Dr. Moumita Kotal

@iitkgp.ac.in

Senior Research Associate, School of Nanoscience and Technology
Indian Institute of Technology, Kharagpur

EDUCATION

PhD-IIT Kharagpur

RESEARCH INTERESTS

Supercapacitors, Ionic Actuators, Triboelectric nanogenerator, Photocatalysis, Polymer Nanocomposites and blends; Carbon Nanostructures, Graphene, Metal-organic framework

Scopus Publications

2558

Scholar Citations

Scholar h-index

Scholar i10-index

Scopus Publications

Cathode materials for rechargeable lithium batteries: Recent progress and future prospects
Moumita Kotal, Sonu Jakhar, Sandipan Roy, and Harish K. Sharma
Elsevier BV

Graphenelated Cobalt Nanoparticle Embedded Nitrogen-Doped Carbon Nanotubes for Efficient Visible-Light Photocatalysis
Moumita Kotal, Aashima Sharma, Sonu Jakhar, Vinit Mishra, Sandipan Roy, Subash Chandra Sahoo, Harish K. Sharma, and Surinder Kumar Mehta
American Chemical Society (ACS)
Visible-light-assisted photocatalysis for the degradation of organic pollutants has recently become an efficient green approach in the field of environmental pollution abatement. Herein, graphene-templated zeolite-imidazolate framework (ZIF-67) derived, Co nanoparticle embedded, nitrogen-doped carbon nanotubes (G-Co-NCNTs) have been developed as a promising, inexpensive, high-yield photocatalyst to decompose reactive black 5 (RB5) under visible light irradiation. Morphology and structural characterization studies revealed that the growth of NCNTs along with pyridinic N content and the abundance of meso-micropores were greater in G-Co-NCNT than in Co-NCNT itself, suggesting the importance of graphene for in situ growth of ZIF-67 on GO. DRS study reveals that G-Co-NCNT exhibited low optical band gap (∼2.9 eV), assisting in the promotion of photoresponse behavior. The photocatalytic activity of our designed G-Co-NCNT hybrid showed excellent dye degradation ability (98%) after 60 min with a wide range of pH tolerance and promising reusability even after five cycles (93%) under visible light, while Co-NCNT demonstrated only about 62% dye degradation, further implying the importance of graphene and oriented NCNTs for dye degradation. Therefore, the G-Co-NCNT hybrid could be used as an efficient photocatalyst for the remediation of organic pollutants in wastewater.

Metal–Organic Framework-Derived Graphitic Nanoribbons Anchored on Graphene for Electroionic Artificial Muscles
Moumita Kotal, Rassoul Tabassian, Sandipan Roy, Saewoong Oh, and Il‐Kwon Oh
Wiley

Mechanochemical Synthesis of a New Triptycene-Based Imine-Linked Covalent Organic Polymer for Degradation of Organic Dye
Kawal Preet, Girish Gupta, Moumita Kotal, Sushil Kumar Kansal, Deepak B. Salunke, Harish K. Sharma, Subash Chandra Sahoo, Pascal Van Der Voort, and Sandipan Roy
American Chemical Society (ACS)
In the present work, a novel triptycene-based imine-linked covalent organic polymer (TP-COP) was designed and synthesized via room-temperature, solvent-free mechanochemical grinding. The as-synthesized TP-COP material was fully characterized by Fourier transform infrared spectroscopy, solid-state NMR, field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Brunauer–Emmett–Teller method, thermogravimetric analysis, diffuse reflectance spectroscopy (DRS), and electron paramagnetic resonance (EPR). The HRTEM image of TP-COP clearly indicates the presence of graphene-like layered morphology (exfoliated layers). The DRS study reveals that TP-COP exhibited a low optical band gap value of 2.49 eV, implying its semiconducting nature. Further, the EPR study confirmed the semiconducting behavior of TP-COP through the generation of free radicals. These findings suggest that TP-COP could be used as an efficient photocatayst for the degradation of organic dye (RhB...

Collectively Exhaustive Electrodes Based on Covalent Organic Framework and Antagonistic Co-Doping for Electroactive Ionic Artificial Muscles
Sandipan Roy, Jaehwan Kim, Moumita Kotal, Rassoul Tabassian, Kwang J. Kim, and Il‐Kwon Oh
Wiley

Electroactive Artificial Muscles Based on Functionally Antagonistic Core–Shell Polymer Electrolyte Derived from PS-b-PSS Block Copolymer
Van Hiep Nguyen, Jaehwan Kim, Rassoul Tabassian, Moumita Kotal, Kiwoo Jun, Jung‐Hwan Oh, Ji‐Myeong Son, Muhammad Taha Manzoor, Kwang Jin Kim, and Il‐Kwon Oh
Wiley
Abstract Electroactive ionic soft actuators, a type of artificial muscles containing a polymer electrolyte membrane sandwiched between two electrodes, have been intensively investigated owing to their potential applications to bioinspired soft robotics, wearable electronics, and active biomedical devices. However, the design and synthesis of an efficient polymer electrolyte suitable for ion migration have been major challenges in developing high‐performance ionic soft actuators. Herein, a highly bendable ionic soft actuator based on an unprecedented block copolymer is reported, i.e., polystyrene‐b‐poly(1‐ethyl‐3‐methylimidazolium‐4‐styrenesulfonate) (PS‐b‐PSS‐EMIm), with a functionally antagonistic core–shell architecture that is specifically designed as an ionic exchangeable polymer electrolyte. The corresponding actuator shows exceptionally good actuation performance, with a high displacement of 8.22 mm at an ultralow voltage of 0.5 V, a fast rise time of 5 s, and excellent durability over 14 000 cycles. It is envisaged that the development of this high‐performance ionic soft actuator could contribute to the progress toward the realization of the aforementioned applications. Furthermore, the procedure described herein can also be applied for developing novel polymer electrolytes related to solid‐state lithium batteries and fuel cells.

Highly Bendable Ionic Soft Actuator Based on Nitrogen-Enriched 3D Hetero-Nanostructure Electrode
Moumita Kotal, Jaehwan Kim, Rassoul Tabassian, Sandipan Roy, Van Hiep Nguyen, Nikhil Koratkar, and Il-Kwon Oh
Wiley

Functionally Antagonistic Hybrid Electrode with Hollow Tubular Graphene Mesh and Nitrogen-Doped Crumpled Graphene for High-Performance Ionic Soft Actuators
Rassoul Tabassian, Jaehwan Kim, Van Hiep Nguyen, Moumita Kotal, and Il-Kwon Oh
Wiley

Electroionic Antagonistic Muscles Based on Nitrogen-Doped Carbons Derived from Poly(Triazine-Triptycene)
Sandipan Roy, Jaehwan Kim, Moumita Kotal, Kwang Jin Kim, and Il-Kwon Oh
Wiley
Abstract Electroactive soft actuators and bioinspired artificial muscles have received burgeoning interest as essential components in future electronic devices such as soft haptic‐feedback systems, human‐friendly wearable electronics, and active biomedical devices. However, important challenging issues including fast response time, ultralow input power, robust operation in harsh environments, high‐resolution controllability, and cost‐effectiveness remain to be resolved for more practical applications. Here, an electroionic antagonistic artificial muscle is reported based on hierarchically porous nitrogen‐doped carbon (HPNC) electrodes derived from a microporous poly(triazine‐triptycene) organic framework (PtztpOF). The HPNC, which exhibits hierarchically micro‐ and mesoporous structures, high specific capacitance of 330 F g−1 in aqueous solution, large specific surface area of 830.46 m2 g−1, and graphitic nitrogen doping, offers high electrical conductivity of 0.073 MS m−1 and outstanding volumetric capacitance of 10.4 MF m−3. Furthermore, it is demonstrated that a novel electroionic antagonistic muscle based on HPNC electrodes successfully displays extremely reliable and large bending deformations and long‐term durability under ultralow input voltages. Therefore, microporous polymer or covalent organic frameworks can be applied to provide significant improvements in electroactive artificial muscles, which can play key roles as technological advances toward bioinspired actuating devices required for next‐generation soft and wearable electronics.

Soft but Powerful Artificial Muscles Based on 3D Graphene–CNT–Ni Heteronanostructures
Jaehwan Kim, Seok-Hu Bae, Moumita Kotal, Tyler Stalbaum, Kwang J. Kim, and Il-Kwon Oh
Wiley
Bioinspired soft ionic actuators, which exhibit large strain and high durability under low input voltages, are regarded as prospective candidates for future soft electronics. However, due to the intrinsic drawback of weak blocking force, the feasible applications of soft ionic actuators are limited until now. An electroactive artificial muscle electro-chemomechanically reinforced with 3D graphene-carbon nanotube-nickel heteronanostructures (G-CNT-Ni) to improve blocking force and bending deformation of the ionic actuators is demonstrated. The G-CNT-Ni heteronanostructure, which provides an electrically conductive 3D network and sufficient contact area with mobile ions in the polymer electrolyte, is embedded as a nanofiller in both ionic polymer and conductive electrodes of the ionic actuators. An ionic exchangeable composite membrane consisting of Nafion, G-CNT-Ni and ionic liquid (IL) shows improved tensile modulus and strength of up to 166% and 98%, respectively, and increased ionic conductivity of 0.254 S m-1 . The ionic actuator exhibits enhanced actuation performances including three times larger bending deformation, 2.37 times higher blocking force, and 4 h durability. The electroactive artificial muscle electro-chemomechanically reinforced with 3D G-CNT-Ni heteronanostructures offers improvements over current soft ionic actuator technologies and can advance the practical engineering applications.

Nanohole-structured, iron oxide-decorated and gelatin-functionalized graphene for high rate and high capacity Li-Ion anode
Si-Hwa Lee, Moumita Kotal, Jung-Hwan Oh, Palanichamy Sennu, Sung-Ho Park, Yun-Sung Lee, and Il-Kwon Oh
Elsevier BV
Abstract Graphene hybrid nanostructures have emerged as potential candidates as efficient anode materials for lithium-ion batteries. However, two-dimensional plate-like structures protect rapid transport of lithium ions through the thickness direction, resulting in a long pathway of lithium ions and low rate performances. Here, we report a nanohole-structured, iron oxide-decorated and gelatin-functionalized graphene (D-N-GG) for high rate and high capacity lithium-ion anode. Initially, to produce effective path way of lithium ions, physical nanoholes on the graphene layers were generated by microwave-irradiated iron nanoparticles. And then, the gelatin was used to form nitrogen-doped graphene having more active sites for lithium ion storage. Finally, D-N-GG was synthesized by two-step microwave irradiations shows a three-dimensional interconnected mesoporous structure with a uniform decoration of iron oxide nanoparticles on the nanohole-structured graphene, resulting in highly conductive networks and short diffusion lengths for effective lithium ion transport. As a result, the obtained D-N-GG nanostructure delivered a reversible capacity of 924 mAh g −1 even over 40 cycles along with a coulombic efficiency in excess of 99%. Especially, even after 65 cycles with variable current density of 100–800 mA g −1 , the discharge capacity returned to 1096 mAh g −1 , which indicated a very stable and high-rate cyclic performance.

Self-assembly and morphological control of three-dimensional macroporous architectures built of two-dimensional materials
Ji-Eun Kim, Jung-Hwan Oh, Moumita Kotal, Nikhil Koratkar, and Il-Kwon Oh
Elsevier BV
Abstract The three-dimensional (3D) macroscopic assembly of tailored porous architectures built of graphene derivatives or other two-dimensional (2D) materials has attracted great attention in both academia and industry. The reason being that such 3D assemblies with controlled morphology can provide ultra-large accessible surface areas and interconnected networks, as well as preventing the undesirable re-stacking phenomena of 2D materials. Herein, we review the synthetic routes and formation mechanism of bulk gel and interface mediated 3D architectures made of diverse 2D materials encompassing both graphene derivatives and non-graphene 2D materials. We also suggest universal strategies that can provide useful insight into application-oriented architecture design. The gelation mechanism is explained in detail; it involves controlled destabilization of the suspension involving a delicate balance between attractive and repulsive interactions. Further, interface mediated self-assembly processes between liquid-solid, liquid-liquid, liquid-gas, and ice-water phases are discussed with a view to tailoring 3D layered and interconnected morphologies. Finally, we highlight the demand for future applications of 2D material-based 3D macroporous architectures. Despite recent progress, more precise control strategies for tuning surface area, pore size distribution, orientation/interconnectivity of pores, density of architectures, and mechanical stability, remain as key scientific and technological barriers that must be addressed to enable practical applications. Further, an important frontier area for future research will involve multilateral hybridization, involving diverse combinations of materials, morphologies, and assembly methods This will provide researchers a multi-dimensional toolbox to access hitherto unavailable properties of 2D material-based 3D architectures for a whole host of applications.

Sulfur and nitrogen co-doped holey graphene aerogel for structurally resilient solid-state supercapacitors under high compressions
Moumita Kotal, Hyunjun Kim, Sandipan Roy, and Il-Kwon Oh
Royal Society of Chemistry (RSC)
A highly compressible, conductive nitrogen and sulfur co-doped holey graphene aerogel (NS-HGA) is developed for structurally resilient solid-state supercapacitors under high compressions.

Recent progress in multifunctional graphene aerogels
Moumita Kotal, Jaehwan Kim, Junghwan Oh, and Il-Kwon Oh
Frontiers Media SA
Two dimensional (2D) graphene has become one of the most intensively explored carbon allotropes in materials science owing to attractive features like its outstanding physicochemical properties. In order to further realize practical applications, the fabrication of self-assembled 2D individual graphene sheets into 3D graphene aerogels (GAs) with special structures and novel functions, is now becoming essential. Moreover, GAs are ideal as supports for the introduction of nanoparticles, polymers, and functional materials to further enhance their applications in broad areas. GAs have light weight, large surface area, good compressibility, extensibility, and high electrical conductivity. They have been used as efficient electrodes for batteries, in supercapacitors, and in sensors and actuators. This critical review mainly addresses recent progress in the methods used for their syntheses, their properties, and applications for energy storage, and in sensors and actuators. Furthermore, to assist advanced research for practical applications of these emerging materials, the technical challenges are discussed, and future research directions are proposed.

Sulfur and Nitrogen Co-Doped Graphene Electrodes for High-Performance Ionic Artificial Muscles
Moumita Kotal, Jaehwan Kim, Kwang J. Kim, and Il-Kwon Oh
Wiley
UNLABELLED Sulfur and nitrogen co-doped graphene electrodes for bioinspired ionic artificial muscles, which exhibit outstanding actuation performances (bending strain of 0.36%, 4.5 times higher than PEDOT PSS electrodes, and 96% of initial strain after demonstration over 18 000 cycles), provide remarkable electro-chemo-mech anical properties: specific capacitance, electrical conductivity, and large surface area with mesoporosity.

Functionalized graphene with polymer as unique strategy in tailoring the properties of bromobutyl rubber nanocomposites
Moumita Kotal, Shib Shankar Banerjee, and Anil K. Bhowmick
Elsevier BV
Abstract The reinforcement of polymers by graphene has generated great interest in recent years; however, very few investigations have been devoted to the reaction between graphene and elastomers. In the present work, a new “grafting to” approach for the formation of high-performance graphene/bromo butyl rubber (BIIR) nanocomposites was developed for tyre inner liner application by grafting of BIIR on simultaneously functionalized and reduced graphene oxide surface (BIIR-g-GO-PPD). This was then followed by their dispersion in BIIR matrix. For comparison, BIIR grafted graphene was also used. The properties of the functionalized graphene and their nanocomposites were thoroughly investigated. This promising pathway led to higher degree of exfoliation of BIIR-g-GO-PPD in the BIIR matrix as confirmed by the corresponding morphologies. Such exfoliation and stronger interaction resulted in remarkable enhancement in tensile strength (200%), storage modulus (189%), thermal stability (17 °C) and permittivity (460%) and drastic improvement in gas impermeability (44%) in their corresponding nanocomposites over neat BIIR. Therefore, functionalization and stitching of graphene followed by grafting with polymer offer high-performance BIIR/graphene nanocomposites as new tyre materials.

Defect engineering route to boron nitride quantum dots and edge-hydroxylated functionalization for bio-imaging
Jung-Hwan Jung, Moumita Kotal, Min-Ho Jang, Junseok Lee, Yong-Hoon Cho, Won-Jong Kim, and Il-Kwon Oh
Royal Society of Chemistry (RSC)
A defect engineering method was developed using physical energy sources to synthesize boron nitride quantum dots (BNQDs) for bioimaging applications.

Polymer nanocomposites from modified clays: Recent advances and challenges
Moumita Kotal and Anil K. Bhowmick
Elsevier BV
Abstract Since the end of the last century, the discovery of polymer nanocomposites and their ever-expanding use in various applications has been the result of continuous developments in polymer science and nanotechnology. In that regard, progress in developments on the use of modified natural and synthetic clays for designing polymer nanocomposites is presented herein. The modified clays used in composite preparation include natural clays such as montmorrilonite, hectorite, sepiolite, laponite, saponite, rectorite, bentonite, vermiculite, biedellite, kaolinite, and chlorite, as well as synthetic clays including various layered double hydroxides, synthetic montmorrilonite, hectorite, etc. The preparation, structure and properties of polymer nanocomposites using the modified clays are discussed. Even at a low loading, these composites are endowed with remarkably enhanced mechanical, thermal, dynamic mechanical, adhesion and barrier properties, flame retardancy, etc. The properties of the nanocomposites depend significantly on the chemistry of polymer matrices, nature of clays, their modification and the preparation methods. The uniform dispersion of clays in polymer matrices is a general prerequisite for achieving improved mechanical and physical characteristics. Various theories and models used to design polymer/clay nanocomposites have also been highlighted. A synopsis of the applications of these advanced, high-performance polymer nanocomposites is presented, pointing out gaps to motivate potential research in this field.

Coordination Polymers Containing Tubular, Layered, and Diamondoid Networks: Redox, Luminescence, and Electron Paramagnetic Resonance Activities
Kaustuv Banerjee, Sandipan Roy, Moumita Kotal, and Kumar Biradha
American Chemical Society (ACS)
Coordination polymeric (CP) materials are of interest due their versatile applications in various fields. CP-based materials have a great potential to act as multifunctional materials given their diversified nature. A series of CPs was found to exhibit a combination of luminescence, redox, and electron paramagnetic resonance (EPR) activities with potential for multifunctional materials. In particular, four new CPs of Cu(II) and Co(II) containing bis(N-pyridyl amide) (L) and dicarboxylates have been synthesized and characterized by single-crystal X-ray and other techniques. The CPs were found to exhibit two types of two-dimensional (2D)-networks and one each of one-dimensional (1D) and three-dimensional (3D) networks. Interestingly the 1D-coordination polymer contains a tubular network which is formed by linking CoL2 macrocycles by 1,3-benzene-dicarboxylate anions. In one of the 2D-layers, the Cu(II) center was found to form an interesting trimeric secondary building unit via bridging of carboxylates and S...

Multifunctional hybrid materials based on carbon nanotube chemically bonded to reduced graphene oxide
Moumita Kotal and Anil K. Bhowmick
American Chemical Society (ACS)
A novel chemical approach is explored to design three-dimensional porous network of reduced graphene oxide (GO)/multiwalled carbon nanotube (MWCNT) hybrid from reduced GO connected to MWCNT by sp2 carbons. The process involved simultaneous functionalization, reduction, and stitching of GO by p-phenylenediamine and subsequent diazotization followed by C–C coupling with MWCNT. For comparison, a physical mixture was also prepared. The resulting hybrids were characterized by infrared, Raman, UV–vis, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and scanning tunneling microscopy. The chemical hybrid was shown to exhibit good electrical conductivity (210.48 S m–1), promising specific capacitance (277 F g–1) even at high current density (10 A g–1), remarkable energy density (21.32 W h kg–1) especially at high power density (3.13 kW kg–1), outstanding cyclability (89%) even after 2000 cycles, and good dye adsorption capacity (245 mg g–1) for c...

Polyaniline-carbon nanofiber composite by a chemical grafting approach and its supercapacitor application
Moumita Kotal, Awalendra K. Thakur, and Anil K. Bhowmick
American Chemical Society (ACS)
Unlike conventional routes by van der Waals forces, a facile and novel approach using covalent bonding is established in the present work to synthesize polyaniline (PANI)-grafted carbon nanofiber (CNF) composites as promising supercapacitors. For this purpose, toluenediisocyanate was initially functionalized to carboxylated CNF via amidation followed by reaction with excess aniline to form a urea derivative and residual aniline, which was subsequently polymerized and grafted with a urea derivative. Amidation of CNF (TCNF) and, consequently, the grafting of PANI on TCNF were verified by IR, Raman, 1H NMR, X-ray photoelectron, and UV-visible spectroscopic methods, X-ray diffraction, and thermogravimetric analysis. Morphological analysis revealed uniform distribution of PANI on the surface of TCNF, indicating strong interaction between them. Electrochemical tests of the composite containing 6 wt % TCNF demonstrated efficient capacitance of ∼557 F g(-1) with a capacity retention of 86% of its initial capacitance even after 2000 charge-discharge cycles at a current density of 0.3 A g(-1), suggesting its superiority compared to the materials formed by van der Waals forces. The remarkably enhanced electrochemical performance showed the importance of the phenyl-substituted amide linkage in the development of a π-conjugated structure, which facilitated charge transfer and, consequently, made it attractive for efficient supercapacitors.

Recent advances on preparation, properties and applications of polyurethane nanocomposites

Preparation and properties of in-situ polymerized polyurethane/stearate intercalated layer double hydroxide nanocomposites
Moumita Kotal, Suneel Kumar Srivastava, Saraswathi Kesavapillai Manu, Aravind Kumar Saxena, and Kailash Nath Pandey
Wiley
The present work deals with the effect of stearate intercalated layered double hydroxide (St-LDH) loadings on the morphological, mechanical, thermal, adhesive and flame retardant properties of polyurethane (PU)/St-LDH nanocomposites prepared by the in situ polymerization method. X-ray diffraction and transmission electron microscopy studies confirmed that exfoliation takes place at 3 wt% loading followed by intercalation at higher filler loadings in the PU matrix. The exfoliated structure has been further verified by atomic force microscopy. The measurements of stress-strain, thermogravimetric analysis, dynamic mechanical analysis, lap shear strength and peel strength analysis showed that the nanocomposites containing 3 wt% St-LDH exhibit excellent improvement in tensile strength (ca 175%) and log storage modulus (ca 14%), while PU/St-LDH (5 wt%) possesses optimum improvement in glass transition temperature (ca 6 °C), lap shear strength (200%) and peel strength (130%) over neat PU. In addition, the gradual improvements in limiting oxygen index value with St-LDH loading indicated the higher effectiveness in providing better barrier properties as well as better flame retardant behavior. Copyright © 2012 Society of Chemical Industry

Synergistic effect of organomodification and isocyanate grafting of layered double hydroxide in reinforcing properties of polyurethane nanocomposites
Moumita Kotal and Suneel K. Srivastava
Royal Society of Chemistry (RSC)
The present work offers a novel approach for interlamellar surface modification of the hydroxyl groups of pristine and organomodified (dodecyl sulfate, DS and stearate, St) layered double hydroxides (LDHs) by grafting with isocyanate group of methylene diphenylene diisocyanate (MDI) and isophorone diisocyanate (IPDI). FTIR and 1H NMR studies confirm the grafting of MDI and IPDI with LDHs. This has been further supported by XRD studies, which show a substantial increase in the interlayer spacings of isocyanate grafted DS and St-LDHs. The extent of grafting (wt%) has also been estimated on the basis of the residue left in air atmosphere at 1000 °C in thermogravimetric analysis (TGA). The synergistic effect of organomodification and isocyanate grafting of layered double hydroxide in reinforcing the properties of the polyurethane (PU) nanocomposites has also been investigated and the findings have been compared with PU nanocomposites obtained by individually grafted as well as organomodified LDHs. TEM and AFM studies establish better homogeneous dispersion and exfoliation of MDI grafted St-LDH in PU matrix as compared to the other isocyanate grafted LDHs. Among all the LDHs/PU nanocomposites, 3 wt% loaded MDI-grafted-St-LDH/PU exhibits the maximum improvements in tensile strength (391%), thermal stability (26 °C) and glass transition temperature (11 °C) and significant synergistic effect of organomodification and isocyanate grafting of LDHs. The enhancement in the properties of all grafted organomodified LDHs/PU nanocomposites is attributed to their nanolevel dispersion and interfacial interaction with PU.

Fabrication of gold nanoparticle assembled polyurethane microsphere template in trypsin immobilization
Moumita Kotal, Suneel K. Srivastava, and Tapas K. Maiti
American Scientific Publishers
The separation, reusability and high catalytic activity of bioconjugate remain challenging task in proteins bound gold nanoparticles. A facile synthetic route for the fabrication of gold nanoparticle assembled polyurethane microsphere template and immobilization of trypsin on gold/polyurethane surface to form trypsin-nanogold-polyurethane bioconjugate was developed. The bioconjugate was characterized by X-ray diffraction, Field emission scanning electron microscopy, Transmission electron microscopy, UV-visible, Fourier transform infrared, Fluorescence and Circular dichroism spectroscopy. The catalytic studies confirmed retention of approximately 40% of its original activity even after eight consecutive reaction cycles. The bioconjugate is also very effective for its separation from the reaction medium and exhibited significant enhanced stability over a wide range of pH and temperature compared to free trypsin. These findings clearly demonstrate that trypsin immobilized gold nanoparticle assembled polyurethane microsphere acts as an excellent recyclable biocatalyst with enzyme-specific biocompatibility.

RECENT SCHOLAR PUBLICATIONS

Cathode materials for rechargeable lithium batteries: Recent progress and future prospects
M Kotal, S Jakhar, S Roy, HK Sharma
Journal of Energy Storage 47, 103534 2022

Electroionic Artificial Muscles: Metal–Organic Framework‐Derived Graphitic Nanoribbons Anchored on Graphene for Electroionic Artificial Muscles (Adv. Funct. Mater. 29/2020).
M Kotal, R Tabassian, S Roy, S Oh, IK Oh
Advanced Functional Materials 30 (29) 2020

Metal–organic framework‐derived graphitic nanoribbons anchored on graphene for electroionic artificial muscles
M Kotal, R Tabassian, S Roy, S Oh, IK Oh
Advanced Functional Materials 30 (29), 1910326 2020

Graphene-templated cobalt nanoparticle embedded nitrogen-doped carbon nanotubes for efficient visible-light photocatalysis
M Kotal, A Sharma, S Jakhar, V Mishra, S Roy, SC Sahoo, HK Sharma, ...
Crystal Growth & Design 20 (7), 4627-4639 2020

Mechanochemical synthesis of a new triptycene-based imine-linked covalent organic polymer for degradation of organic dye
K Preet, G Gupta, M Kotal, SK Kansal, DB Salunke, HK Sharma, ...
Crystal Growth & Design 19 (5), 2525-2530 2019

Collectively exhaustive electrodes based on covalent organic framework and antagonistic Co‐doping for electroactive ionic artificial muscles
S Roy, J Kim, M Kotal, R Tabassian, KJ Kim, IK Oh
Advanced Functional Materials 29 (17), 1900161 2019

Electroactive Artificial Muscles Based on Functionally Antagonistic Core–Shell Polymer Electrolyte Derived from PS‐b‐PSS Block Copolymer
VH Nguyen, J Kim, R Tabassian, M Kotal, K Jun, JH Oh, JM Son, ...
Advanced Science 6 (5), 1801196 2019

Collectively exhaustive electrode for electro-active ionic artificial muscles based on covalent organic framework and antagonistic co-doping
S Roy, J Kim, M Kotal, R Tabassian, KJ Kim, IK Oh
Advanced Materials 29 (17) 2019

Design and Synthesis of PS-b-PSS Block Copolymer Electrolyte for Electroactive Artificial Muscles
VH Nguyen, IK Oh, W Hwang, J Kim, R Tabassian, M Kotal, K Jun, J Oh, ...
BAMN 2019 2019

Molybdenum Disulfide Grown on Graphene as Electrodes for Ionic Artificial Muscles
VH Nguyen, W Hwang, J Kim, R Tabassian, M Kotal, J Oh, J Son, ...
BAMN 2019 2019

Highly Bendable Ionic Soft Actuator Based on Nitrogen‐Enriched 3D Hetero‐Nanostructure Electrode
M Kotal, J Kim, R Tabassian, S Roy, VH Nguyen, N Koratkar, IK Oh
Advanced Functional Materials 28 (34), 1802464 2018

Electro-ionic Artificial Muscles based on Three-dimensional Graphene Nanostructures
J Kim, SH Bae, M Kotal, IK Oh
2018 3rd International Conference on Composite Materials and Material 2018

Actuators: Functionally Antagonistic Hybrid Electrode with Hollow Tubular Graphene Mesh and Nitrogen‐Doped Crumpled Graphene for High‐Performance Ionic Soft Actuators (Adv
R Tabassian, J Kim, VH Nguyen, M Kotal, IK Oh
Advanced Functional Materials 28 (5), 1870033 2018

Functionally Antagonistic hybrid electrode with hollow tubular graphene mesh and nitrogen‐doped crumpled graphene for high‐performance ionic soft actuators
R Tabassian, J Kim, VH Nguyen, M Kotal, IK Oh
Advanced Functional Materials 28 (5), 1705714 2018

Artificial Muscles: Electroionic Antagonistic Muscles Based on Nitrogen‐Doped Carbons Derived from Poly (Triazine‐Triptycene)(Adv. Sci. 12/2017)
S Roy, J Kim, M Kotal, KJ Kim, IK Oh
Advanced Science 4 (12), 1770062 2017

Electroionic Antagonistic Muscles Based on Nitrogen‐Doped Carbons Derived from Poly (Triazine‐Triptycene)
S Roy, J Kim, M Kotal, KJ Kim, IK Oh
Advanced Science 4 (12), 1700410 2017

Soft but powerful artificial muscles based on 3D graphene–CNT–Ni heteronanostructures
J Kim, SH Bae, M Kotal, T Stalbaum, KJ Kim, IK Oh
Small 13 (31), 1701314 2017

Nanohole-structured, iron oxide-decorated and gelatin-functionalized graphene for high rate and high capacity Li-Ion anode
SH Lee, M Kotal, JH Oh, P Sennu, SH Park, YS Lee, IK Oh
Carbon 119, 355-364 2017

Self-assembly and morphological control of three-dimensional macroporous architectures built of two-dimensional materials
JE Kim, JH Oh, M Kotal, N Koratkar, IK Oh
Nano Today 14, 100-123 2017

Nanohole-Structured, Iron Oxide-Decorated and N-doped Heteronanostructure as Lithium Ion Battery Anode
SH Lee, M Kotal, JH Oh, IK Oh
Graphene2017 2017

MOST CITED SCHOLAR PUBLICATIONS

Polymer nanocomposites from modified clays: Recent advances and challenges
M Kotal, AK Bhowmick
Progress in Polymer Science 51, 127-187 2015
Citations: 689

Sulfur and Nitrogen Co‐Doped Graphene Electrodes for High‐Performance Ionic Artificial Muscles
M Kotal, J Kim, KJ Kim, IK Oh
Advanced Materials 28 (8), 1610-1615 2016
Citations: 198

Polyaniline–carbon nanofiber composite by a chemical grafting approach and its supercapacitor application
M Kotal, AK Thakur, AK Bhowmick
ACS Applied Materials & Interfaces 5 (17), 8374-8386 2013
Citations: 147

Cathode materials for rechargeable lithium batteries: Recent progress and future prospects
M Kotal, S Jakhar, S Roy, HK Sharma
Journal of Energy Storage 47, 103534 2022
Citations: 98

Thermoplastic polyurethane and nitrile butadiene rubber blends with layered double hydroxide nanocomposites by solution blending
M Kotal, SK Srivastava, AK Bhowmick
Polymer International 59 (1), 2-10 2010
Citations: 93

Self-assembly and morphological control of three-dimensional macroporous architectures built of two-dimensional materials
JE Kim, JH Oh, M Kotal, N Koratkar, IK Oh
Nano Today 14, 100-123 2017
Citations: 89

Multifunctional hybrid materials based on carbon nanotube chemically bonded to reduced graphene oxide
M Kotal, AK Bhowmick
The Journal of Physical Chemistry C 117 (48), 25865-25875 2013
Citations: 89

Soft but powerful artificial muscles based on 3D graphene–CNT–Ni heteronanostructures
J Kim, SH Bae, M Kotal, T Stalbaum, KJ Kim, IK Oh
Small 13 (31), 1701314 2017
Citations: 87

Enhancements in conductivity and thermal stabilities of polypyrrole/polyurethane nanoblends
M Kotal, SK Srivastava, B Paramanik
The Journal of Physical Chemistry C 115 (5), 1496-1505 2011
Citations: 75

Sulfur and nitrogen co-doped holey graphene aerogel for structurally resilient solid-state supercapacitors under high compressions
M Kotal, H Kim, S Roy, IK Oh
Journal of Materials Chemistry A 5 (33), 17253-17266 2017
Citations: 74

Functionalized graphene with polymer as unique strategy in tailoring the properties of bromobutyl rubber nanocomposites
M Kotal, SS Banerjee, AK Bhowmick
Polymer 82, 121-132 2016
Citations: 74

Synthesis and characterization of polyurethane/Mg‐Al layered double hydroxide nanocomposites
M Kotal, T Kuila, SK Srivastava, AK Bhowmick
Journal of Applied Polymer Science 114 (5), 2691-2699 2009
Citations: 73

Defect engineering route to boron nitride quantum dots and edge-hydroxylated functionalization for bio-imaging
JH Jung, M Kotal, MH Jang, J Lee, YH Cho, WJ Kim, IK Oh
RSC Advances 6 (77), 73939-73946 2016
Citations: 51

Recent progress in multifunctional graphene aerogels
M Kotal, J Kim, J Oh, IK Oh
Frontiers in Materials 3, 29 2016
Citations: 46