Interfacial and Surface Chemistry
The main thrust of our research is to understand solid-liquid and solid-solid interfaces involving modified surfaces and new materials with special emphasis on electrochemistry.
Exfoliated inorganic materials:There has been a spurt of activity in the area of 2D materials during the last several years. Since the advent of ‘graphene’ two dimensional, layered chalcogenides such as MoS2 have attracted attention as electrocatalysts for various redox reactions. Our interest has been in ternary chalcogenides and phosphochalcogenides such as MoSSe and PdPS for catalyzing oxygen reduction and oxygen evolution, chlorine evolution, carbon dioxide reduction in addition to hydrogen evolution from different electrolytes. Other layered materials based on exfoliated or expanded graphite (EG), ternary thiophosphates are also being looked at.
Transition metal nitrides and carbides:Transition metal nitrides and carbides such as titanium nitride (TiN), titanium carbide (TiC) and carbonitrides (TiCN) possess metallic conductivity, and are highly corrosion resistant. We have been interested in preparing nanostructures of various nitrides and carbides and explore their electrocatalytic properties.
Organic thin films - self assembled monolayers, (SAMs) and Langmuir-Blodgett films, (LB films):Our objective is to prepare stable, compact and well oriented 2-dimensional and 3-dimensional thin films and characterize them for applications such as electrocatalysis, sensing and devices such as FETs. Interfacial reactions at air-water interface under applied surface pressure are being explored as well.
Batteries, fuel cells and supercapacitors:We explore bi-functional catalysts and use them in metal-air batteries such as zinc-air and lithium-air systems. One of the holy grails that we are pursuing is on magnesium based rechargeable batteries. Our recent interests include gel based electrolytes and solid-state batteries based on novel catalysts. Hybrid capacitors combining a battery electrode and a capacitor electrode have been another area of interest. We are pursuing work on Pb-C based as well as Li-C based hybrid capacitors.
Molten deep eutectic electrolytes:Deep eutectic electrolytes based on amides have been an area of our interest in developing ionically conducting electrolytes for various electrochemical studies. Recently, we have electrodeposited GaN based on one such deep eutectic mixture. We are exploring the electrodeposition of various compound and simple semiconducting materials from deep eutectics in addition to using them as electrolytes for batteries.
Electrically conducting palladium selenide (Pd4Se, Pd17Se15, Pd7Se4) phases: synthesis and activity towards hydrogen evolution reactionK A Suresh, Muthu Austeria and S SampathChem. Comm., 52(1), 206, 2016DOI:
Primary and rechargeable zinc-air batteries using ceramic and highly stable TiCN as an oxygen reduction reaction electrocatalystV G Anju, K. Manjunatha, Muthu Austeria and S SampathJ. Mater. Chem.A, 4(14), 5258, 2016DOI:
The dual role of borohydride depending on reaction temperature: synthesis of iridium and iridium oxideK Chakrapani and S SampathChem. Comm, 51 (47), 9690, 2015
Active guests in the MoS2/MoSe2 host lattice: efficient hydrogen evolution using few-layer alloys of MoS2(1-x)Se2xV Kiran, Debdyuti M, Ramesh Naidu J and S SampathNanoscale, 6 (21), 12856, 2014
Equiatomic ternary chalcogenide: PdPS and its reduced graphene oxide composite for efficient electrocatalytic hydrogen evolutionSujoy Sarkar and S SampathChem. Comm, 50 (55), 7359, 2014
Ambient temperature deposition of gallium nitride / gallium oxynitride from a deep eutectic electrolyte, under potential controlSujoy Sarkar and S SampathChem. Comm, In Press, 2016
Representative (granted) patents:
Composition of electrode material in the form of a coating and a process thereofUS patent 8,343,572
Low cost electrochemical disposable sensor for measuring glycated hemoglobinUS patent 8,702,931
Formation of metallic patterns on a semiconductor wafer substrateEP 1954109 (A1)