Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Transparent graphene electrodes might lead to new generation of solar cells: New roll-to-roll production method could enable lightweight, flexible solar devices and a new generation of display screens

A new manufacturing process for graphene is based on using an intermediate carrier layer of material after the graphene is laid down through a vapor deposition process. The carrier allows the ultrathin graphene sheet, less than a nanometer (billionth of a meter) thick, to be easily lifted off from a substrate, allowing for rapid roll-to-roll manufacturing. These figures show this process for making graphene sheets, along with a photo of the proof-of-concept device used (b).

Courtesy of the researchers
A new manufacturing process for graphene is based on using an intermediate carrier layer of material after the graphene is laid down through a vapor deposition process. The carrier allows the ultrathin graphene sheet, less than a nanometer (billionth of a meter) thick, to be easily lifted off from a substrate, allowing for rapid roll-to-roll manufacturing. These figures show this process for making graphene sheets, along with a photo of the proof-of-concept device used (b). Courtesy of the researchers

Abstract:
A new way of making large sheets of high-quality, atomically thin graphene could lead to ultra-lightweight, flexible solar cells, and to new classes of light-emitting devices and other thin-film electronics.

Transparent graphene electrodes might lead to new generation of solar cells: New roll-to-roll production method could enable lightweight, flexible solar devices and a new generation of display screens

Cambridge, MA | Posted on June 8th, 2020

The new manufacturing process, which was developed at MIT and should be relatively easy to scale up for industrial production, involves an intermediate “buffer” layer of material that is key to the technique’s success. The buffer allows the ultrathin graphene sheet, less than a nanometer (billionth of a meter) thick, to be easily lifted off from its substrate, allowing for rapid roll-to-roll manufacturing.

The process is detailed in a paper published yesterday in Advanced Functional Materials, by MIT postdocs Giovanni Azzellino and Mahdi Tavakoli; professors Jing Kong, Tomas Palacios, and Markus Buehler; and five others at MIT.

Finding a way to make thin, large-area, transparent electrodes that are stable in open air has been a major quest in thin-film electronics in recent years, for a variety of applications in optoelectronic devices — things that either emit light, like computer and smartphone screens, or harvest it, like solar cells. Today’s standard for such applications is indium tin oxide (ITO), a material based on rare and expensive chemical elements.

Many research groups have worked on finding a replacement for ITO, focusing on both organic and inorganic candidate materials. Graphene, a form of pure carbon whose atoms are arranged in a flat hexagonal array, has extremely good electrical and mechanical properties, yet it is vanishingly thin, physically flexible, and made from an abundant, inexpensive material. Furthermore, it can be easily grown in the form of large sheets by chemical vapor deposition (CVD), using copper as a seed layer, as Kong’s group has demonstrated. However, for device applications, the trickiest part has been finding ways to release the CVD-grown graphene from its native copper substrate.
This release, known as graphene transfer process, tends to result in a web of tears, wrinkles, and defects in the sheets, which disrupts the film continuity and therefore drastically reduces their electrical conductivity. But with the new technology, Azzellino says, “now we are able to reliably manufacture large-area graphene sheets, transfer them onto whatever substrate we want, and the way we transfer them does not affect the electrical and mechanical properties of the pristine graphene.”
The key is the buffer layer, made of a polymer material called parylene, that conforms at the atomic level to the graphene sheets on which it is deployed. Like graphene, parylene is produced by CVD, which simplifies the manufacturing process and scalability.

As a demonstration of this technology, the team made proof-of-concept solar cells, adopting a thin-film polymeric solar cell material, along with the newly formed graphene layer for one of the cell’s two electrodes, and a parylene layer that also serves as a device substrate. They measured an optical transmittance close to 90 percent for the graphene film under visible light.

The prototyped graphene-based solar cell improves by roughly 36 times the delivered power per weight, compared to ITO-based state-of-the-art devices. It also uses 1/200 the amount of material per unit area for the transparent electrode. And, there is a further fundamental advantage compared to ITO: “Graphene comes for almost free,” Azzellino says.

“Ultra-lightweight graphene-based devices can pave the way to a new generation of applications,” he says. “So if you think about portable devices, the power per weight becomes a very important figure of merit. What if we could deploy a transparent solar cell on your tablet that is able to power up the tablet itself?” Though some further development would be needed, such applications should ultimately be feasible with this new method, he says.

The buffer material, parylene, is widely used in the microelectronics industry, usually to encapsulate and protect electronic devices. So the supply chains and equipment for using the material already are widespread, Azzellino says. Of the three existing types of parylene, the team’s tests showed that one of them, which contains more chlorine atoms, was by far the most effective for this application.

The atomic proximity of chlorine-rich parylene to the underlying graphene as the layers are sandwiched together provides a further advantage, by offering a kind of “doping” for graphene, finally providing a more reliable and nondestructive approach for conductivity improvement of large-area graphene, unlike many others that have been tested and reported so far.

“The graphene and the parylene films are always face-to-face,” Azzellino says. “So basically, the doping action is always there, and therefore the advantage is permanent.”

The research team also included Marek Hempel, Ang-Yu Lu, Francisco Martin-Martinez, Jiayuan Zhao and Jingjie Yeo, all at MIT. The work was supported by Eni SpA through the MIT Energy Initiative, the U.S. Army Research Office through the Institute for Soldier Nanotechnologies, and the Office of Naval Research.

####

For more information, please click here

Contacts:
Abby Abazorius

Phone: 617-253-2709
MIT News Office

Copyright © Massachusetts Institute of Technology

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

2 Dimensional Materials

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Understanding electron transport in graphene nanoribbons: New understanding of the electrical properties of graphene nanoribbons (GRBs), when bounded with aromatic molecules, could have significant benefits in the development of chemosensors and personalized medicine September 11th, 2020

Ambient light alters refraction in 2D material: Rice researchers find effect that could aid 3D displays, virtual reality, self-driving vehicles September 2nd, 2020

News and information

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Display technology/LEDs/SS Lighting/OLEDs

Shedding Light on the Development of Efficient Blue-Emitting Semiconductors September 18th, 2020

Ambient light alters refraction in 2D material: Rice researchers find effect that could aid 3D displays, virtual reality, self-driving vehicles September 2nd, 2020

A light bright and tiny: NIST scientists build a better nanoscale LED: New design overcomes long-standing LED efficiency problem -- and can transform into a laser to boot August 14th, 2020

Graphene/ Graphite

Understanding electron transport in graphene nanoribbons: New understanding of the electrical properties of graphene nanoribbons (GRBs), when bounded with aromatic molecules, could have significant benefits in the development of chemosensors and personalized medicine September 11th, 2020

Nano-diamond self-charging batteries could disrupt energy as we know it August 25th, 2020

Rescue operations become faster thanks to graphene nanotubes August 20th, 2020

Thin films

FEFU scientists are paving way for future tiny electronics and gadgets August 28th, 2020

Govt.-Legislation/Regulation/Funding/Policy

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Fast calculation dials in better batteries: Analytical model from Rice University helps researchers fine-tune battery performance September 16th, 2020

Possible Futures

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Discoveries

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Materials/Metamaterials

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Get diamonds, take temperature: Quantum thermometer using nanodiamonds senses a 'fever' in tiny worms C. elegans September 11th, 2020

Quantitatively understanding of angle-resolved polarized Raman scattering from black phosphorus September 11th, 2020

Announcements

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

Who stole the light? Self-induced ultrafast demagnetization limits the amount of light diffracted from magnetic samples at soft x-ray energies September 18th, 2020

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Military

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Boundaries no barrier for thermoelectricity: Rice researchers find potentially useful electrical phenomenon in gold nanowires September 8th, 2020

No limit yet for carbon nanotube fibers: Rice lab makes case for high-performance carbon nanotube fibers for industry August 17th, 2020

A light bright and tiny: NIST scientists build a better nanoscale LED: New design overcomes long-standing LED efficiency problem -- and can transform into a laser to boot August 14th, 2020

Energy

Shedding Light on the Development of Efficient Blue-Emitting Semiconductors September 18th, 2020

An improved wearable, stretchable gas sensor using nanocomposites August 28th, 2020

UCF researchers generate attosecond light from industrial laser: The ultrafast measurement of the motion of electrons inside atoms, molecules and solids at their natural time scale is known as attosecond science and could have important implications in power generation, chemical- August 25th, 2020

Synthesis of organophilic carbon nanodots with multi-band emission from tomato leaves August 21st, 2020

Photonics/Optics/Lasers

Who stole the light? Self-induced ultrafast demagnetization limits the amount of light diffracted from magnetic samples at soft x-ray energies September 18th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

A phonon laser - coherent vibrations from a self-breathing resonator September 11th, 2020

Quantitatively understanding of angle-resolved polarized Raman scattering from black phosphorus September 11th, 2020

Solar/Photovoltaic

Layer of nanoparticles could improve LED performance and lifetime August 7th, 2020

May the force be with you: Detecting ultrafast light by its force: From cell phones to solar cells - research has implications for improvements in a wide range of technologies August 7th, 2020

Crystal structure discovered almost 200 years ago could hold key to solar cell revolution July 3rd, 2020

Printed perovskite LEDs: An innovative technique towards a new standard process of electronics manufacturing June 12th, 2020

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project