▎ 摘　　要

NOVELTY - Producing nanosheet, comprises (a) spin-coating the sheet with a graphene oxide (GO) solution, (b) setting a selection area of the sheet, (c) synthesizing vitamin C, natural plant extract fractions, and dimethyl sulfoxide (DMSO) to produce an environmentally friendly basic material and controlling the viscosity, (d) contacting the environmentally friendly basic material with the controlled viscosity to the patterning surface of the patterned poly dimethylsiloxane (PDMS) stamp or performing soft lithography by re-contacting the patterned surface to the selected area of the sheet, and (e) UV-treating or heat treating the sheet at 70-100 degrees C for 30-60 minutes. The environmentally friendly basic material comprises 20-50 pts. wt. natural plant extract fraction and 80-110 pts. wt. DMSO based on 100 pts. wt. vitamin C, and further comprises 1-3 pts. wt. crosslinking agent including 5,5'-bis(oxepan-2-one)(bis- epsilon -caprolactone) and tert-Butylperoxy 2-ethylhexyl carbonate. USE - The method is useful in producing nanosheet for producing reduced graphene oxide sheet. ADVANTAGE - The method is simple process, improves process disadvantages including high temperature and chemical treatment harmful to human body, and provides reduced-fabricated graphene oxide sheet having excellent electrical conductivity and flexibility. DETAILED DESCRIPTION - Producing nanosheet, comprises (a) spin-coating the sheet with a graphene oxide (GO) solution, (b) setting a selection area of the sheet, (c) synthesizing vitamin C, natural plant extract fractions, and dimethyl sulfoxide (DMSO) to produce an environmentally friendly basic material and controlling the viscosity, (d) contacting the environmentally friendly basic material with the controlled viscosity to the patterning surface of the patterned PDMS stamp or performing soft lithography by re-contacting the patterned surface to the selected area of the sheet, and (e) UV-treating or heat treating the sheet at 70-100 degrees C for 30-60 minutes. The environmentally friendly basic material comprises 20-50 pts. wt. natural plant extract fraction and 80-110 pts. wt. DMSO based on 100 pts. wt. vitamin C, and further comprises 1-3 pts. wt. crosslinking agent including 5,5'-bis(oxepan-2-one)(bis- epsilon -caprolactone), tert-Butylperoxy 2-ethylhexyl carbonate, tert-butyl peroxyneoheptanoate, spiro-bis-dimethylene-carbonate and hydroxyethyl methacrylate, and hydroxy-carboxylic acid comprising glycolic acid, lactic acid, malic acid, citric acid and/or tartaric acid. The natural plant extract fraction is prepared by (i) preparing a mixed powder obtained by mixing the dried citron powder and the dried lime powder in a weight ratio of 1:2-3; (ii) putting the mixed powder into a jar, then adding and mixing water and fermentation strain culture in the jar, sealing, and fermenting at 20-35 degrees C for 4-5 weeks to obtain a fermented broth; (iii) filtering the fermentation broth to obtain a liquid concentrated fermented product, and drying to obtain a dried concentrated fermented powder; (iv) preparing a mixed solution of 100- 140 pts. wt. extraction solvent containing butanol and ethanol in a weight ratio of 1: 2-3 with respect to 100 pts. wt. concentrated fermented powder; (v) obtaining an ultrasonic extract by applying ultrasonic waves at a frequency of 5-10 kHz for 15-20 minutes and then leaving the mixed solution at 20-35 degrees C for 18-24 hours; (vi) fractionating the obtained ultrasonic extract with ethyl acetate to obtain a fraction; and (vii) obtaining a purified fraction using silica gel column chromatography for the fraction. The citron powder includes a pulverized product obtained by pulverizing dried citron seeds and dried citron shells, and the lime powder includes a pulverized product obtained by pulverizing dried lime seeds and dried lime peels. The fermented product is obtained by mixing 40-60 pts. wt. water and 100 pts. wt. mixed powder and 0.5-1 pts. wt. fermentation strain culture medium containing 50-100 g mixed powder obtained by mixing 1 l Luria-Bertani variable medium and dried citron powder and dried lime powder in a weight ratio of 1:2-3. The fermentation strain culture medium is prepared by inoculating fermented strain of 1x 106 -1x 107 CFU/1 l lactic acid bacteria culture medium and leaving it at 25-30 degrees C for 18-36 hours. The lactic acid bacteria culture medium contains 60-80 g mixed powder including the dried citron powder and the dried lime powder. The fermentation strain includes Lactobacillus fermentum, Lactobacillus plantarum Lactobacillus plantarum and Leuconostoc mesenteroides containing yeast.