Dhrubajyoti Bhattacharjya

• Doctor of Philosophy
• Scientist at RISE Research Institutes of Sweden

The development of rechargeable lithium-ion battery (LIB) technology has facilitated the shift toward electric vehicles and grid storage solutions. This technology is currently undergoing significant development to meet industrial applications for portable electronics and provide our society with “greener” electricity. The large increase in LIB pro...

The subbituminous type of coal is considered low-grade and unsuitable for power generation due to its low calorific value and high impurity content. As a result, this type of coal does not have any economic value and so is mostly lying unutilized. In this work, we have explored a simple and easily scalable approach to converting this low-grade subb...

Currently, tremendous efforts have been made to obtain a single efficient energy storage device with both high energy and power density, bridging the gap between supercapacitors and batteries where the challenges are on combination of various types of materials in the devices. Supercapacitor-battery hybrid (SBH) energy storage devices, having excel...

In the last decade, there has been a phenomenal development in the commercially viable, large-scale synthesis of graphene, a multifunctional advanced carbon nanomaterial, which is gaining popularity for its diverse range of applications, especially in energy storage, composites, sensors, and membranes. With the increasing demand, a large number of...

Due to the dual advantage of capacitive and faradaic charge storage mechanisms, Li-ion capacitors (LICs) are regarded as promising energy storage technology for many high-power applications. However, the high cost and intricacy of indispensable pre-lithiation step in LIC fabrication are the major stumbling block against its widespread commercial in...

Affordable and clean energy is one of the major sustainable development goals that can transform our world. Currently, researchers are focusing on cheap carbon electrode materials to develop energy storage devices, including high energy density supercapacitors and Li-ion batteries. In this review article, the prime focus has been given on different...

Lithium ion capacitors (LICs) are foreseen to be a complementary alternative of vital importance to current energy storage issues, coupling high energy density delivered by batteries with high power/long cycle life offered by supercapacitors. The prime issues in realising this technology are pre-lithiation and replacement of graphite electrodes tha...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Most lithium-ion capacitor (LIC) devices include graphite or non-porous hard carbon as negative electrode often failing when demanding high energy at high power densities. Herein, we introduce a new LIC formed by the assembly of polymer derived hollow carbon spheres (HCS) and a superactivated carbon (AC), as negative and positive electrodes, respec...

Metal ion capacitors (MICs) are foreseen to be a complementary alternative of vital importance to current energy storage issues, coupling high energy density delivered by batteries with high power/long cycle life offered by supercapacitors. The prime issues in realising this technology are pre-metallation and replacement of graphite electrodes that...

Laboratory testing of supercapacitor cells are generally performed in Swagelok or coin cell setup, where two small electrodes and electrolyte-saturated separators are placed in tightly packed cell assembly. However, more often the performances achieved in laboratory testing are failed to replicate in larger commercially viable cells due to differen...

Herein we investigate the performance of an aqueous asymmetric supercapacitor (AAS) assembled using a novel nanostructured NiCo2O4 as positive electrode and a polymer derived superactivated carbon (SAC) as negative electrode. The combination of both the nanostructured NiCo2O4 and the carbon with hierarchical porosity and ultrahigh specific surface...

Direct reduction of graphene oxide has been regarded as the economically viable route for large-scale synthesis of graphene. However, the currently known methods suffer from either poor reduction efficiency or involve multi-step and energy-intensive reduction processes. Here, we demonstrate a remarkably fast, single step as well as highly efficient...

Nanostructured carbon having nitrogen as heteroatom was synthesized from waste tea, a cheap and abundant waste generated around the world. The synthesis process is simple, environmental being one-step pyrolysis in inert atmosphere. The carbon synthesized at 800°C (WTC-800) has mesh like morphology with abundantmesopores. The BET analysis reveals me...

In the race of gaining higher energy density, carbon's capacity to retain power density is generally lost due to defect incorporation and resistance increment in carbon electrode. Herein, a relationship between charge carrier density/charge movement and supercapacitance performance is established. For this purpose we have incorporated the most defe...

Ternary spinal NiCo2O4 nanostructure holds great promise as high-performance anode material for next generation Li-ion batteries because of its higher electrical conductivity and electrochemical activity. In this work, two-dimensional hexagonal NiCo2O4 nanoplates are synthesized by a simple and cost-effective template-free method through co-precipi...

Agarose has been functionalized (acetylated/carbanilated) in an ionic liquid (IL) medium of 1-butyl-3-methylimidazolium acetate at ambient conditions. The acetylated agarose showed a highly hydrophobic nature, whereas the carbanilated agarose could be dissolved in water as well as in the IL medium. Thermoreversible ionogels were obtained by cooling...

Ternary spinel NiCo2S4 nanorods are tested for the first time as anode electrode for Li ion battery. When the electrode is fabricated using carboxymethyl cellulose-polyacryl amide composite binder, it is found to restrict or suppress the formation of polymeric gel passivation layer. As a result, the electrode not only delivers excellent specific ca...

Heteroatom and porosity both have different, but definite effect on the electrochemical capacitance of carbon materials. These effects are studied in details by cubic ordered mesoporous carbons (OMCs) co-doped with N and P. 3-dimentional (3D) mesoporous silica, KIT-6 with bicontinuous cubic Ia3d symmetry is utilized as a hard template to synthesize...

Nitrogen-doped ordered mesoporous carbons (N-OMCs) with different morphologies are prepared as oxygen reduction reaction (ORR) catalysts through pyrolysis of iron phthalocyanine-infiltrated SBA-15 silica with different mesochannel lengths. Excellent ORR activity with a nearly four-electron transfer process is observed in both alkaline and acidic me...

In recent years, graphene-based materials have been in forefront as electrode material for electro-chemical energy generation and storage. In spite of this prevalent interest, synthesis procedures have not attained three important efficiency requirements, i.e. cost, energy and eco-friendliness. In this regard, in the present work, graphene nanoplat...

Solvent or reaction medium always plays a lead role in synthesis chemistry. Glycerol has been studied as a green solvent for different organic transformations and is also expected to give interesting control in material synthesis. In this study, we use aqueous glycerol to synthesize zinc glycerolate and corresponding ZnO micro-flower structures wit...

Cow dung, one of the most abundant biological wastes on earth is used for the synthesis of activated carbon by employing KOH as activating agent. Combined effect of inorganic salts and silica, which are inherently present in cow dung and external KOH activation helps to create abundant micropores and mesopores. The resultant activated carbon, when...

A unique and novel soft template-based hydrothermal approach was developed for the synthesis of hollow TiO2 and hollow TiO2@N-doped carbon. The synthesis strategy involves the slow hydrolysis of hexamethylenetetramine (HMTA) at 100 °C in the presence of a block copolymer (Pluronic F127) as the surfactant, resorcinol as the polymer precursor and tit...

A simple, efficient and scalable approach is developed for synthesis of Vulcan XC-72(carbon)-supported Pt nanoparticles (NPs) that combines homogeneous deposition (HD) of Pt complex species through reaction with OH- ions generated by in situ hydrolysis of urea and subsequent reduction by reducing species generated from radiolysis of water by γ-rays...

Porous α-Fe2O3 nanorods are successfully synthesized without any templates by a simple wet chemical synthesis method using ferrous sulphate (FeSO4·7H2O) and sodium acetate (CH3COONa) as starting materials. In this method, initially obtained α-FeOOH is calcinated at 300 °C for 2 h to form 1-dimensional porous α-Fe2O3 nanorods. Thermogravimetric anal...

Nitrogen-doped turbostratic carbon nanoparticles (NPs) are prepared using fast single-step flame synthesis by directly burning acetonitrile in air atmosphere and investigated as an anode material for lithium ion batteries. The as-prepared N-doped carbon NPs show excellent Li-ion stoarage properties with initial discharge capacity of 596 mA h g-1 wh...

Rod-shaped ordered mesoporous carbons (OMCs) with different lengths, prepared by replication method using the corresponding size-tunable SBA-15 silicas with the same rodlike morphology as templates, are explored as anode material for Li-ion battery. All of the as-synthesized OMCs exhibit much higher Li storage capacity and better cyclability along...

Phosphorus-doped ordered mesoporous carbons (POMCs) with different lengths were synthesized using a metal-free nanocasting method of SBA-15 mesoporous silica with different sizes as template and triphenylphosphine and phenol as phosphorus and carbon sources, respectively. The resultant POMC with a small amount of P doping is demonstrated as a metal...

Polyaniline (PANI) in fractal dimension has been electrodeposited reproducibly on highly oriented pyrolytic graphite (HOPG) from 0.2 M aniline in 1 M aqueous HCl solution by potentiodynamic sweeping in the range of -0.2 to 0.76 V vs Ag/AgCl at room temperature. Fractal growth of PANI dendrimers is affected by diffusion limited polymerization (DLP)...

Non isothermal decomposition of synthetically prepared hydromagnesite phase with two different morphologies (2-D micro sheets and nests) was studied in dynamic nitrogen atmosphere by thermogravimetric analysis, differential thermogravimetric analysis, and differential scanning calorimetric techniques. Two different kinetic models, i.e. the Friedman...

Rectangular hydromagnesite microsheet is prepared by simple solution route through controlled hydrolysis-condensation of magnesium chloride in urea solution using ethylene glycol (EG) as a bifunctional cosolvent. Calcination of the hydromagnesite sheets at 450°C produces MgO without any alteration in the morphology. The MgO sheets were of 2–3μ side...

Study o Ferromagnetic shape memory alloys (FSMAs) is an interesting topic of present day research because of their large magnetic field induced shape recovery. They are important materials for the development of sensors and actuator based applications. Attempt for miniaturization of these actuators and sensors have led to the study of thin films. B...