Publications by authors named "Shreyasi Chattopadhyay"

Covalent organic frameworks (COFs), featuring structural diversity, permanent porosity, and functional versatility, have emerged as promising electrode materials for rechargeable batteries. To date, amorphous polymer, COF, or their composites are mostly explored in lithium-ion batteries (LIBs), while their research in other alkali metal ion batteries is still in infancy. This can be due to the challenges that arise from large volume changes, slow diffusion kinetics, and inefficient active site utilization by the large Na or K ion.

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Fluorite mineral holds significant importance because of its optoelectronic properties and wide range of applications. Here, we report the successful exfoliation of bulk fluorite ore (calcium fluoride, CaF) crystals into atomically thin two-dimensional fluoritene (2D CaF) using a highly scalable liquid-phase exfoliation method. The microscopic and spectroscopy characterizations show the formation of (111) plane-oriented 2D CaF sheets with exfoliation-induced material strain due to bond breaking, leading to the changes in lattice parameter.

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Transition metal derivatives exhibit high theoretical capacity, making them promising anode materials for sodium-ion batteries. Sulfides, known for their superior electrical conductivity compared to oxides, enhance charge transfer, leading to improved electrochemical performance. Here, a hierarchical WS micro-flower is synthesized by thermal sulfurization of WO.

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Weak electrocatalytic activity of the LaSrMnO (LSM) oxygen electrode at medium and low temperatures leads to decreasing performance both in the solid oxide fuel cell (SOFC) mode and the solid oxide electrolysis cell (SOEC) mode. Herein, we design an ErBiO (ESB) functionalized LaSrMnO (labeled as LSM/ESB) oxygen electrode via a one-step co-synthesis modified Pechini method. The unique LSM/ESB with polarization resistance of only 0.

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The influence of adding nanoparticles on the ascast morphology of spin coated immiscible polystyrene/poly(methyl methacrylate) (PS/PMMA) thin films of different thickness () and composition (, volume ratio of PS to PMMA) has been explored in this article. To understand the precise effect of nanoparticle addition, the morphology of PS/PMMA thin blend films spin cast from toluene on a native oxide covered silicon wafer substrate was first investigated. It is seen that in particle free films, the generic morphology of the films remains nearly unaltered with increase in , for = 3:1 and 1:3.

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We designed an electrospinning synthesis protocol to obtain in situ, the mesoporous TiO nanofibers, which are surface-decorated with plasmonic AuAg nanoparticles (AuAg-mTNF-H). Such alloy nanoparticles are found to be partially exposed on the surface of the nanofibers. Characterization by HRTEM and EDS confirmed the formation of 1:1 AuAg alloy nanoparticles on the surface of TiO nanofibers with heterojunction at the interfaces.

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We observed that the hydrolysis-condensation reaction of precursors makes a significant difference in constructing ordered mesopores in electrospun ZrO2 nanofibers. Transmission-SAXS studies confirm the generation of uniform clusters of size ∼1.44 nm in the ZrOCl2·8H2O (inorganic salt) derived sol due to its relatively slow hydrolysis-condensation process.

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Development of advanced carbon cathode support with the ability to accommodate high sulfur (S) content as well as effective confinement of the sulfur species during charge-discharge is of great importance for sustenance of Li-S battery. A facile poly(vinylpyrrolidone)-assisted solvothermal method is reported here to prepare Mg-1,4-benzenedicarboxylate metal organic framework (MOF) from which mesoporous carbon is derived by thermal treatment, where the hexagonal sheetlike morphology of the parent MOF is retained. Existence of abundant pores of size 4 and 9 nm extended in three dimensions with zigzag mazelike channels helps trapping of S in the carbon matrix through capillary effect, resulting in high S loading.

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Hierarchical anatase titania (TiO2) with a hollow spherical architecture decorated with functionalized carbon dots (C(F)@THS) was synthesized by a solvothermal decomposition of titanium(IV) isopropoxide (TTIP) in the presence of a solution mixture containing thiourea and citric acid. Interestingly, the concomitant presence of thiourea and citric acid has been found to be essential to obtain such hierarchical hollow architecture because individual constituents produced non-hollow spheres when hydrothermally treated with TTIP. The co-existence of these two constituents also accelerates the growth of hollow spheres.

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Exploring new electrode materials is the key to realize high performance energy storage devices for effective utilization of renewable energy. Natural clays with layered structure and high surface area are prospective materials for electrical double layer capacitors (EDLC). In this work, a novel hybrid composite based on acid-leached montmorillonite (K10), multi-walled carbon nanotube (MWCNT) and manganese dioxide (MnO2) was prepared and its electrochemical properties were investigated by fabricating two-electrode asymmetric supercapacitor cells against activated carbon (AC) using 1.

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