As a follow-up to the entry I published yesterday, here is another short clip from Rice University (Houston, Texas) in which Messrs Tour and Chyan explain how graphene can be used to tag (i.e. track) different materials. The clip (entitled ‘Graphene on toast, clothing and cardboard has tasty potential’) was uploaded on YouTube on 13 February 2018. 

‘Graphene on toast, clothing and cardboard has tasty potential’

 [Click on the picture with the right button of your mouse, then on ‘picture-in-picture’ in the menu and finally place your cursor on the picture at the bottom of the screen to display the ‘Play’ icon [i.e. the white arrow pointing towards the right] to start the clip, which will thus play in ‘picture-in-picture’ mode.

Source

The following caption appears at the start of the clip: ‘Rice University scientists create patterned graphene onto food, paper, cloth and cardboard.’


James Tour, Chemist, Rice University
We’ve been able to make graphene on many different substrates. Previously we could only make graphene on materials that … that were like polyimide – a particular type of polymer – but now what we’ve found is by tuning the laser a little bit differently and de-focusing the laser, which first carbonises the material and then we take the carbonised material and convert it into graphene. So what you see here is you don’t see ink. This is not ink, this is not the addition of ink to a material; this is taking the material itself – the wood itself – and converting it into graphene. And the laser allows us to write it into any pattern that we wish. This is on a piece of wood or we can do it even on foods – like this is a potato. So we need to remember what graphene is: it’s these single atomic thick sheets of graphite and now we take these and we put a few of them on top of each other, as we convert the material itself – a piece of bread. And so you can convert the carbohydrates that are within bread to graphene. Or we can do it on a coconut; so you can take a coconut and convert that into graphene. Now why would we want to have something like this? This is all conductive and so it can conduct electricity. So what we can do now is we can make electronics embedded within fabrics and make electronics embedded within wood.
 

Yieu Chyan, graduate student, Rice University
So right now, we’re going to be lacing a cardboard box here. And the significance of being able to put electronic traces on cardboard boxes is that it has a lot of potential commercial significance in being able to write RFID tags directly on boxes, so you can either test uh … tell where it’s been or you can put a sensor on the box and see what kind of conditions it’s been exposed to. Currently, people are using RFID tags that have been manufactured and they attach them to the boxes, but being able to directly convert a box would be really valuable.
 
James Tour
Why would one want edible electronics? Well, first of all, let me start with very often we don’t see the advantage of something early on, but, when we make it available, people start seeing the real advantage. So can you even take … have electronics embedded on food and then say ‘use this as a heat circuit to heat the food more easily’? If they’re saying ‘RFID tag written on to this potato, where has it been? How long has it been stored? Where did … where, what? What’s its country of origin and its city of origin, and what path did it go to … to get to your table?’ All that can be embedded, not on a separate tag that’s placed on the food, but directly on the food itself. And these can also have sensors. Sensors that would detect ecoli. Sensors that would to detect microorganisms that you might not want; they could immediately light up and give you a signal that you don’t want to eat this. So being able to barcode food in a sense could have real advantages.


Links
Graphene on toast, clothing and cardboard has tasty potential
13 Feb 2018
Rice University
https://youtu.be/oaaHLu77pQc

Graphene on toast, anyone?
https://news2.rice.edu/2018/02/13/graphene-on-toast-anyone
 
Rice University scientists create patterned graphene onto food, paper and carboard.
https://magazine.rice.edu/2018/05/graphene-on-toast


Lausanne, the lines above were posted on the twenty-eighth day of the sixth month of the year two thousand and twenty-two.