Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Northwestern researchers achieve unprecedented control of polymer grids: Materials could find applications in water purification, solar energy storage, body armor

Covalent organic frameworks (COFs) offer a unique combination of properties that show promise for waterpurification, energy storage and electronic devices.
Covalent organic frameworks (COFs) offer a unique combination of properties that show promise for waterpurification, energy storage and electronic devices.

Abstract:
Materials are called two-dimensional covalent organic frameworks
These materials fill a long-standing gap in polymer science
Precision of structure, plentiful pores give scientists design control
Hexagonal pores provide extremely high surface area

Northwestern researchers achieve unprecedented control of polymer grids: Materials could find applications in water purification, solar energy storage, body armor

Evanston, IL | Posted on June 22nd, 2018

Synthetic polymers are ubiquitous -- nylon, polyester, Teflon and epoxy, to name just a few -- and these polymers are all long, linear structures that tangle into imprecise structures. Chemists have long dreamed of making polymers with two-dimensional, grid-like structures, but this goal has proven challenging.

The first examples of such structures, now known as covalent organic frameworks (COFs), were discovered in 2005, but their quality has been poor and preparation methods are uncontrolled. Now a Northwestern University research team is the first to produce high-quality versions of these materials, demonstrate their superior properties and control their growth.

The researchers developed a two-step growth process that produces organic polymers with crystalline, two-dimensional structures. The precision of the material’s structure and the empty space its hexagonal pores provide will allow scientists to design new materials with desirable properties.

Even low-quality COFs have shown preliminary promise for water purification, storing electricity, body armor and other tough composite materials. Once developed further, higher-quality samples of these materials will enable these applications to be explored more fully.

“These covalent-organic frameworks fill a century-long gap in polymer science,” said William Dichtel, an expert in organic and polymer chemistry who led the study. “Most plastics are long, linear structures that tangle up like spaghetti. We have made ordered two-dimensional polymers where the building blocks are arranged in a perfect grid of repeating hexagons. This gives us precise control of the structure and its properties.”

Dichtel is the Robert L. Letsinger Professor of Chemistry at Northwestern’s Weinberg College of Arts and Sciences.

The study, “Seeded Growth of Single-Crystal Two-Dimensional Covalent Organic Frameworks,” will be published on June 21 by the journal Science via First Release. (The paper will appear in print at a later date.)

The 2D COFs have permanent pores and extremely high surface area. Imagine the surface area of a football field contained in about two grams of material, or two paper clips, Dichtel said. Every little hole is the same size and shape and has exactly the same composition.

In the two-step process, the scientists first grow small particle “seeds” to which they slowly add more of the building blocks, under carefully controlled conditions. The slow addition causes the building blocks to add to the seeds instead of creating new seeds. The result is larger, high-quality particles made up of large, hexagonal sheets instead of a bunch of aggregated crystals.

“This is primarily a synthesis paper, but we also measured properties that emerge only in these high-quality samples,” Dichtel said. “For example, we show that energy can move throughout the structure after it absorbs light, which may be useful in solar energy conversion.”

Once the 2D COFs were grown, fellow chemists Nathan C. Gianneschi and Lucas R. Parent carefully studied the particles using an electron microscope. They confirmed the particles are individual and not aggregated and are perfectly uniform throughout the entire structure.

Gianneschi is the Jacob and Rosaline Cohn Professor in the department of chemistry in Weinberg College. He also is a professor in the departments of materials science and engineering and of biomedical engineering in the McCormick School of Engineering. Parent is a postdoctoral fellow in Gianneschi’s group. Both are co-authors of the paper.

Next, Lin X. Chen and Richard D. Schaller measured how one of the materials interacts with light. Their studies show that energy can move through these materials for much longer distances than the sizes available through old methods.

Chen is a professor of chemistry, and Schaller is an assistant professor of chemistry, both in Weinberg. Both are co-authors of the paper.

“This study has been very gratifying -- to successfully grow these materials and begin to see their promise,” Dichtel, who has been studying COFs for a decade. “We think this development will be enabling for the field of polymer science.”

An Army Research Office for a Multidisciplinary University Research Initiatives (MURI) award (grant number W911NF-15-1-0447) supported this research.

####

For more information, please click here

Contacts:
Source contact:
William Dichtel


MEDIA CONTACT:
Megan Fellman
847-491-3115

Copyright © Northwestern University

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

News and information

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

Chirality in 'real-time' January 14th, 2019

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Media invited to open meeting on the future of quantum technology held at RIT Jan. 23-25: Leaders from NASA, NSF, NIST and Sandia National Laboratory to attend January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

2 Dimensional Materials

2D materials may enable electric vehicles to get 500 miles on a single charge January 11th, 2019

2-D magnetism: Atom-thick platforms for energy, information and computing research: Scientists say the tiny 'spins' of electrons show potential to one day support next-generation innovations in many fields October 31st, 2018

Rice U. scientists form flat tellurium: Two-dimensional element shows promise for solar cells and other optoelectronics October 26th, 2018

Law enforcement/Anti-Counterfeiting/Security/Loss prevention

A bullet-proof heating pad November 2nd, 2018

Biomimetic micro/nanoscale fiber reinforced composites August 10th, 2018

Possible Futures

Chirality in 'real-time' January 14th, 2019

Media invited to open meeting on the future of quantum technology held at RIT Jan. 23-25: Leaders from NASA, NSF, NIST and Sandia National Laboratory to attend January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

Materials/Metamaterials

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

2D materials may enable electric vehicles to get 500 miles on a single charge January 11th, 2019

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Announcements

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

Chirality in 'real-time' January 14th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

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

2D materials may enable electric vehicles to get 500 miles on a single charge January 11th, 2019

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

Homeland Security

A bullet-proof heating pad November 2nd, 2018

Powering the 21st Century with Integrated Photonics: UCSB-Led Team Selected for Demonstration of a Novel Waveguide Platform Which is Transparent Throughout the MWIR and LWIR Spectral Bands June 19th, 2018

Squeezing light at the nanoscale: Ultra-confined light could detect harmful molecules June 17th, 2018

The dispute about the origins of terahertz photoresponse in graphene results in a draw April 26th, 2018

Military

Cartilage could be key to safe 'structural batteries' January 11th, 2019

DNA design that anyone can do: Computer program can translate a free-form 2-D drawing into a DNA structure January 4th, 2019

E-bandage generates electricity, speeds wound healing in rats December 28th, 2018

Bending light around tight corners without backscattering losses: New photonic crystal waveguide based on topological insulators paves the way to build futuristic light-based computers November 19th, 2018

Energy

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Physicists uncover new competing state of matter in superconducting material January 4th, 2019

Revealing hidden spin: Unlocking new paths toward high-temperature superconductors: Berkeley Lab researchers uncover insights into superconductivity, leading potentially to more efficient power transmission January 4th, 2019

Water

Study unlocks full potential of 'supermaterial' graphene: Researchers remove silicon contamination from graphene to double its performance November 30th, 2018

Aculon, Inc. Enters into Strategic Partnership Agreement with Henkel Corporation to Supply Key Mobile Device Manufacturers with NanoProof® PCB Waterproof Technology October 17th, 2018

Silver nanoparticles are toxic for aquatic organisms: A research team at the UPV/EHU-University of the Basque Country has analysed how zebrafish are affected in the long term by exposure to silver particles September 19th, 2018

Halas wins American Chemical Society Award in Colloid Chemistry: Rice University nanophotonics pioneer honored for colloid research September 18th, 2018

Battery Technology/Capacitors/Generators/Piezoelectrics/Thermoelectrics/Energy storage

2D materials may enable electric vehicles to get 500 miles on a single charge January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

Disordered crystals are promising for future battery technology December 21st, 2018

Rice U. scientists form flat tellurium: Two-dimensional element shows promise for solar cells and other optoelectronics October 26th, 2018

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Scientists program proteins to pair exactly: Technique paves the way for the creation of protein nanomachines and for the engineering of new cell functions December 21st, 2018

Strem Chemicals, Inc., Receives National Performance Improvement Honor: Company Recognized for Stakeholder Communications December 20th, 2018

Superfluidity: what is it and why does it matter? December 20th, 2018

Arrowhead Pharmaceuticals Reports Inducement Grants under NASDAQ Marketplace Rule 5635(c)(4) December 18th, 2018

Solar/Photovoltaic

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Study unlocks full potential of 'supermaterial' graphene: Researchers remove silicon contamination from graphene to double its performance November 30th, 2018

Perovskite solar cells leap toward commercialization September 28th, 2018

September 5th, 2018

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