Composite with synergistic effect of adsorption and visible light catalytic degradation and preparation method and application thereof

A preparation method of a composite with synergistic effect of adsorption and visible light catalytic degradation, which comprises the steps as below:

• 1) preparation of activated carbon fibers with bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized on:
• dissolving bismuth nitrate pentahydrate and activated carbon fiber in solvent to obtain solution A;
• dissolving potassium iodide and potassium chloride in solvent to obtain solution B;
• adding solution B to solution A under stirring, mixing evenly, then moving the reaction mixture to a hydrothermal reactor and reacting for 10 to 16 hours at 120 to 180° C., after the completion of the reaction, the reaction vessel is taken out, cooled and opened, and the fibrous product is collected by filtration, washed and dried to obtain bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite;
• wherein,
• the molar ratio of bismuth nitrate pentahydrate, potassium iodide and potassium chloride is 1:x:(1−x), and 0<x<1;
• the ratio of bismuth nitrate pentahydrate and activated carbon fiber is 1 mol:
• 25˜50 g;
• 2) the graft of polyethyleneimine:
• dispersing the bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite obtained in step 1) in solvent, adding silane coupling agent, reacting for 4 to 8 hours at 60 to 80° C. while stirring, then adding polyethyleneimine solution, continue stirring to react for 4 to 6 hours, after the reaction, the mixture is cooled and filtered to collect the fibrous product, washed and dried to obtain a composite material with synergistic effect of adsorption and visible light catalytic degradation;
• wherein,
• the ratio of said bismuth oxyiodide/bismuth oxychloride composite nanoparticles immobilized activated carbon fiber composite, silane coupling agent and polyethyleneimine solution is 50 mg:50 μL:1˜10 g.