We’re glad to welcome Dr. Abhishek Kumar at our Research group Seminar!
He obtained his Ph.D. at Institute Pascal, Clermont Auvergne University, on the Development, characterization and experimental validation of metallophthalocyanines based microsensors devoted to monocyclic aromatic hydrocarbons monitoring in air, under the supervision of Dr. Christelle Varenne and Dr. Jerome Brunet.
He’s now a post-doc Researcher at Institute of molecular chemistry, Universite de Bourgogne. His research topics includes Electrografting and Physical Vapor Deposition (PVD) of functional organic/inorganic nanomaterials for chemical sensors development (Under a collaborative COMICS project at UBFC, France).
Title : Molecular semiconductors based organic heterojunction sensors for redox gases detection
Abstract: Tuning of semiconducting properties in molecular materials like metal phthalocyanines (MPc) is a smart strategy to improve the gas sensing properties of sensing devices. In this endeavor, our research interests concern with development of organic heterojunction sensors based on bilayer of MPc, which benefit from high interfacial conductivity. Such high interfacial conductivity is caused by the mobile charges accumulation at the organic-organic interface in the heterostructure and is characterized by a non-Ohmic I-V profile [1, 2]. The high interfacial conductivity of heterojunction devices results in a reversible and a repeatable response towards successive exposure/recovery cycles of redox gases like ammonia. Remarkably, the sensor response is determined by the sublayer, despite gas interaction taking place on the top layer in the bilayer heterostructure sensing layer. The hetrojunction sensors can detect sub-ppm concentration of ammonia, making them suitable for real environment applications at room temperature. We are further diversifying the choices of materials and design of the heterojunction in particular by using electrosynthesis approaches  to improve the gas sensing properties of the heterojunction sensors. We are focusing on covalent electrografting and electropolymerization approaches to deposit low conducting organic films, directly on the sensor electrodes.
1. A. Kumar, R. Meunier-Prest, M. Bouvet, Sensors, 20, 4700, 2020.
2. Z. Şahin, R. Meunier-Prest, F. Dumoulin, A. Kumar, Ü. Isçi, M. Bouvet, Sens. Actuators B, 332, 129505, 2021.
3. A. Kumar, N. Alami Mejjati, R. Meunier-Prest, A. Krystianiak, O. Heintz, E. Lesniewska, C. H. Devillers, M. Bouvet, Chem. Eng. J., 429, 132453, 2022.