▎ 摘　　要

NOVELTY - Preparing composite visible light-responsive photocatalyst material comprises e.g. (i) taking urea and melamine to dissolve, drying, grinding, heating to obtain block graphitic carbon nitrides (g-C3N4), grinding the block g-C3N4, heating to obtain g-C3N4 powder, ultrasonically peeling the g-C3N4 powder in isopropanol, centrifuging and drying to obtain SL g-C3N4, (ii) adding graphene oxide (GO) into dimethylformamide and sonicating to make GO fully dispersed, adding ethylenediamine and N,N'-dicyclohexylcarbodiimide into the above reaction mixture, sonicating and placing in a 75 degrees C water bath for 8 hours, adding absolute ethanol, removing the supernatant, centrifuging, washing, dialyzing, and drying to obtain aminated graphene oxide (NGO), (iii) taking 100 mg SL g-C3N4 and NGO of carbon nitride, adding water and ethanol solution, sonicating for 1-3 hours, centrifuging, washing, and drying the product at 60 degrees C to obtain SL g-C3N4/NGO heterojunction. USE - The photocatalyst material is useful in water treatment (claimed). ADVANTAGE - The method: has improved visible light catalytic activity and stability of the composite photocatalyst material. DETAILED DESCRIPTION - Preparing composite visible light-responsive photocatalyst material comprises (i) taking urea and melamine to dissolve in a mass ratio of 6:1, drying the mixed solution at 80 degrees C, grinding the obtained powder and placing in an alumina crucible, placing the crucible in a muffle furnace, heating at 250-350 degrees C at a rate of 10-15 degrees C/minutes and maintaining for 60-100 minutes to obtain block graphitic carbon nitrides (g-C3N4), grinding the block g-C3N4, adding into a crucible, placing the crucible in a muffle furnace for secondary calcination, heating at 350-520 degrees C at a rate of 10-15 degrees C/minutes for 60-100 minutes to obtain g-C3N4 powder, ultrasonically peeling the g-C3N4 powder in isopropanol for 1-3 hours, centrifuging and drying to obtain nano-sheet layer g-C3N4 as SL g-C3N4, (ii) adding 50-150 mg graphene oxide (GO) into 50-150 ml dimethylformamide and sonicating for 60-100 minutes to make GO fully dispersed, adding 5-20 g ethylenediamine and 0.5-3 g N,N'-dicyclohexylcarbodiimide into the above reaction mixture, sonicating for 60 minutes and placing in a 75 degrees C water bath for 8 hours, adding 100 ml absolute ethanol into the above reaction mixture, allowing to stand for overnight, removing the supernatant, repeatedly centrifuging the reaction mixture, washing with absolute ethanol and deionized water, and dialyzing for 24 hours in a dialysis bag, drying the dialysis sample in a freeze dryer to obtain aminated graphene oxide (NGO), (iii) taking 100 mg SL g-C3N4 and 1 wt.%, 2 wt.%, 3 wt.%, 4 wt.% or 5 wt.% NGO of carbon nitride, adding water and ethanol solution with a volume ratio of 2:1-4:1, sonicating for 1-3 hours, centrifuging the solid product, washing with water and ethanol repeatedly, and drying the product at 60 degrees C to obtain SL g-C3N4/NGO heterojunction. An INDEPENDENT CLAIM is also included for composite visible light-responsive photocatalyst material prepared by above method.