Graphene has a wide range of applications in the fields of electronic devices, sensors, batteries / supercapacitors, catalyst carriers, and graphene-based composite materials due to its excellent mechanical, thermal, electrical, and large specific surface areas. The low-cost and macro-scale preparation of graphene is the premise and key to its wide application. Therefore, the efficient preparation of graphene based on efficient stripping of graphite on a large scale has been a difficult problem for researchers to solve. Recently, the research group of Professor Zhao Yaping of Shanghai Jiaotong University has used the established supercritical carbon dioxide stripping technology to efficiently prepare graphene and construct one-dimensional graphene rolls based on its self-assembly to obtain a number of new research results. The scale application of graphene and one-dimensional The study of graphene rolls has important practical application value and academic significance.
Highly efficient production of graphene by an ultrasound coupled with a shear mixer in supercritical CO2 was titled "Industrial & Engineering Chemistry" Research "was published as a cover article (December 12, 2018 Volume 57, Issue 49 Pages 16537-17032). Ultrasound generates active edges on graphite particles, and at the same time, the graphite is sheared and peeled from the active edges, which greatly improves the stripping efficiency of graphene.
Using the stripped graphene as a raw material, the team for the first time established a new method for graphene to mass-produce one-dimensional graphene nanoscrolls through self-assembly. A graphene roll is a new type of carbon material with a multi-walled carbon nanotube structure similar to a multi-walled carbon nanotube structure formed by spirally winding a two-dimensional graphene sheet. The one-dimensional tubular nano-structured carbon material has an unclosed special topology structure with ports and edge openings. Graphene coils not only inherit the excellent chemical, physical, and electrical properties of graphene and carbon tubes, but also have special properties that are different from them, which has become a hot topic of recent research. The method established by the team is simple and has high self-assembly efficiency, which provides the basis for mass production of graphene nano rolls and their applications. The work was published in Scientific Reports under the title A facile and universal approach for quantity production of high-quality nanoscrolls with high-yield from two-dimensional nanosheets (2018, 8, 1: 15262.).
The team's further research found that under certain conditions, the formed one-dimensional graphene nanovolumes can be reversibly unfolded into graphene, realizing the reversible conversion between two-dimensional graphene and one-dimensional graphene nanorolls. The results provided new ideas for constructing one-dimensional materials from two-dimensional materials, and laid the foundation for the stable storage and orientation applications of graphene, and the theoretical research and practical application of one-dimensional graphene rolls.