▎ 摘　　要

NOVELTY - Synthesizing graphene nanosheets at large scale from graphene oxide, comprises synthesizing graphene oxide by modified Hummer's methods, and reducing graphene oxide by cow urine to graphene nanosheets. USE - The method is useful for synthesizing graphene nanosheets (claimed), which are useful in transparent conductive film, chemical sensor, printable ink electronics, LED/organic LED lighting, high speed transistor, energy production and storage, advanced composites and biological applications. ADVANTAGE - The method provides the graphene nanosheets at large scale (claimed) with high quality within short duration of time and with less effort by utilizing simple processing steps (that require low cost chemicals), normal laboratory utensils and cow urine as green reducing agent, while avoiding the need of deionized water or distilled water during reduction process and costly equipments e.g. chemical vapor deposition and arch discharge, hence simple, unique, fast, energy efficient, environmentally friendly and economical.