Nanostructured Electrodes as Random Arrays of Active Sites

Modeling and Theoretical Characterization

Significance 

Nanostructured materials are gaining popularity as the material of choice for the design of new electrochemical sensors, catalytic devices, capacitors etc. Consequently, nanostructured electrochemical interfaces (NECI) are frequently being encountered in practice. Recent reports have revealed that for various NECI applications, the location of the active sites cannot be controlled thus leading to disordered surface structures referred as random arrays of active sites. Theoretically, random arrays are complicated by the fact that taking into account exact positions of the active sites with respect to each other is either difficult or impossible. Nonetheless, the electrochemical response of the system can be modeled employing statistical information about active sites dispersal.

In this view, scientists from the CNRS – Ecole Normale Superieure, PSL Research University – Sorbonne University in France: Dr. Alexander Oleinick, Dr. Oleksii Sliusarenko, Professor Irina Svir and Professor Christian Amatore provided expert opinion on modelling of non-ordered electrochemical systems and statistical characterization of active sites distribution from electrochemical measurements. They aspired to unravel the main principles underlying the theoretical description of the behavior of regular and random arrays of nanometric active sites and introduced efficient and precise approaches for modeling and predicting the electrochemical behavior of nanostructured electrodes with active sites of identical sizes. Their work is currently published in Journal of The Electrochemical Society.

In their review, the authors presented the main principles governing behavior of regular and random arrays of nanometric active sites and how these principles can be used for theoretical description of these systems. In their approach, the researchers first studied electrochemical behavior of single electrodes within unit cells of various shapes. Insights obtained from these studies allowed the team to address significantly more complex electrode assemblies. Remarkably, they showed further that the presented concepts could be applied for establishing efficient and accurate semi-analytical approximation of ordered as well as non-ordered arrays responses under diffusion limited conditions when they involve the common situation of active sites with identical sizes.

In summary, the approach reviewed was seen to allow for an efficient modeling and prediction of the electrochemical behavior of nanostructured electrodes with active sites of identical sizes dispersed onto an inert substrate as well as for extracting statistical spatial information from electrochemical signature of an array. In fact, the researchers noted that their approximation was general and, as exemplified for different type of arrays, could be employed for describing the behavior of any array involving arbitrary distributions of their active sites onto the substrate surface. In a statement to Advances in Engineering, Professor Christian Amatore, one of the corresponding authors highlighted that their work demonstrated an efficient approach which allows statistical characterization of active sites distributions of any array based on chronoamperometric data. The further research on characterization of random arrays under more complex and experimentally relevant situations is in process in the team.

Nanostructured Electrodes as Random Arrays of Active Sites: Modeling and Theoretical Characterization - Advances in Engineering

About the author

Professor Christian Amatore, 68, was educated at Ecole Normale Supérieure (ENS), the leading French center for higher education and research. When he acted as the Director of the Chemistry Department of ENS as ENS Professor of Chemistry, then holding the former position of Louis Pasteur, he brought ENS back to the front international scene in chemistry by designing the present configuration of its Chemistry Department that encompasses several chemical fields from theoretical physical chemistry to bio-organic chemistry with a special focus on chemical issues of importance in many life functions. He is now Emeritus Director of Research in CNRS and Distinguished Professor in the University of Xiamen, Fujian, China.

He is Full Member of the French Academy of Sciences where he served as a vice-President in charge of Education, Foreign Member of the Chinese Academy of Sciences, Member of the Academia Europaea, Member of The Third World Academy of Sciences, Foreign Member of the Brazilian Academy of Sciences, Honorary Fellow of The Royal Society of Chemistry and of the Chinese Chemical Society, Honorary Member of the Israeli Chemical Society, Distinguished Scientist of the French Chemical Society (SCF), Fellow of the International Society of Electrochemistry (ISE) and of the Electrochemical Society (ECS), President and now Past President of the International Society of Electrochemistry.

He served as one of the twenty members of the High Council of Science and Technology, which advised the French Presidents Jacques Chirac and Nicolas Sarkozy on scientific and technological matters. He has been thrice knighted by the French Republic in the national Orders of Merits and of Legion d’Honneur for his scientific achievements, and in the Order of Academic Palms.

Dr. Amatore’s primary research contributions are disclosed in 500 publications accumulating more than 25,000 citations and corresponding to a h-index of 80 (ISI Web of Science, March 2020) with an average citations rate larger than 1,250 per year over the past 5 years.

About the author

Professor Irina Svir received her Ph.D. in 1994 and her Dr. Sci. degree (Habilitation) in 2002, both in applied mathematics, in Kharkiv, Ukraine, where she became Full Professor. She currently works in France at Ecole Normale Superieure as Research Director in CNRS. Her main research interests involve mathematical modeling of physicochemical phenomena and the use of numerical methods for solving complex electrochemical problems. She is a co-author and co-developer of several innovative scientific softwares, including KinFitSim and KISSA-software, as well as over than 90 articles published in international journals with reference to h = 22.

About the author

Dr. Oleksii Sliusarenko obtained his M.S. degree in Applied Physics from Kharkiv National University (Ukraine) in 2007 with the specialty of Applied Physics and Ph.D. in 2012 in Theoretical Physics. He now works at the Basque Center for Applied Mathematics (Spain) as a postdoctoral fellow. His research activities include numerical and analytical methods of statistical and stochastical physics and their applications in chemistry, environmental problems and machinery.

About the author

Dr. Alexander Oleinick is a researcher of The French National Centre for Scientific Research (CNRS) and works in the “PASTEUR” lab founded by CNRS, École Normale Supérieure – PSL University and Sorbonne University in Paris, France. He obtained his PhD degree in applied mathematics from Kharkov National University of Radioelectronics (Kharkov, Ukraine) in 2005 and defended his habilitation (HDR) in chemistry at Pierre and Marie Curie University (Paris, France) in 2016. His researches encompass the field of mathematical modelling and simulations for investigating physico-chemical and biological processes.

Reference

Alexander Oleinick, Oleksii Sliusarenko, Irina Svir, Christian Amatore. Review—Nanostructured Electrodes as Random Arrays of Active Sites: Modeling and Theoretical Characterization. Journal of The Electrochemical Society, 2020, volume 167: 013530.

Go To Journal of The Electrochemical Society

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