Positive electrode material and preparation method therefor, alkaline secondary battery

A positive electrode material, comprising a core material and a coating layer coated on the surface of the core material, the core material comprises nickel hydroxide, and the coating layer comprises a tetravalent cobalt compound;

• and based on the weight of the coating layer, the content of the tetravalent cobalt compound is no less than 45 wt %,
• wherein based on the weight of the coating layer, the content of the tetravalent cobalt compound is 67 wt %-76 wt %;
• wherein the coating layer further comprises at least one of γ-CoOOH and β-CoOOH, wherein when the coating layer includes γ-CoOOH, the cobalt contained in γ-CoOOH is not at a valence of +4.