Thara's Research Group
Aqueous Na-ion/S batteries
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Aqueous rechargeable Na-ion/S batteries are considered as a next-generation energy storage system. However, a low water stability window, high solubility of polysulfides, and loss of the active material in the form of H S gas results in poor cycling stability and hinder its widespread application. The performance of these battery systems heavily depends on the characteristics of both electrode and electrolyte and more importantly their interfacial chemistry. Therefore, our research work is focused on designing of efficient sulfur host and tuning or modification of the electrolyte to achieve high cycling stability and high full cell energy density.
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Our research interests:
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Designing highly stable abode materials.
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Understanding the mechanism of polysulfide dissolution and the effect of the various components on polysulfide dissolution by electrochemical and spectroscopic techniques.
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Developing a new, stable, and high voltage aqueous electrolyte.
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Stable SEI formation to achieve durable cycling stability.
Publications:
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M. Kumar, A. K. Padhan, D. MandalÙ and T. C. NagaiahÙ, “An elemental sulfur/CoS - ionic liquid-based anode for high-performance aqueous sodium-ion batteries”. Energy Storage Mater., 2022, 45, 1052-1061.
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M. Kumar and T. C. NagaiahÙ, “High energy density aqueous rechargeable sodium-ion/sulfur batteries in ‘water in salt” electrolyte”. Energy Storage Mater., 2022,49, 390-400.
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M. Kumar, N. Thakur, A. Bordoloi, A. Yadav, S. Jha, D. Bhattacharyya, D. Mandal and T. C. NagaiahÙ, “High-performance aqueous sodium-ion/sulfur battery using elemental sulfur”. J. Mater. Chem. A, 2022,10, 11394-11404. (Published as a Hot Article).
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M. Kumar and T. C. NagaiahÙ, “Tuning the interfacial chemistry for stable and high energy density aqueous sodium-ion/sulfur batteries”. J. Mater. Chem. A, 2022, (DOI:https://doi.org/10.1039/D2TA01776H).
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Aqueous Zn-CO2 batteries
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CO is a bane to the environment, and its elimination is not easy. Thus, converting it into value-added fuels or harmless chemicals by a greener electrochemical approach gives us a hope of regenerating the healthy atmosphere. However, external power and lack of the catalyst with selective product formation are a major roadblocks, causing wastage of electricity resources and a less eco-efficient economy. The electrochemical CO reduction can be combined with energy storage and conversion in an aqueous Zn-CO battery cell that combines cathodic electrochemical CO reduction and anodic Zn oxidation, which sustainably export electricity and simultaneously convert CO into value-added chemicals. However low power density of Zn-CO hindered its widespread application. Therefore, our work is focused on designing a high-power density Zn-CO battery for practical application.
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Our research interests:
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Our group is working on the formation of value-added fuels like methanol from electrochemical CO reduction.
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Designing of the bifunctional catalysts for high power density Zn-CO battery.
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Understanding the mechanism by fast scanning and local electrocatalytic activity by SECM.
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Aqueous Zn-S/Fe-S batteries
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To develop an efficient next-generation energy storage device using an environment-friendly aqueous electrolyte, it is necessary to uplift the energy density and capacity of this aqueous battery comparable to the commercially available batteries. In this regard, Zn-S and Fe-S batteries possess various benefits of high energy density, cost-effectiveness, and high capacity. The theoretical capacity of Zn/Fe anode and sulfur cathode material will provide a high energy density with the safety of the aqueous electrolyte. However, the concept of using the Fe-S and Zn-S as an energy storage system remains relatively unexplored. Recently, we are exploring various possibilities of designing anode, cathode material, and electrolytes for Zn-S/Fe-S batteries to cherish the benefit of high energy density and capacity.
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Our research interests:
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Our group is working on designing the cathode materials and electrolytes.
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Formation of stable SEI on Zn/Fe anode surface, and corrosion studies of Zn anode by micro electrochemistry.
Hybrid battery supercapacitors
A battery supercapacitor hybrid device combines the advantages of the high energy density of batteries and the high-power density of supercapacitor in a single device. However, the capacity and kinetic imbalance between the two types of electrode material reduced its performance. In this regard, our group is actively working on developing new electrode materials and various possible approaches to designing a hybrid battery-supercapacitor to efficiently combine the merits of both. So that the resultant device contributes high energy and power density, long cycle life, and fast charge-discharge rates to store and deliver energy.
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Publications:
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M. Kumar and T. C. NagaiahÙ, “A unique 2.1 V “water in salt” elemental sulfur based Na-ion hybrid storage capacitor”. J. Mater. Chem. A, 2022,10, 10979-10989.
Non-aqueous Li-S batteries
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The capacity and energy density of traditional lithium-ion batteries (LIBs) reaches a bottleneck. Therefore, it is essential to discover a new battery system with a higher theoretical capacity. In this regard, lithium−sulfur (Li-S) batteries are becoming a fascinating choice because of the high theoretical capacity (1675 mAh g ) of sulfur. The energy density of these batteries is almost three times superior to LIBs. However, the problem of polysulfide shuttling, the insulating nature of discharge products, and poor sulfur utilization is still a big concern. Therefore our group is continuously working on designing a cost-effective, highly conductive, and efficient catalyst for polysulfide anchoring and accelerated sulfur redox kinetics to improve the performance of Li-S batteries.
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Publications:
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1. V. Singh, A. K. Padhan, S. D. Adhikary, A. Tiwari, D. Mandal and T. C. Nagaiah, Poly(ionic liquid)–zinc polyoxometalate composite as a binder-free cathode for high-performance lithium-sulfur batteries J. Mater. Chem. A, 2019, 7, 3018-3023.