Graphene antenna

A graphene antenna printed on to a piece of paper could offer those with demanding logistics require a more discrete and flexible alternative to current RFID (radio frequency identification) tagging system for products, equipment and other entities.

The new graphene antenna has been devised by researchers at The University of Manchester, UK, and because it avoid the use of metals, aluminum and copper. it is cheaper and more sustainable overall than current approaches to these ubiquitous inventory and security tags. The same technology might also find utility in wireless sensors and other related areas. Currently, metal nanoparticles, conductive polymers and carbon nanomaterials are the focus of research aimed at developing conductive inks, but graphene may well offer advantages over these materials: metals are expensive and become oxidized, for instance, whereas polymers are prone to thermal instability.

The team's development of a compressed graphene ink - a highly conductive graphene laminate that avoids the use of insulating binder substance - offers a way to increase dramatically the conductivity of RFID tags as well as being printable on materials such as paper and textiles. The low-temperature (100 degrees Celsius) compression process boosts the conductivity of the graphene by more than fifty times, the team says. The graphene laminate has a conductivity of 4.3 ×10^4 Siemens per meter. It is composed of highly densified graphene nanoflakes, dispersants, and solvents, but no binders. Zhirun Hu and colleagues discuss the printing of a graphene antenna on to a piece of paper in the journal Applied Physics Letters [2015; DOI: 10.1063/1.4919935]. Tests demonstrate that the antenna radiates radio frequency energy effectively.

Printable electronics have come to the experimental fore in recent years with the quest to find conductive materials that can be dispensed in fluid form under computer control using an inkjet printer for instance or used in industrial scale lithographic, screen, printing. The potential for being able to print flexible display, develop inexpensive biomedical and chemical sensors with particularly utility in the developing world for instance, RFID technology, wearable electronics, energy harvesting and storage systems and much more is staggering.

"We started to work on these antennae only recently, but even our first results prove that this technology is already better than the ones currently used," Hu says. The researchers at the National Graphene Institute at The University of Manchester team have a wider research program in which printable graphene electronics and devices is just the first step, with intensive work on other two-dimensional materials underway.

David Bradley blogs at Sciencebase Science Blog and tweets @sciencebase, he is author of the bestselling science book "Deceived Wisdom".