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.

Representative Publications

• Ultrahigh-Rate Supercapacitors Based on 2-Dimensional, 1T MoS2xSe2(1-x) for AC Line-Filtering Applications
  A. Sellam, Rameshnaidu Jenjeti, and S. Sampath
  J. Phys. Chem. C 2018, 122(25), 14186-14191
   
  DOI: 10.1021/acs.jpcc.8b01593
• Few-Layer Iron Selenophosphate, FePSe₃: Efficient Electrocatalyst toward Water Splitting and Oxygen Reduction Reactions
  Debdyuti Mukherjee, Muthu Austeria P, and S. Sampath
  ACS Appl. Energy Mater. 2018, 1(1), 220-231
   
  DOI: 10.1021/acsaem.7b00101
• Stable, Rechargeable Lithium - Oxygen Battery in Liquid and Gel-Based Electrolytes
  V. G. Anju, S. Sampath
  Electrochimica Acta 2017, 252, 119-126
   
  DOI: 10.1016/j.electacta.2017.08.173
• Porous, Hyper-Crosslinked, 3D - Polymer as Stable, High Rate Capability - Cathode for Li ion Battery
  Debdyuti Mukherjee, Guruprasada Gowda Y.K., Harish M.N.K., S. Sampath
  ACS Appl. Mater. Int. 2017, 9, 19446-19454
   
  DOI: 10.1021/acsami.6b09575
• Two-Dimensional, Few-Layer Phosphochalcogenide, FePS3: A New Catalyst for Electrochemical Hydrogen Evolution over Wide pH Range
  Debdyuti Mukherjee, Muthu Austeria, S. Sampath
  ACS Energy Lett. 2016, 1, 367
   
  DOI: 10.1021/acsenergylett.6b00184
• Ambient Temperature Deposition of Gallium Nitride / Gallium Oxynitride From a Deep Eutectic Electrolyte, Under Potential Control
  S. Sarkar and S. Sampath
  Chem. Comm 2016, 52, 6407
   
  DOI: 10.1039/C6CC02487D