Namrata Deka - Academia.edu (original) (raw)

Uploads

Papers by Namrata Deka

Research paper thumbnail of Promising N, P Co‐doped Porous Carbon Materials as Metal‐Free Electrocatalyst for Oxygen Reduction Reaction in Alkaline Medium

Research paper thumbnail of Nitrogen and Sulfur Enriched Porous Carbon Materials with Trace Fe Derived from Hyper‐Crosslinked Polymer as an Efficient Oxygen Reduction Electrocatalyst

Research paper thumbnail of Facile hydrothermal synthesis of Au-Mn3O4 decorated graphene oxide nanocomposites for solid-state supercapacitor

Journal of Energy Storage

Research paper thumbnail of CCDC 1940030: Experimental Crystal Structure Determination

Research paper thumbnail of Nitrogen-Doped Microporous Carbons Synthesized from Indole-Based Copolymer Spheres for Supercapacitors and Metal-Free Electrocatalysis

Indole-based copolymer spheres serve as a precursor for the facile and easily scalable synthesis ... more Indole-based copolymer spheres serve as a precursor for the facile and easily scalable synthesis of a series of nitrogen-rich microporous carbons. The influence of chemical activation and carboniza...

Research paper thumbnail of Sulfonated Tetraphenylethylene-Based Hypercrosslinked Polymer as a Heterogeneous Catalyst for the Synthesis of Symmetrical Triarylmethanes via a Dual C–C Bond-Cleaving Path

Synlett, 2020

A sulfonic acid functionalized tetraphenylethylene-based hypercrosslinked polymer (THP-SO3H) with... more A sulfonic acid functionalized tetraphenylethylene-based hypercrosslinked polymer (THP-SO3H) with a well-developed porous network and accessible sulfonic acid sites was synthesized and characterized by different analytical techniques. The catalytic prowess of the synthesized material THP-SO3H was investigated in a challenging dual C–C bond-breaking reaction for the synthesis of symmetrical triarylmethanes (TRAMs) in high yield. The scope of the developed metal-free method was also explored with a wide variety of substrates. The organocatalyst can be easily recovered by filtration and reused up to five consecutive cycles without substantial loss in its catalytic efficacy.

Research paper thumbnail of Transforming waste polystyrene foam into N-doped porous carbon for capacitive energy storage and deionization applications

Applied Surface Science, 2020

Transforming waste polystyrene foam into N-doped porous carbon for capacitive energy storage and ... more Transforming waste polystyrene foam into N-doped porous carbon for capacitive energy storage and deionization applications,

Research paper thumbnail of Plastically Deformable and Exfoliating Molecular Crystals of a 2-D Coordination Polymer and Its Ligand

Crystal Growth & Design, 2019

Research paper thumbnail of Microporous Organic Polymer‐Derived Nitrogen‐Doped Porous Carbon Spheres for Efficient Capacitive Energy Storage

ChemElectroChem, 2019

A facile and template-free synthetic approach was utilized to obtain a series of nitrogen and oxy... more A facile and template-free synthetic approach was utilized to obtain a series of nitrogen and oxygen-doped microporous carbon spheres (CTS-X-700) from carbazole-terephthalaldehyde based copolymer spheres (CTS). The inherent spherical morphology of the co-polymer remained intact even after activation at high temperature (700°C). The synthesized materials exhibit BET surface area of up to 1340 m 2 g À 1 with an interconnected porous network consisting of ultramicropores and supermicropores along with a small amount of mesopores. Moreover, a good balance of heteroatom surface functionalities (N content up to 3.2 % and O content up to 12 %) was maintained without compromising the porosity by systematically varying the activation conditions. These features result in a high specific capacitance value of 407 F g À 1 at 1.0 A g À 1 in aqueous acid electrolyte with a three-electrode system and superior cycle stability of 100 % capacitance retention even after 10000 cycles. Furthermore, the high energy density (10.6 W h kg À 1 at a current density of 0.5 A g À 1) in an aqueous electrolyte of the assembled supercapacitor device further demonstrates the possible applications of the synthesized materials as high-performance energy storage devices.

Research paper thumbnail of Triazine based polyimide framework derived N-doped porous carbons: a study of their capacitive behaviour in aqueous acidic electrolyte

Materials Chemistry Frontiers, 2019

Nitrogen-doped porous carbons have been synthesized from triazine based polyimide frameworks usin... more Nitrogen-doped porous carbons have been synthesized from triazine based polyimide frameworks using ZnCl2 as an activating agent for electrochemical energy storage.

Research paper thumbnail of Nitrogen-Doped Porous Carbon Derived from Carbazole-Substituted Tetraphenylethylene-Based Hypercrosslinked Polymer for High-Performance Supercapacitor

ChemistrySelect, 2018

Cobalt-doped graphene-coupled hypercrosslinked polymers (Co-GHCP) have been successfully prepared... more Cobalt-doped graphene-coupled hypercrosslinked polymers (Co-GHCP) have been successfully prepared on a large scale, using an efficient RAFT (Reversible Addition-Fragmentation Chain Transfer Polymerization) emulsion polymerization and nucleophilic substitution reaction with Co (II) porphyrin. The Co-GHCP could be transformed into cobalt-doped porous carbon nanosheets (Co-GPC) through direct pyrolysis treatment. Such a Co-GPC possesses a typical 2D morphology with a high specific surface area of 257.8 m 2 g −1. These intriguing properties of transition metal-doping, high conductivity, and porous structure endow the Co-GPC with great potential applications in energy storage and conversion. Utilized as an electrode material in a supercapacitor, the Co-GPC exhibited a high electrochemical capacitance of 455 F g −1 at a specific current of 0.5 A g −1. After 2000 charge/discharge cycles, at a current density of 1 A g −1 , the specific capacitance increased by almost 6.45%, indicating the excellent capacitance and durability of Co-GPC. These results demonstrated that incorporation of metal porphyrin into the framework of a hypercrosslinked polymer is a facile strategy to prepare transition metal-doped porous carbon for energy storage applications.

Research paper thumbnail of Promising N, P Co‐doped Porous Carbon Materials as Metal‐Free Electrocatalyst for Oxygen Reduction Reaction in Alkaline Medium

Research paper thumbnail of Nitrogen and Sulfur Enriched Porous Carbon Materials with Trace Fe Derived from Hyper‐Crosslinked Polymer as an Efficient Oxygen Reduction Electrocatalyst

Research paper thumbnail of Facile hydrothermal synthesis of Au-Mn3O4 decorated graphene oxide nanocomposites for solid-state supercapacitor

Journal of Energy Storage

Research paper thumbnail of CCDC 1940030: Experimental Crystal Structure Determination

Research paper thumbnail of Nitrogen-Doped Microporous Carbons Synthesized from Indole-Based Copolymer Spheres for Supercapacitors and Metal-Free Electrocatalysis

Indole-based copolymer spheres serve as a precursor for the facile and easily scalable synthesis ... more Indole-based copolymer spheres serve as a precursor for the facile and easily scalable synthesis of a series of nitrogen-rich microporous carbons. The influence of chemical activation and carboniza...

Research paper thumbnail of Sulfonated Tetraphenylethylene-Based Hypercrosslinked Polymer as a Heterogeneous Catalyst for the Synthesis of Symmetrical Triarylmethanes via a Dual C–C Bond-Cleaving Path

Synlett, 2020

A sulfonic acid functionalized tetraphenylethylene-based hypercrosslinked polymer (THP-SO3H) with... more A sulfonic acid functionalized tetraphenylethylene-based hypercrosslinked polymer (THP-SO3H) with a well-developed porous network and accessible sulfonic acid sites was synthesized and characterized by different analytical techniques. The catalytic prowess of the synthesized material THP-SO3H was investigated in a challenging dual C–C bond-breaking reaction for the synthesis of symmetrical triarylmethanes (TRAMs) in high yield. The scope of the developed metal-free method was also explored with a wide variety of substrates. The organocatalyst can be easily recovered by filtration and reused up to five consecutive cycles without substantial loss in its catalytic efficacy.

Research paper thumbnail of Transforming waste polystyrene foam into N-doped porous carbon for capacitive energy storage and deionization applications

Applied Surface Science, 2020

Transforming waste polystyrene foam into N-doped porous carbon for capacitive energy storage and ... more Transforming waste polystyrene foam into N-doped porous carbon for capacitive energy storage and deionization applications,

Research paper thumbnail of Plastically Deformable and Exfoliating Molecular Crystals of a 2-D Coordination Polymer and Its Ligand

Crystal Growth & Design, 2019

Research paper thumbnail of Microporous Organic Polymer‐Derived Nitrogen‐Doped Porous Carbon Spheres for Efficient Capacitive Energy Storage

ChemElectroChem, 2019

A facile and template-free synthetic approach was utilized to obtain a series of nitrogen and oxy... more A facile and template-free synthetic approach was utilized to obtain a series of nitrogen and oxygen-doped microporous carbon spheres (CTS-X-700) from carbazole-terephthalaldehyde based copolymer spheres (CTS). The inherent spherical morphology of the co-polymer remained intact even after activation at high temperature (700°C). The synthesized materials exhibit BET surface area of up to 1340 m 2 g À 1 with an interconnected porous network consisting of ultramicropores and supermicropores along with a small amount of mesopores. Moreover, a good balance of heteroatom surface functionalities (N content up to 3.2 % and O content up to 12 %) was maintained without compromising the porosity by systematically varying the activation conditions. These features result in a high specific capacitance value of 407 F g À 1 at 1.0 A g À 1 in aqueous acid electrolyte with a three-electrode system and superior cycle stability of 100 % capacitance retention even after 10000 cycles. Furthermore, the high energy density (10.6 W h kg À 1 at a current density of 0.5 A g À 1) in an aqueous electrolyte of the assembled supercapacitor device further demonstrates the possible applications of the synthesized materials as high-performance energy storage devices.

Research paper thumbnail of Triazine based polyimide framework derived N-doped porous carbons: a study of their capacitive behaviour in aqueous acidic electrolyte

Materials Chemistry Frontiers, 2019

Nitrogen-doped porous carbons have been synthesized from triazine based polyimide frameworks usin... more Nitrogen-doped porous carbons have been synthesized from triazine based polyimide frameworks using ZnCl2 as an activating agent for electrochemical energy storage.

Research paper thumbnail of Nitrogen-Doped Porous Carbon Derived from Carbazole-Substituted Tetraphenylethylene-Based Hypercrosslinked Polymer for High-Performance Supercapacitor

ChemistrySelect, 2018

Cobalt-doped graphene-coupled hypercrosslinked polymers (Co-GHCP) have been successfully prepared... more Cobalt-doped graphene-coupled hypercrosslinked polymers (Co-GHCP) have been successfully prepared on a large scale, using an efficient RAFT (Reversible Addition-Fragmentation Chain Transfer Polymerization) emulsion polymerization and nucleophilic substitution reaction with Co (II) porphyrin. The Co-GHCP could be transformed into cobalt-doped porous carbon nanosheets (Co-GPC) through direct pyrolysis treatment. Such a Co-GPC possesses a typical 2D morphology with a high specific surface area of 257.8 m 2 g −1. These intriguing properties of transition metal-doping, high conductivity, and porous structure endow the Co-GPC with great potential applications in energy storage and conversion. Utilized as an electrode material in a supercapacitor, the Co-GPC exhibited a high electrochemical capacitance of 455 F g −1 at a specific current of 0.5 A g −1. After 2000 charge/discharge cycles, at a current density of 1 A g −1 , the specific capacitance increased by almost 6.45%, indicating the excellent capacitance and durability of Co-GPC. These results demonstrated that incorporation of metal porphyrin into the framework of a hypercrosslinked polymer is a facile strategy to prepare transition metal-doped porous carbon for energy storage applications.

Log In