Method for producing graphitic zinc oxide-carbon nitride (ZnO-g-C₃N₄) nanocomposites from used alkaline batteries.

Abstract

The invention relates to a method for producing graphitic zinc oxide-carbon nitride (ZnO-g-C3N4) nanocomposites from used alkaline batteries. The method includes: recovering zinc oxide powder from used alkaline batteries; treating the powder with an ethanol-water mixture under ultrasonic treatment, washing, and drying to obtain zinc oxide-containing material without using acid to separate zinc or manganese and without separating manganese as an independent compound; synthesizing g-C3N4 by urea pyrolysis; dispersing g-C3N4 in ethanol by ultrasonication; mixing the zinc oxide-containing material with the g-C3N4 dispersion system at room temperature in a mass ratio of 3:1 to 6:1; and separating and drying to obtain the nanocomposite material. After the mixing step, the method does not involve sintering, hydrothermal treatment, microwave treatment, heat treatment, or any processing steps at temperatures greater than 100°C to form the nanocomposite material.The resulting material has a porous, layered, and / or mesoporous structure, capable of absorbing visible light and exhibiting high photocatalytic activity in the degradation of methylene blue and crystal violet. The method has the advantages of being simple, energy-efficient, limiting the use of harsh chemicals, and effectively utilizing alkaline battery waste.