The exceptional properties of graphene and its structural uniqueness can improve the performance of nanocomposites if it can attain the uniform dispersion. Tip sonication assisted graphene solvent dispersion has been emerged as an efficient approach but it can cause significant degradation of graphene structure. This study aimed to evaluate the parametric influence of tip sonication on the characteristics of sp² carbon structure in graphene nanoplatelets by varying the sonication time and respective energy at three different amplitudes (60%, 80% and 100%). The study is essential to identify appropriate parameters so as to achieve high-quality and defect-free graphene with a highly desirable aspect ratio after solvent dispersion for composite reinforcement. Quantitative approach via Raman spectroscopy is used to find the defect ratio and lateral size of graphene evolved under the effect of tip sonication parameters. Results imply that the defect ratio is steady and increases continually with GNPs, along with the transformation to the nano-crystalline stage I up to 60 min sonication at all amplitudes. Exfoliation was clearly observed at all amplitudes together with sheet re-stacking due to considerable size reduction of sheets with large quantity. Finally, considerable GNPs fragmentation occurred during sonication with increased amplitude and time as confirmed by the reduction of sp² domain (La) and flake size. This also validates the formation of edge-type defect in graphene. Convincingly, lower amplitude and time (up to 60 min) produce better results for a low defect content and larger particle size as quantified by Raman analysis.

如果石墨烯可以实现均匀的分散，它的优异性能及其结构的独特性可以改善纳米复合材料的性能。尖端超声处理辅助的石墨烯溶剂分散液已作为一种有效的方法出现，但它可能导致石墨烯结构的显着降解。这项研究旨在评估尖端超声处理对sp ²特性的参数影响。通过以三种不同的幅度（60％，80％和100％）改变超声处理时间和各自的能量来改变石墨烯纳米片中的碳结构。这项研究对于确定合适的参数至关重要，以便在溶剂分散后用于复合增强材料，以非常理想的长宽比获得高质量，无缺陷的石墨烯。通过拉曼光谱的定量方法被用于发现在尖端超声处理参数的作用下石墨烯的缺陷率和横向尺寸。结果表明，缺陷率稳定且随着GNPs的增加而持续增加，并且在所有振幅下，直至60分钟的超声处理，都转变为纳米晶阶段I。由于大量减少了纸张的尺寸，因此在所有振幅下都清楚地观察到了剥落以及纸张的重新堆叠。最后，²域（La）和片状大小。这也证实了石墨烯中边缘型缺陷的形成。令人信服的是，较低的振幅和时间（最长60分钟）对于较低的缺陷含量和较大的粒度（通过拉曼分析定量）可获得更好的结果。