-
catalysis bifunctional material with few
layers of WS2 nanosheets anchored on the surface of the
cobalt-
nitrogen-
doped carbon-based polyhedron. The preparation process is simple and efficient, the requirement for equipment is low, and the prepared electro-catalytic
bifunctional material is high in specific surface area, has a specific pore structure and excellent electro-catalytic performance, is used for electro-catalytic
oxygen evolution and
hydrogen evolution reactions and can replace
noble metal catalysts such as Pt and RuO2.