Mesoporous carbon nanofiber engineered for improved supercapacitor performance

Ghosh, Subrata,Yong, Wan Dao,Jin, En Mei,Polaki, Shyamal Rao,Jeong, Sang Mun,Jun, Hangbae Springer-Verlag 2019 Korean Journal of Chemical Engineering Vol.36 No.2

A review on metal nitrides/oxynitrides as an emerging supercapacitor electrode beyond oxide

Subrata Ghosh,정상문,Shyamal Rao Polaki 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.7

Electrode materials design is the most significant aspect in constructing a supercapacitor device. The evolution of metal nitrides/oxynitrides as supercapacitor electrode is strikingly noticeable today besides prevailing carbon or 2D materials, metal oxides/hydroxides and conducting polymers electrode materials. The theoretically estimated specific capacitance of a nitride-based supercapacitor is 1,560 F g1. These nanostructures exhibit an excellent capacitive behavior with a specific capacitance of 15-951.3mF cm2 or 82-990 F g1, high energy density (16.5-162Wh Kg1) and power density (7.3-54,000W Kg1). On this account, supercapacitor performance of metal nitrides/oxynitrides is reviewed exclusively. The major focus of the present review is directed towards state-of-art progress in supercapacitor performance of nitrides/oxynitrides, underlying charge-storage mechanism, important outcomes and their limitations. Finally, we conclude with challenges and prospects of metal nitrides/oxynitrides for supercapacitor electrodes.

The spatial clustering of dengue disease and risk susceptibility mapping: an approach towards sustainable health management in Kharagpur city, India

Subrata Ghosh,Santanu Dinda,Nilanjana Das Chatterjee,Kousik Das,Riya Mahata 대한공간정보학회 2019 Spatial Information Research Vol.27 No.2

Dengue fever becomes one of the serious vectorborne diseases in the world, particularly in tropical countries. Mosquitoes borne disease transmission are mainly transpired by physical, environmental and socio-economic variables. Therefore, disease mapping is essential for monitoring, prediction, and prevention of dengue. Accordingly, the aims of this research are to find out the dengue outbreak, spatial pattern, understand the factors and construct a risk map to accurately predict and control of dengue. For this purpose, the Kharagpur city of West Bengal has been selected which is frequently encountered with the dengue outbreak. Epidemiological data were collected from the district health department. The spatial scan statistics of the Poisson model and Local Moran’s I is used for the mapping of spatial patterns and concentration of dengue and Monte Carlo hypothesis testing was applied to test the significance of the result. Therefore, multiple logistic regression analysis has been applied with selected parameters to produce a risk map for the entire study area. Finally, this study has proposed suitable site-specific management strategies. However, this study provides an example of disease risk estimation which will be remarkable for spatial analysis of epidemiological research as well as health planning and disease surveillance.

Analyzing risk factors for shrinkage and transformation of East Kolkata Wetland, India

Subrata Ghosh,Santanu Dinda,Nilanjana Das Chatterjee,Kousik Das 대한공간정보학회 2018 Spatial Information Research Vol.26 No.6

The East Kolkata Wetland, called the ‘kidney’ of city Kolkata has now become a significant issue for its gradual loss and modification of anthropogenic activities. A socioeconomic elucidation had been used in this article through the analysis using GIS and field observation. Changes of wetland area have been determined from 1991 to 2017 with Landsat images and accuracy assessment through ground truth verification. It is seen that loss of wetland from 1991 to 2001 was 23.55% where it was 7.34% in 2011 to 2017, mainly due to the result of land transformation for aquaculture activity. Hence, three phases of degradation have been observed in this study, these are: the phase of rapid degradation, the phase of controlled degradation and phase of transforming degraded. At the same time, it’s highlighted the loophole of management actions. A multi-criteria analysis technique with the analytic hierarchy process has been applied to determine the risk factors of wetland degradation and it is seen that expansion of built-up area, encroachment of cropland, the transformation of wetland into fishing ponds are responsible for wetland degradation. In the conclusion, it highlights the approaches of land developers and real estate agents in their wetland hunting process and emergence consequences on the environment as well as conserving approaches for sustainable management.

Plasma-electric field controlled growth of oriented graphene for energy storage applications

Ghosh, Subrata,Polaki, S R,Kamruddin, M,Jeong, Sang Mun,Ostrikov, Kostya (Ken) IOP 2018 Journal of Physics. D, Applied Physics Vol.51 No.14

<P>It is well known that graphene grows as flat sheets aligned with the growth substrate. Oriented graphene structures typically normal to the substrate have recently attracted major attention. Most often, the normal orientation is achieved in a plasma-assisted growth and is believed to be due to the plasma-induced <I>in-built</I> electric field, which is usually oriented normal to the substrate. This work focuses on the effect of an <I>in-built</I> electric field on the growth direction, morphology, interconnectedness, structural properties and also the supercapacitor performance of various configurations of graphene structures and reveals the unique dependence of these features on the electric field orientation. It is shown that tilting of growth substrates from parallel to the normal direction with respect to the direction of <I>in-built</I> plasma electric field leads to the morphological transitions from horizontal graphene layers, to oriented individual graphene sheets and then interconnected 3D networks of oriented graphene sheets. The revealed transition of the growth orientation leads to a change in structural properties, wetting nature, types of defect in graphitic structures and also affects their charge storage capacity when used as supercapacitor electrodes. This simple and versatile approach opens new opportunities for the production of potentially large batches of differently oriented and structured graphene sheets in one production run.</P>

Designing metal oxide-vertical graphene nanosheets structures for 2.6V aqueous asymmetric electrochemical capacitor

Ghosh, Subrata,Polaki, S.R.,Sahoo, Gopinath,Jin, En-Mei,Kamruddin, M.,Cho, Jung Sang,Jeong, Sang Mun Elsevier 2019 Journal of industrial and engineering chemistry Vol.72 No.-

<P><B>Abstract</B></P> <P>The asymmetric electrochemical capacitor was realized by MnO<SUB>2</SUB>/Vertical graphene nanosheets (VGN) and Fe<SUB>2</SUB>O<SUB>3</SUB>/VGN as positive and negative electrodes, respectively. The surface of VGN skeleton is independently decorated with MnO<SUB>2</SUB> having sponge gourd-like morphology and Fe<SUB>2</SUB>O<SUB>3</SUB> having nanorice like morphology. Both the electrodes have shown around 250 times higher charge-storage capacity than the bare VGN (0.47mF/cm<SUP>2</SUP>) with the specific capacitance of 118 (MnO<SUB>2</SUB>/VGN) and 151mF/cm<SUP>2</SUP> (Fe<SUB>2</SUB>O<SUB>3</SUB>/VGN). The fabricated asymmetric device exhibited a specific capacitance of 76mF/cm<SUP>2</SUP> and energy density of 71μWh/cm<SUP>2</SUP> with an excellent electrochemical stability up to 12,000 cycles, over a potential window of 2.6V.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Metal oxide-vertical graphene electrodes were prepared. </LI> <LI> Metal oxide-vertical graphene nanoshees structure was found to be super-hydrophilic. </LI> <LI> A plausible formation mechanism of metal oxides on the surface of vertical graphene is propsed. </LI> <LI> As fabricated asymmetric supercapacitor device was operated in an extended window of 2.6V. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Designing metal oxide-vertical graphene nanosheets structures for 2.6 V aqueous asymmetric electrochemical capacitor

Subrata Ghosh,S.R. Polaki,Gopinath Sahoo,En Mei Jin,M. Kamruddin,조정상,정상문 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.72 No.-

The asymmetric electrochemical capacitor was realized by MnO2/Vertical graphene nanosheets (VGN)and Fe2O3/VGN as positive and negative electrodes, respectively. The surface of VGN skeleton isindependently decorated with MnO2 having sponge gourd-like morphology and Fe2O3 having nanoricelike morphology. Both the electrodes have shown around 250 times higher charge-storage capacity thanthe bare VGN (0.47 mF/cm2) with the specific capacitance of 118 (MnO2/VGN) and 151 mF/cm2 (Fe2O3/VGN). The fabricated asymmetric device exhibited a specific capacitance of 76 mF/cm2 and energydensity of 71 mWh/cm2 with an excellent electrochemical stability up to 12,000 cycles, over a potentialwindow of 2.6 V.

Ethnobotanical perspectives of Bakhar: an indigenous starter culture used to prepare traditionally fermented rice beverage in rural West Bengal, India

Ghosh Sudipta,Sen Sukanta K.,Mondal Subrata 한국식품연구원 2022 Journal of Ethnic Foods Vol.9 No.-

Haria, a fermented rice beverage, is commonly consumed as a traditional drink by the tribal people of rural West Bengal. This beverage is prepared by fermenting steamed rice with the starter culture tablets, known as Bakhar. It is known that some plant parts are added during Bakhar preparation that confer certain ethnomedicinal properties to the beverage as well as to Bakhar itself. An ethnobotanical survey was conducted that allowed documenting the traditional knowledge regarding this ethnic beverage preparation and it reveals that 10 plant species and one lichen species are used by the Santal tribe to prepare the Bakhar. Among them, roots of Kedar, Chaoli, rhizome of Bach, and bark of Lodh plants are essential, while other plant parts are used due to their specifc taste, favor, and therapeutic properties. But nowadays little or no plant additives are used during commercial Haria preparation for cost-efectiveness. Homemade and commercially produced Haria were investigated for their nutritional quality which revealed that homemade beverage contains more bioactive compounds, such as ascorbic acid (15.40 mg/100 ml) and favonoids (36.67 mg/100 ml), which contribute toward the antioxidant property of the beverage. This current study documents the important medicinal plants used in the starter culture, the detailed process of Bakhar and Haria preparation, and the nutritional quality of Haria highlighting its ethnomedicinal properties.

Multi-channel-contained few-layered MoSe2 nanosheet/N-doped carbon hybrid nanofibers prepared using diethylenetriamine as anodes for high-performance sodium-ion batteries

정선영,Subrata Ghosh,김재광,강동원,정상문,강윤찬,조정상 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.75 No.-

A facile new strategy for the synthesis of multi-channel-contained N-doped carbon nanofibers composedof few-layered MoSe2 nanosheets (denoted as MC-NCNF/MoSe2) was introduced and the composite wasdemonstrated as an anode material for sodium-ion batteries. This was thefirst time that diethylenetri-amine was introduced as a pore generator in the electrospinning process and played a key role ingenerating multi-channels in the structure by phase-separation from the molybdenum salt andsubsequent volatilization without any additional process. Polyvinylpyrrolidone was used as a carbonprecursor and played the role of a N-doping source for the carbon matrix. MC-NCNF/MoSe2 achieved ahigh reversible discharge capacity of 386 mA h g 1 at a current density of 0.5 A g 1 after the 300th cycleand superior rate capability of 285 mA h g-1 at 10.0 A g 1. The multi-channeled structure of MC-NCNF/MoSe2 facilitated effective Na+ and electron diffusion during repeated discharge/charge processes andaccommodated the huge volume expansion of the MoSe2 nanosheets induced by electrochemicalreaction of the Na+ ion.

An analysis of transport suitability, modal choice and trip pattern using accessibility and network approach: a study of Jamshedpur city, India

Santanu Dinda,Subrata Ghosh,Nilanjana Das Chatterjee 대한공간정보학회 2019 Spatial Information Research Vol.27 No.2

The transportation system is considered the most important element of urban infrastructure and therefore, contemporary urban research precise more emphasis on the well-managed sustainable transport system. Accessibility and connectivity are two important tools regarding urban mobility, trip generation and modal choice as well as transportation management. The assessment of transport suitability is now the central part of transport management. From these perspectives, this study has been focused on the patterns of urban mobility and modal choice on the basis of transport accessibility and suitability. The Jamshedpur city and five adjoining urban areas are selected for assessment. The GIS-based accessibility modeling and network analysis have been used in this study. Moreover, the empirical field survey has also been made for the assessment of trip generation in selected nodes. Therefore, the analytic hierarchy process (AHP) was applied to assess the nature and patterns of trip occurrences and content validity ratio (CVR) and consistency ratio (CR) were used for validation. Furthermore, transport suitability index (TSI) in the different traffic zones were measured. The result shows that Jamshedpur is the most suitable in existing transportation supply–demand system as well as sustainable transportation management.