Diabetes treatment and high-energy-density batteries: latest developments in graphene It seems like every week, there is a new innovation making use of graphene’s amazing properties to solve more problems. The most recent of these is a graphene–based patch to treat diabetes, reported in Nature Nanotechnology. This flexible skin patch, developed by researchers at Seoul National University, Republic of Korea and U.S. electronics firm MC10, can detect blood glucose levels, and deliver drugs if needed. The patch uses tiny sweat sensors to monitor glucose levels.
If high levels are detected, this triggers micro-needles to deliver the drug Metformin. This has already been used successfully to keep blood sugar levels under control mice with Type II diabetes. This is the first prototype to combine the monitoring of blood glucose levels with administering treatment.
Also in Nature Nanotechnology, layered reduced graphene oxide has been demonstrated as a stable host for lithium metal anodes. While metallic lithium is a promising anode candidate for future high-energy-density batteries, a challenge is presented by its almost infinite relative dimension change during cycling. To overcome this, a composite lithium metal anode has been developed, composed of 7 wt% ‘lithiophilic’ layered reduced graphene oxide with nanoscale gaps that can host metallic lithium. The anode retains up to ∼3,390 mAh g–1 of capacity, exhibits low overpotential and a flat voltage profile in a carbonate electrolyte.
A full-cell battery with a LiCoO2 cathode shows good rate capability and flat voltage profiles. These are just two of the countless developments in graphene technology, ranging from medical advancements to high-energy batteries. The unique properties of graphene – high carrier mobility, conductivity, flexibility and optical transparency, to mention just a few – promise many more exciting discoveries and technologies in the future.
