Int'l research team confirms ripple structure of graphene

An international research team led by a South Korean professor said Friday that it has confirmed the ripple structure of graphene, a flat layer of carbon atoms that, once fully understood, could significantly enhance the performance of smartphones and other electronic devices. The ripple structure of graphene had long been suspected as application tests yielded much poorer than expected results, especially in terms of electron mobility that supposedly is 100 times higher than those of silicon or copper. The team also confirmed exfoliation, the most widely used method to produce graphene, creates a domain of ripples, making the material anisotropic, which means the domain of ripples in different directions causes different test results when measured along different axes. "Graphene was thought to have high electron mobility as it was believed to have perfectly flat structure. We believe we can now increase its electron mobility to earlier expected levels by flattening its ripples," said Park Bae-ho, professor of quantum phases and devices at Konkuk University who led the science team consisting of 12 other professors and students from six schools and institutions, including the United States' Lawrence Berkeley National Laboratory. Park said the team has also partly confirmed the possibility of flattening ripples of graphene through heat treatment. Once the ripple structure of graphene can be fully controlled, the material can be used to greatly boost the performance and speed of various electronic devices, including semiconductors and transparent electrodes or the touch screens of smartphones, he told Yonhap News Agency. The findings were to be published on the Web site of the international magazine Science later Friday and in its August edition, according to South Korea's Ministry of Education, Science and Technology, which partly funded the project through its World Class University program.