Partial breaking of the Coulombic ordering of ionic liquids confined in carbon nanopores

Just Squeeze In — Drexel Researchers Discover When Spaces Are Tight, Nature Loosens Its Laws

It turns out that when they’re in a hurry and space is limited, ions, like people, will find a way to cram in — even if that means defying nature’s norms. Recently published research from an international team of scientists, including Drexel University’s Yury Gogotsi, PhD, shows that the charged particles will actually forgo their “opposites attract” behavior, called Coulombic ordering, when confined in the tiny pores of a nanomaterial. This discovery could be a pivotal development for energy storage, water treatment and alternative energy production technologies, which all involve ions packing into nanoporous materials.An international team of researchers, including Drexel's Yury Gogotsi, PhD, observed that ions will forgo their typical alternating charge ordering when they are forced to jam into a small, sub-nanometer-sized, space — a behavior modification not unlike people relinquishing personal space in order to pack into a crowded subway car. The discovery could lead to safer energy storage devices and better water filtration membranes.

In their paper, which was recently published in the journal Nature Materials, the researchers explain how Coulombic ordering in liquid salts starts to break down when ions are confined in small spaces — specifically carbon pores less than a nanometer in diameter. And the narrower the pore, the less the ions adhere to Coulombic ordering.

“This is the first time breaking of the Coulombic ordering in subnanometer pores has been convincingly demonstrated,” said Gogotsi, an author of the paper, who is the Distinguished University and Bach professor in Drexel’s College of Engineering. “The breaking of symmetry principals, like Coulombic ordering, plays an essential role in nature. But many of these processes occur without us understanding them and knowing their mechanisms. Science can reveal those hidden processes. And if we understand them, we can eventually develop better technology by working at the same nanometer and subnanometer scales that nature does.”

To make its discovery, the team — including researchers from Shinshu University in Japan; Loughborough University in the United Kingdom; The University of Adelaide in Australia; and Sorbonne University, the French Research Network on Electrochemical Energy Storage, and Paul Sabatier University in France — created two sets of carbon nanomaterials. One had pores at least a nanometer in diameter and one with pores less than a nanometer. They then used the materials to draw in ionic liquid as if they were a sponge sopping up water.

In ionic liquids, which are room-temperature liquid salts often used as solvents in the chemical industry, ions are layered in full compliance with the alternating positive-negative pattern of Coulombic ordering. But as the ionic liquid drew into the carbon nanopores it forced the ions to line up in single- and double-file lines. And, like a flock of elementary schoolers running for the bus, they didn’t always end up in line next to their usual cohorts.

“In this state, the Coulombic ordering of the liquid is broken,” the authors wrote. “Ions of the same charge neighbor each other due to a screening of their electrostatic interactions by the image charges induced in the pore walls.”

When packed into pore channels as narrow as a nanometer or less, ions will forgo their typical positive-negative alternating charge ordering. They will form a single (right) or double-file (left) line, many times queuing up next to ions of the same charge.

The team observed this disruption in the natural order of ions through x-ray scattering and modeled the process to explain the experimental observations. They also reported that the non-Coulombic ordering became more pronounced when an electric charge was applied to the carbon material.

“Our results suggest the existence of a molecular-scale mechanism that reduces the Coulombic repulsion energy between co-ions that become closer to each other,” they wrote. This mechanism, they theorize, is linked to the charge temporarily imposed on the walls of the carbon pores. This “image charge,” they write, offsets the natural electrostatic repulsion of ions of the same charge, to allow the channels to fill with same-charged ions lined up next to each other.

Gogotsi suggests this discovery could make it more feasible to use ionic liquids in batteries and other energy storage devices, which has been examined as a method for making batteries safer but has yet to catch on because it limits their performance.

“We can get safer batteries and supercapacitors when using ionic liquid electrolytes because they are not flammable like the electrolyte solution currently used in these devices,” Gogotsi said. “Also, since there is no solvent, the entire volume is occupied by ions and we may be able to store more energy compared to conventional electrolytes that use organic solvents.”

He’s also looking at this discovery as one that could have a significant impact on the push for water desalination technology. Membranes currently being developed to turn salt water into drinking water could be improved with this knowledge about ion behavior within subnanometer pores.

“This work adds fundamental understanding to how different things can behave below one nanometer in scale,” Gogotsi said. “We go beyond nanotechnology and into sub-nanoscale process — that’s the next frontier.”

Source: http://drexel.edu/now/archive/2017/September/nanopore-non-Coulombic-ordering/

 

 

 

 

News from MRC.ORG.UA

ADVANCED SCIENCE NEWS: Yury Gogotsi was a chemist from the very beginning. He feels the excitement of scientific discovery, and cannot imagine doing anything else

Professor Yury Gogotsi, Drexel University, Philadelphia, USA

Yury Gogotsi was a chemist from the very beginning. He feels the excitement of scientific discovery, and cannot imagine doing anything else. It was love at first sight for Yury Gogotsi. 

Gogotsi feels that the greatest recent step in the field of materials science was the discovery of new 2D materials, the “building blocks of the future”. He is very enthusiastic about the use of nanotechnology to generate “new artificial materials, structures and devices from nanoscale building blocks” and the increased application of “modeling, simulation, and machine learning for solving materials science problems”, though he admits concern regarding the unknown effects that artificial intelligence will have on our future lives. He is also conscious of the energy required for computation and the importance of exploiting renewable resources to develop new technologies – ones that reduce energy consumption. “We need revolutionary discoveries here,” he says. “Evolutionary development won’t be enough.”

 
Horizon 2020 NANO2DAY project participants from the Materials Research Center (MRC), Kiev, Ukraine, Alexey Gogotsi and Veronika Zahorodna visited the partner organization Drexel University, Philadelphia, USA, on September-October 2018

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NANO2DAY project participants from the Materials Research Center (MRC), Kiev, Ukraine, Alexey Gogotsi (MRC project leader) and Veronika Zahorodna (early-staged researcher, in the framework of international scientific cooperation on the Horizon 2020 program, visited the partner organization Drexel University, Philadelphia, USA, on September-October 2018 in accordance with the travel plan on the project to perform planned project activities.

 
MRC director Oleksiy Gogotsi at the work meeting in Drexel University, Philadelphia, USA, made a presentation of the company and its activitties in international r&d projects

altDirector of Materials Research Centre (Kiev, Ukraine) Oleksiy Gogotsi  at the work meeting in Drexel University, Philadelphia, USA, made a  presentation of the company and its activitties in international research and development projects. Also Oleksiy Gogotsi presented HORIZON 2020 MSCA RISE Project №777810 NANO2DAY: MULTIFUNCTIONAL POLYMER COMPOSITES DOPED WITH NOVEL 2D NANOPARTICLES FOR ADVANCED APPLICATIONS.

 
Seminar on 2D Materials Beyond Graphene by prof. Zdenek Sofer University of Chemistry and Technology (Prague) at Drexel University, USA, on October 18, 2018

altDuring NANO2DAY project visit  to Drexel University (Philadelphia, USA), director of Materials Research Centre (kiev, Ukraine) Oleksiy Gogotsi met with Assoc. Prof. Zdeněk Sofer from University of Chemistry and Technology, Prague (Chech Republic) and attended his seminar on nanomaterials. Prof. Zdenek Sofer in Drexel University gave an excellent seminar on 2D Materials Beyond Graphene.

 
NANO2DAY project: research scientist Maksym Plakhothyuk, Technical University of Denmark (DTU), visited Ukrainian partner Materials Research Centre, Kiev, Ukraine on September-November 2018

NANO2DAY project Maksym Plakhotnyuk, DTU visited MRC, November 2018Due to the NANO2DAY project under european scientific  research program HORIZON 2020 research scientist  Maksym Plakhothyuk, Technical University of Denmark (DTU), visited Ukrainian partner Materials Research Centre, Kiev, Ukraine on September-November 2018. 

 
Congratulations to Professor Yury Gogotsi who received prestigious Chineese Government Friendship Award, Beijing, Great Hall of the People, September 29, 2018

Yury Gogotsi recevide Friendship Award from Chinas GovernmentChina"s Government Friendship Award ceremony was held in Great Hall of the People, in Beijing on September 29, 2018, the award to the winners were presented by the Vice Premier of China Liu He. The People's Republic of China Government Friendship Award is China's highest award for foreign experts who have made outstanding contributions to the country's economic and social progress.

 
Spray-On Antennas Could Be the Tech Connector of the Future

Invisibly thin MXene antennas can be applied to a variety of substrates and perform better than antenna materials currently used in mobile devices.

Now, researchers at Drexel University have developed a method for creating nearly invisible antennas on almost any surface by literally spraying them on like paint. The antennas are made from a special two-dimensional metallic material called MXene. MXene powder can be dissolved in water to create a paint that is then airbrushed on. In tests, even a layer as thin as just 62 nanometers – thousands of times thinner than a sheet of paper – could communicate effectively. Performance maxed out at just 8 microns, a point at which the spray-on antennas worked just as well as those currently used in mobile devices and wireless routers.

 
Congratulations to professor Yury Gogotsi, professor Rodney S. Ruoff and professor Patrice Simon with being named by Clarivate Analythics among of the 17 most cited and influenced world-class scientists in 2018!

Professor Yury GogotsiThis designation celebrates researchers whose influence is comparable to that of Nobel Prize recipients, as attested by exceptionally high citation records within the Web of Science. 

 
15th YES Annual Meeting: “The Next Generation of Everything” September 13 – 15, 2018

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Yalta European Strategy (YES)  introduced nightcap events for the participants of the 15th YES Annual Meeting to wind down at the end of the first conference day and discuss interesting topics in an informal atmosphere. YES invited leading politicians, opinion makers and business leaders to present their views on modern trends that define the world and Ukraine. The nightcaps were organized in partnership with the U.S. Embassy in Ukraine and America House, International Renaissance Foundation, Ukrainian-Jewish Encounter and the Atlantic Council, Mejlis of the Crimean Tatar people and Ministry of Information Policy of Ukraine, Western NIS Enterprise Fund and Embassy of the Republic of Estonia.

 
2018 IEEE 8th International Conference on Nanomaterials: Applications & Properties, September 09-14, 2018

2018 IEEE International Conference on “Nanomaterials Applications & Properties”At the poster session of the conference Oleksiy Gogotsi presented two poster presentations on advanced nanomaterials for different applications, prepared with colleagues from Drexel University, USA, and Jilin University, China

 
NANO2DAY project participants Oleksiy Gogotsi and Veronika Zahorodna visited Polymer Institute SAS, Bratislava, Slovakia, July-September 2018

altNANO2DAY project participants from Materials Research Centre, Kiev, Ukraine, MRC director and project leader Oleksiy Gogotsi and ESR Veronika Zahorodna are working in Polymer Institute, Slovak Academy of Sciences, Bratislava, Slovakia under the project secondments plan.

 
NANO2DAY project: Professor Maria Omastova, Polymenr Institue Slovak Academy of Science, visited Materials Research Centre, Kiev, Ukraine, July-August 2018

Professor Maria Omastova, Polymer Institute SAV, Bratislava, Slovakia, and Oleksiy Gogotsi, director of Materials Research Centre, Kiev, Ukraine,  July 2018Professor Omastova was acquainted with the activities and research infrastructure of MRC project partner, she held several seminars on polymer composites and talked about the experience and developments of her institute. 

 
The 6th International Conference on Novel Functional Carbon Nanomaterials at the 8th Forum on New Materials (CIMTEC 2018) in Perugia, Italy, June 11-14

Фото Yury Gogotsi.The 6th International Conference “Novel Functional Carbon Nanomaterials”within the 8th Forum on New Materials at CIMTEC 2018 held in Perugia, Italy,  highlighted recent achievements and challenges in the synthesis, structural control and modeling at the meso- and nano-scales of the variety of low-dimensional carbon allotropes including nanodiamonds, diamond-like carbon, fullerenes, nanotubes, graphene and graphene-related structures, as well as high surface area carbon networks, which are promising for a range of emerging applications in energy conversion and storage, water purification, high-speed nanoelectronics, optoelectronics, photonics, quantum information processing, quantum computing, biosensing, drug delivery, medical imaging, thermal management, catalysis, lubrication, etc.

 
1st International Conference on MXenes at Jilin University, Changchun, China

MXene conference 2018The meeting is the first international conference focusing on MXene materals, which is to bring scientists in the two-dimensional materials or energy area to interact and discuss the advances and challenges in various fields.

 
Our Congratulations to Prof. Gogotsi with Receiving an Honorary Doctorate from Kyiv Polytechnic Institute KPIthe National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute"

 Prof. Yury Gogotsi received an honorary doctorate from the National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic InstituteOn May 14th, 2018, Prof. Yury Gogotsi received an honorary doctorate from the National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute (NTUU “KPI”), Kiev, Ukraine.