Preparation method and application of oxygen-deficient manganese dioxide material

The invention discloses a preparation method and application of an oxygen-deficient manganese dioxide material, and the method comprises the following steps: S1, slowly dropwise adding a manganese sulfate solution into a potassium permanganate solution according to a mass ratio of potassium permanganate to manganese sulfate of 5: 2, uniformly stirring at normal temperature, transferring into a high-pressure reaction kettle, reacting at 90-150 DEG C for 4-8 hours, and cooling to room temperature after the reaction is finished to obtain a manganese dioxide precursor; washing with water, filtering and drying to obtain alpha-MnO2 precursor powder; s2, weighing the alpha-MnO2 precursor powder prepared in the step S1, adding the alpha-MnO2 precursor powder into deionized water, and performing uniform ultrasonic treatment to obtain a suspension; slowly dropwise adding a reducing agent NaBH4 solution into the precursor suspension, wherein the mass ratio of NaBH4 to alpha-MnO2 precursor powder is (1: 10)-(1: 1); the o