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Some recent breakthroughs that solidify the position of carbon as a material of choice in electronics & structural applications

 


#ageofcarbon 


In a major breakthrough all carbon based electronics were printed using a 2d aerosol printer. Carbon nanotube as channel,graphene as electrodes and nanocellulose as dielectric. All of these materials were formulated into an ink before printing. Fully recyclable. 



https://pratt.duke.edu/about/news/recyclable-printed-electronics 



A flexible 32 bit microprocessor has already been  printed on a plastic sheet using indium’’gallium’ zinc oxide technology. While this is the most feature complete implementation at present, carbon nanotube / graphene based devices are expected to become more prominent in flexible/2d printed electronics. Especially as they simplify the material requirements. 


https://www.nature.com/articles/s41586-021-03625-w


In another development researchers created OLED by pyrolysis of human hair to create emissive carbon quantum dots. Blue light was emitted from the device. 


https://www.ledinside.com/news/2020/6/humanhair_oleddisplay


One of the main problems with graphene in its use as a semiconductor device is its 0 band gap. Which makes it more of a semimetal  rather than a semiconductor. For it to be useful in a semiconductor device a band gap is necessary.  Hydrogen doping in graphene changes its band gap to 3.5 ev which is wide enough for high voltage optoelectronic applications. 


https://www.nature.com/articles/ncomms13261

Due to its excellent electrical conductivity graphene has immediate applicability as an electrode / ohmic contact material. Because its transparent it can also be used to replace inflexible indium tin oxide as electrode in light emitting diodes. This paper characterizes graphene electrodes, describes some of its applications and compares it with other materials that are currently in use. 

https://www.researchgate.net/publication/230978369

Nitrogen doped graphene was created by researchers from IIT by one step pyrolysis of silk at 400 C. The curious fact is pyrolysis at higher temperatures drives out nitrogen and changes the optoelectronic properties of the material obtained. 



https://www.sciencedirect.com/science/article/abs/pii/S0013468615002960



Carbon nanotubes (cnt) have a wide range of applications as fundamental building blocks in organic electronics,filler materials, sensors etc A key limiting factor has been its economical synthesis. This paper reviews various synthesis techniques for carbon nanotubes and illustrates a new technique of making them from a common household material :camphor

 

https://www.sciencedirect.com/science/article/abs/pii/S0008622307001923



 In yet another advancement, electrostatic nanocapacitors were made from carbon based materials.  


https://pubs.acs.org/doi/10.1021/acsnano.8b05490


https://www.technologyreview.com/2009/03/16/31989/nanocapacitors-with-big-energy-storage/



 Scientists managed to hydrolyze cellulose,lignin and hemicellulose to bio oil using a cheap recyclable feedstock -- citric acid in a completely green synthesis. Trillions of tons of cellulose is produced per year on earth. If an effective recycling technique of citric acid can be developed then energy is a solved problem.This technique will prove to be especially useful in sustainable aviation fuels 


https://pubs.rsc.org/en/content/articlelanding/2020/ra/d0ra06542k#


Nano engineered cellulose that has proven stronger than kevlar,stronger than steel,stronger than spider silk is the newest carbon based material that can replace petroleum based plastics. And the best part is it grows on trees 


https://paper360.tappi.org/2019/01/08/threads-of-nanocellulose-stronger-than-spider-silk/


This is just a short summary of recent developments in carbon materials technology. Nearly everyday new methods of synthesizing carbon based materials are being discovered. These are exciting times for Carbon scientists and engineers. Carbon offers unlimited flexibility for a material engineer. It's unsurprising that it's hailed as a material of the future. 


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