Researchers from Purdue University, the University of Michigan and the Huazhong University of Science and Technology have used a technique called "laser shock imprinting" to permanently stress graphene into having a band gap, which could mean it would be possible to use it in various electronic components.
The researchers used a laser to create shock wave impulses that penetrated an underlying sheet of graphene. The laser shock stretches the graphene onto a permanent, trench-like mold. This caused the widening of band gap in graphene to a record 2.1 electronvolts. Previously, scientists achieved 0.5 electronvolts, barely reaching the benchmark to make graphene a semiconductor like silicon.
"This is the first time that an effort has achieved such high band gaps without affecting graphene itself, such as through chemical doping," said the paper's corresponding author Gary Cheng, professor of industrial engineering at Purdue University.
The team not only kept the band gap open in graphene, but also made it to where the gap width could be tuned from zero to 2.1 electronvolts, giving scientists and manufacturers the option to just use certain properties of graphene depending on what they want the material to do. There is still a way to go before turning graphene into a semiconducting device, but the technique provided more possibilities in taking advantage of the material's optical, magnetic and thermal properties, according to the team.
