▎ 摘　　要

NOVELTY - Preparing graphene nano-roll comprises (i) preparing graphene coated nano-particle, sequentially adding concentrated sulfuric acid, flake graphite and potassium nitrate, adding potassium permanganate into the solution, stirring, adding deionized water into the solution, heating to obtain a solution-A, centrifuging, adding separated graphite oxide of hydrazine hydrate, adding deionized water and mixed solution into the reaction vessel, preparing zirconium oxychloride aqueous solution, adding lactic acid into the prepared solution, placing the inner liner in a reaction vessel, centrifuging, washing, and drying, ultrasonically dispersing the reduced graphene oxide in anhydrous ethanol, and (ii) spin-coating the reduced graphene oxide coated nano-zirconia particles of anhydrous ethanol dispersion, drying, placing the dried stainless steel piece on a friction tester, and ultrasonically dispersing. USE - The method is useful for preparing graphene nano-roll. ADVANTAGE - The method has great selectivity, and short cycle, the separation of the obtained nano-rolls and the nano-particle is relatively easy, is simple and economical. DETAILED DESCRIPTION - Preparing graphene nano-roll comprises (i) preparing graphene coated nano-particle, (i.a) mixed solution consisting of flake graphite, potassium nitrate and concentrated sulfuric acid, sequentially adding concentrated sulfuric acid, flake graphite and potassium nitrate, adding potassium permanganate into the solution and stirring at 40 degrees C for 3 hours, adding deionized water into the solution, and heating to 65-80 degrees C, at a speed of 800-1000 rotations/minute for 20-90 minutes to obtain a solution-A, adding hydrogen peroxide into deionized water, stirring to obtain hydrogen peroxide solution, slowly pouring the solution-A into a hydrogen peroxide solution, stirring evenly to adjust the pH value to 5-6 with sodium hydroxide to obtain a solution-B, centrifuging at a speed of 8000 rotations/minute for 30 minutes to obtain liquid and solid separation phase, and centrifuging the 8000 rotations/minute for 25 minutes with an ethanol solution to remove residual impurities to obtain graphite oxide, (i.b) adding 8 wt.% separated graphite oxide of hydrazine hydrate, stirring for 2-4 hours, adding deionized water and mixed solution into the reaction vessel, and reducing graphene oxide by reacting at 80 degrees C for 800 minutes, (i.c) preparing 0.3 mol/l zirconium oxychloride aqueous solution by zirconium oxychloride octahydrate powder and deionized water, adding lactic acid into the prepared solution, stirring evenly with a magnetic stirrer, adding yttrium nitrate hexahydrate powder and erbium chloride powder, the obtained mixed solution has a yttrium of 0.02 mol/l and an erbium of 0.08 mol/l, adjusting the pH of the mixed solution by sodium hydroxide, transferring the mixed solution into a polytetrafluoroethylene inner liner, placing the inner liner in a reaction vessel and reacting at 160 degrees C for 24 hours, centrifuging the reaction solution, washing with distilled water and absolute ethanol, and drying at 80 degrees C to obtain erbium doped yttrium-stabilized nano zirconium dioxide powder, (i.d) ultrasonically dispersing the reduced graphene oxide in anhydrous ethanol, adding the prepared rare earth doped nano zirconia powder in a mass ratio 1:1, and ultrasonically dispersing the mixture to obtain an anhydrous ethanol dispersion of reduced graphene oxide coated nano zirconia particles, and (ii) preparing graphene nano-rolls by friction shear method for laser texturing of stainless steel substrate surface, spin-coating the reduced graphene oxide coated nano-zirconia particles of anhydrous ethanol dispersion on a stainless steel substrate at a speed of 1000 rotations/minutes for 30 seconds, drying in a vacuum drying oven at 80 degrees C, placing the dried stainless steel piece on a friction tester of 6 mm silicon nitride ball, loading 100 g, at a speed of 200 rotations/minute for 20-30 minutes to obtain abrasive, and ultrasonically dispersing in absolute ethanol.