Electrochemical Kinetics of Nanostructured Nb2O5Electrodes

Rus На русском Eng In English

Journal of The Electrochemical Society, 161(5) A718-A725 (2014)
0013-4651/2014/161(5)/A718/8/©The Electrochemical Society

Electrochemical Kinetics of Nanostructured Nb2O5 Electrodes

Jeremy Come,a,b Veronica Augustyn,c Jong Woung Kim,c Patrick Rozier,a,b Pierre-Louis Taberna,a,b Pavel Gogotsi,d,e Jeffrey W. Long,d,∗ Bruce Dunn,c,∗and Patrice Simona,b,∗,z

a Universit´ e Paul Sabatier, CIRIMAT UMR CNRS 5085, 31062 Toulouse Cedex 4, France
b R´ eseau sur le Stockage Electrochimique de l’Energie (RS2E), FR CNRS 3459, France
c Department of Materials Science & Engineering, University of California, Los Angeles, California 90095, USA
d Surface Chemistry Branch, Naval Research Laboratory, Washington, DC 20375, USA

Abstract

Pseudocapacitive charge storage is based on faradaic charge-transfer reactions occurring at the surface or near-surface of redox-active materials. This property is of great interest for electrochemical capacitors because of the substantially higher capacitance obtainable as compared to traditional double-layer electrode processes. While high levels of pseudocapacitance have been obtained with nanoscale materials, the development of practical electrode structures that exhibit pseudocapacitive properties has been challenging.

Schematic representations and corresponding electrochemical responses for ‘extrinsic’ and ‘intrinsic’ pseudocapacitors. a) Extrinsic pseudocapacitance where high specific capacitance values and pseudocapacitive behavior are observed only with thin films of the same material. The outer surface of the film dominates the response because of electrolyte access. A high concentration of defects at the surface (e.g., cation vacancies) will also contribute.This response is observed with most transition metal oxides; b) Intrinsic pseudocapacitance in Nb2O5. The pseudocapacitive behavior is preserved in thick films due to fast Li + transport within the bulk of the material

The present paper shows that electrodes of Nb2O5 successfully retain the pseudocapacitive properties of the corresponding nanoscale materials. For charging times as fast as one minute, there is no indication of semi-infinite diffusion limitations and specific capacitances of 380 F g −1 and 0.46 Fcm −2 are obtained in 40-μm thick electrodes at a mean discharge potential of 1.5 V vs Li+ /Li. In-situ X-ray diffraction shows that the high specific capacitance and power capabilities of Nb2O5 electrodes can be attributed to fast Li + intercalation within specific planes in the orthorhombic structure.

This intercalation pseudocapacitance charge-storage mechanism is characterized as being an intrinsic property of Nb2O5 that facilitates the design of electrodes for capacitive storage devices. Authors demonstrate the efficacy of these electrodes in a hybrid electrochemical cell whose energy density and power density surpass that of commercial carbon-based devices.

 © 2014 The Electrochemical Society. [DOI:10.1149/2.040405jes]

 

News from MRC.ORG.UA

Paper on Rheological Characteristics of 2D Titanium Carbide (MXene) Dispersions: A Guide for Processing MXenes

Processing guidelines for the fabrication of MXene films, coatings, and fibers have been established based on the rheological propertiesProcessing guidelines for the fabrication of MXene films, coatings, and fibers have been established based on the rheological properties.

 
Professor Yury Gogotsi will give a lecture on 2D materials MXenes in Stanford University

altProfessor Yury Gogotsi will give a lecture on 2D materials MXenes on MSE winter Colloquim in Materials Science and Engineering Department, Stanford University. 

 
MXene is one of the most sensitive gas sensors ever reported

MXene gas sensorsMXene is one of the most sensitive gas sensors ever reported that sniff out chemicals in the air to warn us about everything from fires to carbon monoxide to drunk drivers to explosive devices hidden in luggage have improved so much that they can even detect diseases on a person’s breath. Researchers from Drexel University and the Korea Advanced Institute of Science and Technology have made a discovery that could make our best “chemical noses” even more sensitive.

 
Professor Yury Gogotsi, Drexel University, USA, gave a plenary lecture at the 2018 Energy Future Conference in Sydney, Australia, 5-7 February 2018

Professor Gogotsi gave a plenary lecture on  two-dimensional materials MXenes

Professor Yury Gogotsi, Drexel University, USA,  gave a plenary lecture on February 06, 2018 and chaired a plenary session on February 05 at the Energy Future Conference (EF3 Conference 2018) in Sydney. EF3 Conference 2018 brought together scientists, engineers, policy makers, investors, academia, and industry to discuss the latest advances in energy technology. 

 
US-Czech Conference on Advanced Nanotechnology and Chemistry 17 th – 18th January 2018, Prague, Czech

US-Czeh conference on advanced nanotechnologiesMore than 30 speakers from USA and Czech were invited, among them also was invited outstanding scientist, professor Yury Gogotsi, founder director of Drexel Nanomaterials Institute in Drexel University, USA.

 
ICEnSM 2017. 2017 International Conference on Energy Storage Materials, Shenzhen, China, November 18-21, 2017

The First International Conference on Energy Storage Materials Professor Yury Gogotsi from Drexel University, USA, has won the 2017 Energy Storage Materials Award, which is awarded by the journal Energy Storage Materials. The Award will be presented to Professor Gogotsi at the ICEnSM 2017 (2017 International Conference on Energy Storage Materials), which will be held in Shenzhen, China, on Nov. 18-21, 2017.

 
Congratulations to professor Yury Gogotsi for being named 2017 Highly Cited Researcher in two categories!

altHis research ranks among the top 1% most cited works in his field and during its year of publication, earning the mark of exceptional impact. This year is the first time Yury Gogotsi made this list in two categories - Materials Science and Chemistry.

 
Nanodiamonds Can Prevent Lithium Battery Fires
 
Session dedicated to HORIZON-2020-MSCA-RISE project 690853 «Asymmetry of biological membrane: theoretical, experimental and applied aspects» ( assymcurv ), 5th International Conference "Nanobiophysics-2017"

ilt logoOleksiy Gogotsi, director of Materials Research Center presented join research on synthesis and biomedical applications of 2D carbides MXenes.

 
Congrats to professor Yury Gogotsi on winning the 2017 Changbai Mountain Friendship Award

Receiving a Changbai Mountain Friendship Award from the vice-governor of Jilin Province at the National Day foreign experts reception.Professor Yury Gogotsi from Drexel University, USA, received the 2017 Changbai Mountain Friendship Award from the vice-governor of Jilin Province at the National Day foreign experts reception.

 
Congarstulations to professor Yury Gogotsi from Drexel University, USA, who has won the 2017 Energy Storage Materials Award

yury gogotsiCongarstulations to professor Yury Gogotsi from Drexel University, USA, who has won the 2017 Energy Storage Materials Award,and is awarded by Energy Storage Materials journal.

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

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 most recent paper in Nature Materials researcher from Drexel University led by prof. Yury Gogotsi showed that Coulombic ordering reduces when the pores can accommodate only a single layer of ions. The non-Coulombic ordering is further enhanced in the presence of an applied electric potential. 

 
Researcers from Drexel University have developed a recipe that can turn electrolyte solution into a safeguard against the chemical process that leads to battery-related disasters

Recipe for Safer Batteries — Just Add DiamondsResearchers described a process by which nanodiamonds — tiny diamond particles 10,000 times smaller than the diameter of a hair — curtail the electrochemical deposition, called plating, that can lead to hazardous short-circuiting of lithium ion batteries.

 
Triangle Talks with Yury Gogotsi

alt

Yury Gogotsi is a researcher in the Drexel University Nanomaterials Group. He and his colleagues discovered a series of novel materials known as MXenes. 

 
Yury Gogotsi is the most influential scientist of modern Ukraine

altThe life of Yury Gogotsi is a constant back and forth between the top laboratories in the world, writing articles in the best scientific journals and research materials that can change the world around them.