Faraday Materials Laboratory (FaMaL)

“………..Bidya Dadaati Binayam.
“An investment in knowledge pays the best interest.”——-Benjamin Franklin

I. Lithium-ion batteries:

Rechargeable batteries have ushered an era of portable devices and consumer electronics, which has revolutionised our modern life-style. In this story, Lithium-ion batteries are frontrunner candidate, where the electrodes (both cathode and anode) are the cornerstone components. It is crucial to design new electrode materials in parallel to develop existing ones. Our research effort is focused on discovery of new class of polyanionic insertion compounds for the realization of high-voltage and/or high-capacity electrodes. Some such prominent systems include metal borates (LiMBO3), metal pyrophosphates (Li2MP2O7) and metal fluorosulphates (LiMSO4F). Tuning the crystal chemistry, it is now possible to get high-voltage redox operation with these new cathode materials.

* P Barpanda et al., Nature Materials, 10, 772 (2011).
* P Barpanda et al., J. Mater. Chem., 22, 13455 (2012).
* P Barpanda et al., J. Electrochem. Soc., 160, A3095 (2013).

II. Sodium-ion batteries:

Sodium-ion batteries form a complementary player to rechargeable Li-ion batteries, owing to their abundance and low cost. It can be ideal for large-scale grid storage applications. Off late, there has been tremendous exploration on various oxide as well as polyanionic insertion compounds for development of sodium-ion batteries. Polyanionic systems offer a great platform to design and discover new cathode materials with high voltage. Our effort is focused on novel metal sulphates and pyrophosphates family to develop novel cathode/ anode materials with tuneable redox voltage. It offers chance to realise high-voltage operation approaching the performance of Li-ion batteries.

* P Barpanda et al., Nature Communications, 5, 4358 (2014).
* P Barpanda et al., Chem. Mater., 26, 1297 (2014).
* P Barpanda et al., Chem. Mater., 25, 3480 (2013).

III. Activated Carbon Supercapacitors:

While rechargeable batteries provide superior energy-density, electrochemical capacitors (or supercapacitors) form a complementary class of electrochemical energy storage devices providing high power-density. There are two main kinds of supercapacitors: electrochemical double layer capacitors (EDLC) and pseudocapacitors. The EDLC store charge in form of double layer at the electrode interface, so morphology engineering and surface area increment are keys to increase the net capacitance. Activated carbons dominate the EDLC sector. Pseudocapacitors, majorly metal oxides, operate on interfacial charge transfer reaction mechanism. Our research has attempted to develop validated carbons to improve the net gravimetric and volumetric energy density.

* P Barpanda et al., Carbon, 49, 2538 (2011).
* P Barpanda et al., J. Electrochem. Soc., 156, A873 (2009).
* P Barpanda et al., Electrochim. Acta, 52, 7136 (2007).

IV. Synthesis of Ceramic Compounds (minor):

Materials synthesis form a core area of study of materials. There exists suites of solid-state as well as solvothermal synthesis to fabricate materials with tuneable size and morphology. Our group has ongoing effort on different low-temperature sustainable synthesis of various oxide and non-oxide ceramic materials. They include ionothermal, hydrothermal, polymer-assisted and solid-state methods. Also, we use two-step methods like (complexation) solution combustion synthesis and spray drying synthesis. They offer interesting variety of morphology for fundamental study of ceramic materials.

* P Barpanda et al., Acta Cryst., B69, 584 (2013).
* P Barpanda et al., J. Mater. Chem., 21, 10143 (2011).
* P Barpanda et al., Angew. Chem. Int. Ed., 50, 2526 (2011).
* P. Barpanda et al., J. Eur. Ceram. Soc., 26, 2603 (2006).

V. Micromagnetic Simulations (minor):

Magnetic nanostructures are widely used for many practical devices such as memory units and pseudo-spin-valves. Fundamental study of magnetic domains and their reversal upon application of external field/ current is beneficial to gauge the properties of these magnetic nano structures. We endeavour to investigate the magnetic structures and domain reversal in various nano magnetic architectures by using 3-dimensional Fast-Fourier Transformed micromagnetic simulation using Landau-Lifschitz-Gilbert (LLG) equations. It depicts the visualisation of fast domain switching and rough magnetic hysteresis behaviour in magnetic nano structures

* P Barpanda, Physica B, 406, 1336 (2011).
* P Barpanda et al., Jpn. J. Appl. Phys., 48, 103002 (2009).
* P Barpanda, Comp. Mater. Sci., 45, 240 (2009).