We’ve all heard about the wonder material graphene. This allotrope of carbon in hexagonal form on the atomic scale, one-atom-thick, is set to revolutionize the world (at least in theory). Faster CPUs, medical devices, sensors, batteries, ultra-strong materials, unprecedented energy collection…there is seemingly nothing the material can’t be applied for or incorporated into.
And the categories continue to grow. Optoelectronics, spintronics, IR light detection, ethanol distillation, fuel cells, water filtration, and transistors are just a few of the many examples graphene has been used for since its current form inception (single-atom layer) was produced in 2004.
The latest developments utilizing graphene are set to usher in new technology, including supercapacitors designed to bring high-performance and longer-lasting batteries; new transistors for ultra-fast CPUs that will make Moore’s Law obsolete; and graphene-based CMOS image sensors, capable of seeing UV, visible, and infrared light at the same time. Below are some of the more intriguing advancements with graphene that have surfaced this year.
Researchers from the Swinburne University of Technology in Australia have developed a new supercapacitor using a graphene base that could lead to longer-lasting, high-performance batteries. Known as the Bolt Electricity Storage Technology (BEST) battery, it utilizes direct laser printing of thin films of graphene-oxide (a porous version of the wonder material).
The pours are the key to the battery’s high performance, as they provide a larger surface area which holds an increased electrical charge. This new development could sound the death knell for chemical batteries, and it’s the researchers’ aim to pair the new technology with solar cells for greater efficiency in storing and discharging of the collected energy. The team predicts its new battery could be on the market very soon, having filed the patent for BEST last year.
It’s all in the spin. At least, that’s what researchers from the University of Central Florida and several other institutions believe, and with good reason: Their new graphene-based transistors incorporate an all-carbon spin-logic design. These new transistors could bring a new electronic revolution that could lead to CPUs thousands of times faster than anything available today, while requiring very little power to push them.
The researchers developed the new transistors using graphene nanoribbons and carbon nanotubes, and found that by applying a magnetic field to the ribbon, they could change the current resistance flowing through it. By increasing or decreasing that magnetic field, they could adjust the flow of current similar to using a valve to control water through a pipe. Using both the ribbons and nanotubes can create cascading logic gates, which are not physically linked but communicate via an electromagnetic wave. That communication has the potential to run at terahertz speeds and on a much smaller die than what’s found today.
CMOS has transformed the way we use integrated circuits and is in nearly every electronic device in the form of microcontrollers/microprocessors, RAM, and other digital circuitry. Still, it hasn’t changed much since 1976…until now. Scientists from Graphene Flagship (European Research Initiative) have developed new CMOS technology infused with graphene and have successfully incorporated it into an integrated circuit—in this case, a new image sensor capable of seeing the invisible and more.
To develop the new image sensor, the scientists combined the graphene-laced CMOS circuit with quantum dots to produce an array of photodetectors for a high-resolution image sensor, one that can “see” UV, visible, and infrared light at the same time. The team created the graphene-based CMOS wafer using a layering and patterning approach. The graphene is deposited first and patterned into a pixel shape. Next, a layer of PbS colloidal quantum dots is added. These are based on a photogating effect, as the dots absorb light and transfer it as photogenerated electrons to the graphene. The scientists state that there are more applications for the new technology beyond imaging sensors, including fire control, automotive systems, and environmental monitoring.
These examples are just a handful of the developments researchers have designed around graphene with still others pushing the boundaries in molecular electronics, incorporating into fuel cells, and even doping paint for efficient heating and cooling. It’s clear to see that graphene is the go-to material for development in 2017. It will be interesting to see what new and exciting advancements it brings in the years to come.