Interview by Zoe Peterkin, AzoNano
What is trickle-down Graphene?
In chemical vapour deposition, we call ‘trickle-down graphene’ as the graphene produced when the carbon radicals catalytically produced on a metal (copper) film trickle down through the metal grain-boundaries to grow graphene directly on the underlying substrate. This process directly grows graphene on most of the relevant substrates.
How does it differ from previous methods used to create Graphene?
Trickle-down graphene is grown directly at the interface between a metal film and its substrate. In other methods, graphene is grown on the open surface of metals, after which it is transferred to a substrate. Our process completely eliminates the transfer process, which generally involves spin-coating of a sticky polymer on graphene, floating graphene/polymer on a solution, picking graphene from the solution on a substrate, washing-off the polymers with nasty solvents, and/or attaching thermal-adhesives on graphene. All these steps are prone to contamination and can lead to tears and wrinkles in graphene. Our process does not need graphene transfer, and therefore is not liable to polymer contamination or structural faults.
What does this new method mean for Graphene production?
In almost all graphene applications, graphene needs to be interfaced with a substrate. This process is a game-changer, since it allows graphene’s direct growth on almost any substrate, thus eliminating a number of fabrication steps involved in production of electronic devices. For example, one can produce a graphene/silicon Schottky solar cell in only two steps without traditional lithography or transfer process.
What new potential applications does Graphene have using this method?
This method enables growth of graphene or its circuits directly on a substrate, which is important for logic devices, multi-junction solar cells, and many other applications.
How will it affect the Graphene industry in the future?
This process is a significant advancement for the ever-growing graphene industry, since it ensures speed of production and consistency between different production batches. Graphene industry has started to think about developing processes that are specific for graphene, while continuing to take inspiration from the existing techniques in the silicon industry. This is a good example of a carbon-specific production mechanism that can further boost the development of the graphene industry.
While a lot of research has gone into making single-grain graphene on metal-surface, further work is needed to minimize the grain-density in trickle-down graphene.
About Dr. Vikas Berry
Dr. Vikas Berry is the Department Head and Associate Professor of Chemical Engineering at University of Illinois at Chicago. Dr. Berry has made pioneering contributions in the fields of graphene quantum materials and Bio/Nano technologies.
As an engineering faculty, Dr. Berry has earned many honors, including the NSF-CAREER Award in 2011; the Sigma Xi Outstanding Junior Scientist Award in 2010; and the Big 12 Fellowship in 2009.
In 2012, Dr. Berry received a professorship appointment (William H. Honstead Professorship) at Kansas State University, which lasted till his move to UIC.
His work on graphene-biointerfaces is considered a nodal point in the evolution of graphene’s biological applications. Dr. Berry is also a member of the editorial board of Scientific Reports and the Journal of Nanoscience Letters.
Research results from Dr. Berry’s group have been published in several high impact journals, including: Nature Communications, Nano Letters, Advanced Materials and Small; and have been featured in Nature, Science News, Washington Post, The Economist, Wall Street Journal, Discover, Chemical Engineering Progress, and Physics World amongst other places.
Berry’s research is funded by the NSF, DoD, and Industry (> $3.5 Million).
Dr. Berry received his bachelor's degree from the Indian Institute of Technology-Delhi, India, in 1999, followed by a master's degree from the University of Kansas in 2003, and a doctorate degree from Virginia Polytechnic Institute and State University in 2006.