▎ 摘　　要

NOVELTY - Composite material comprises 0.05-1% graphene, 5-30% nitride oxide and 69-94% bismuth oxyiodide. USE - The composite material is useful as photocatalytic material for inactivating Gram-negative bacteria, Gram-positive bacteria and other microorganisms, preferably Escherichia coli, Staphylococcus aureus and Candida albicans (all claimed ). ADVANTAGE - The method has simple and easy preparation; and is economical and the composite material has excellent visible light. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the composite material, comprising (ii) adding urea into muffle furnace to calcine the product after naturally cooling, grinding the prepared carbon nitride, (ii) dissolving potassium iodide in the distilled water to prepare the potassium iodide solution, adding oxidized graphene solution into the potassium iodide solution and the step (i) the prepared nitride, ultrasonically dispersing to obtain suspension solution, (iii) dissolving bismuth nitrate pentahydrate in ethylene glycol to prepare pentahydrate, adding suspension solution into pentahydrate bismuth nitrate glycol solution, stirring, washing using water, drying and grinding.