Graphene is a substance which exhibits strong conduction, flexibility, and strength all at the same time. One area that may see the widespread use of graphene is in transparent, flexible displays. However, there are other areas that graphene could be utilized. These areas include wearable electronics, medical applications, and even quantum computing.
If graphene is to be used in applications which involve exposure to humans, a non-toxic process is one that will be the most ideal. Creating a non-toxic process is exactly what a team at the Cambridge Graphene Centre have done.
A Growing Concern
Governments around the world have made efforts to encourage more responsible electronics production and disposal.
Once they're thrown away, old electronic parts don't just disappear. Image courtesy of Curtis Palmer [CC by 2.0]
These efforts have varying degrees of effectiveness, but some legislation has shown positive change. One example of effective change is the European Union's effort to remove harmful substances such as lead, mercury, and cadmium from consumer products. Unfortunately, some processes are reliant on toxic chemistry to function correctly with little or no alternative.
For example, the PCB fabrication industry relies on particularly environmentally unfriendly chemicals such as copper sulfate which is needed during the electroplating process. Other dangerous chemicals include formaldehyde, thiourea, and many acids. Banning the use of such chemicals would be an industrial, commercial, and financial nightmare which is why there are strict laws on how we should dispose of these substances.
If a manufacturing process can avoid harmful chemicals, not only does the manufacturer benefit (reduced health risk to workers), but so does the end user (reduction of exposure), and the environment.
A Non-Toxic Production Method
Working in collaboration with Jiangnan University, China, the Cambridge Graphene Centre has developed a non-toxic method for depositing graphene ink onto clothing.
One of the most widespread materials used for clothing is cotton because of its breathability, weight, and availability. Because of this, the team had to develop a graphene ink that would essentially stick better to the cotton fibers in a similar fashion to color dyes as to prevent destruction during wear and tear.
Once the ink had been applied to the cotton the material was heat treated to further improve the conductivity of the graphene ink. Even after several washes, the ink remained conductive, which is imperative for electronics impregnated into materials.
The graphene ink on cotton. Photo by Jiesheng Ren [CC BY 4.0]
Currently, wearable sensors aren't widely commercially available, largely because of rigid designs that either will not wear well or wash well, making the clothing uncomfortable. The Cambridge team demonstrated the capability of the graphene ink in their published work by creating a motion sensor based on the conductive material which gave successful results. The motion sensor had been shown to work past 500 cycles after 10 washes—a big leap in the field of wearable, non-toxic graphene.
"Turning cotton fibers into functional electronic components can open to an entirely new set of applications from healthcare and wellbeing to the Internet of Things. Thanks to nanotechnology, in the future our clothes could incorporate these textile-based electronics and become interactive." - Dr Torrisi
Scanning electron microscope image of the ink on cotton Photo by Jiesheng Ren [CC BY 4.0]
The Future of Wearable Electronics
Nearly every aspect of life has been invaded by electronics to some degree. Cars now have sensors and cameras, houses are beginning to have intelligent heating controls, and even internet-ready toasters exist. In fact, there are very few areas of life that electronics are yet to become involved with so the appeal of clothing becoming more integrated with electronics is one that comes as no surprise.
However, unlike the other sectors that electronics have found their way into, the use of harmful substances cannot be tolerated considering how many people suffer from skin conditions and how many clothes find themselves in landfills.
If electronics are to be integrated into clothing, then it's up to designers to utilize the materials that will lead to a safe end product.