▎ 摘　　要

NOVELTY - A low-defect graphene-boron oxide nanocrystalline composite material is prepared by taking graphite sheet and boric acid at mass ratio of 2:1-6:1, adding N-methylpyrrolidone to solid content of 0.1-0.8 mg/mL, stripping ultrasonically with power of 100-125 W, centrifuging for 45 minutes at speed of 1000 revolutions/minute, stripping ultrasonically at power of 100-125 W, and centrifuging for 45 minutes at speed of 1500 revolutions/minute. USE - Method for preparing low-defect graphene-boron oxide nanocrystalline composite material (claimed). ADVANTAGE - The process has mild operation conditions, simple operational techniques, and low energy consumption.