Synthesis And Characterization Of Boron Nitride Nanosheets

BN nanosheet is a novel nanomaterial, with the thickness of a few atomic layers.As analogues of grapheme, BN nanosheet has excellent performances, and has greatpotential on the application in the thermal protection and wave transmission device. Inthis study, Hexagonal-BN powder is used as raw material. N, N-dimethyl formamideand isopropyl alcohol are used as a dispersing agent respectively. Using liquidexfoliation method and ball-milling assissted exfoliation to prepare BN nanosheets. Tofumble the process parameters of the liquid exfoliation and to discuss the time impacton the product of the BN nanosheets. TEM, AFM, FT-IR, UV-Vis were utilized tocharacterize the microstructure of BN nanosheets and the performance of the dispersionof BN nanosheets.The results demonstrated that the optimum process of the liquid exfoliation wasthat N, N-dimethyl formamide and isopropyl alcohol were dispersant, and the initialconcentration was2mg/ml, and the time of sonication was10hours, and the dispersionwas centrifuged at6000rpm for half an hour. The thickness of the product of theoptimum process of BN/DMF system was as small as3layers, and the thickness of themajority was from2to4nm. And the thickness of the product of the optimum process ofBN/IPA system was as small as2layers, and the thickness of which was from6to10nm.BN nanosheets which were less that10layers could be more easily with the timeof ball milling. However, the size of the nanosheets decreased.The outcome of the Lamber-Beer Test demonstrated that the absorbance and theconcentration of BN/IPA system met linear relationship, and the extinction coefficientwas tested as α=855.01mlmg^-1m^-1, and the extinction coefficient of the BN/DMF wasα=1200mlmg^-1m^-1.