Susanta Sinha Mahapatra - Academia.edu (original) (raw)
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Papers by Susanta Sinha Mahapatra
Journal of Materials Chemistry A
This review provides a comprehensive overview of various advanced modification strategies of meta... more This review provides a comprehensive overview of various advanced modification strategies of metal-sulfide based nanomaterials for electrochemical CO2 reduction to valuable products.
Journal of the Indian Chemical Society
Ruthenium(III} catalyses the title reaction in the concentration range of 10-2 ppm and the reacti... more Ruthenium(III} catalyses the title reaction in the concentration range of 10-2 ppm and the reaction rate bears a first order dependence on the catalyst concentration under the experimental conditions, [dimethyl sulphoxideJ » [cerium(IV)] ») [ruthenium(IJI)] in 1.0 mol dm=". suiph uric acid media. From the measurement of rate ofthe process which is first order with respect to cerium(IV)
Fullerenes, Nanotubes and Carbon Nanostructures
Journal of Applied Electrochemistry
Hydrogen evolution reaction (HER) is of high priority at present. Existing research has involved ... more Hydrogen evolution reaction (HER) is of high priority at present. Existing research has involved the use of noble metals as catalysts for HER, thus putting an urgency to develop low-cost materials to replace them. In this work, metal-free Oleic acid functionalized Carbon Dots have been for the first time reported to have outstanding activity for HER. Electrochemical investigation reveals excellent catalytic performance with overpotential of 1 mV at a current density of-5 mA cm −2. The performance at this range marks a significant milestone and paves the way for a sustainable future of metal-free catalysis.
Nanotechnology, 2018
Nanostructured poly(m-aminophenol) (PmAP) coated freestanding carbon nanofiber (CNF) mats were fa... more Nanostructured poly(m-aminophenol) (PmAP) coated freestanding carbon nanofiber (CNF) mats were fabricated through simple in situ rapid-mixing polymerization of m-aminophenol in the presence of a CNF mat for flexible solid-state supercapacitors. The surface compositions, morphology and pore structure of the hybrid mats were characterized by using various techniques, e.g., FTIR, Raman, XRD, FE-SEM, TEM, and N2 absorption. The results show that the PmAP nanoparticles were homogeneously deposited on CNF surfaces and formed a thin flexible hybrid mat, which were directly used to made electrodes for electrochemical analysis without using any binders or conductive additives. The electrochemical performances of the hybrid mats were easily tailored by varying the PmAP loading on a hybrid electrode. The PmAP/CNF-10 hybrid electrode with a relatively low PmAP loading (> 42 wt%) showed a high specific capacitance of 325.8 F g-1 and a volumetric capacitance of 273.6 F cm-3 at a current density of 0.5 A g-1, together with a specific capacitance retention of 196.2 F g-1 at 20 A g-1. The PmAP/CNF-10 hybrid electrode showed good cycling stability with 88.2% capacitance retention after 5000 cycles. A maximum energy density of 45.2 Wh kg-1 and power density of 20.4 kW kg-1 were achieved for the PmAP/CNF-10 hybrid electrode. This facile and cost-effective synthesis of a flexible binder-free PmAP/CNF hybrid mat with excellent capacitive performances encourages its possible commercial exploitation.
ACS Sustainable Chemistry & Engineering, 2017
Freestanding nitrogen-doped porous carbon nanofibres (NCNFs) mats were prepared by electrospinnin... more Freestanding nitrogen-doped porous carbon nanofibres (NCNFs) mats were prepared by electrospinning of polyacrylonitrile/poly(m-aminophenol) (PAN/PmAP) precursor blends with different polymeric compositions followed by thermal stabilization and carbonization. The morphology, pore structure and surface elemental compositions of as-prepared NCNFs were characterized by different techniques such as scanning electron microscopy, transmission electron microscopy, N 2 adsorption, Raman spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The charge-storage capability of the fabricated NCNFs was investigated in KOH electrolyte. The electrochemical performances of NCNFs were evaluated by varying the PmAP loading in the blend compositions. The highest specific capacitance of 347.5 F g-1 at 0.5 mA cm-2 together with a capacitance retention of 173.2 F g-1 at 20 mA cm-2 was achieved for the PAN:PmAP (85:15 w/w) NCNFs (NCNF 85:15). The volumetric capacitance of 200.8 F cm-3 at 0.5 mA cm-2 was recorded for the NCNF 85:15. The NCNF 85:15 showed the maximum energy density of 12.1 Wh kg-1 at 0.093 kW kg-1 and good cycling stability with 90.5% capacitance retention after 10000 cycles. The excellent capacitive performances of the NCNF 85:15 was attributed to high effective surface area, high content of mesoporosity, good conducvity and high fraction of hetero-atom doped carbon, which result in both electrochemical double layer and Faradaic capacitance contributions.
Journal of Power Sources, 2004
One of the key points to develop a cost-effective direct alcohol fuel cell (DAFC) is to investiga... more One of the key points to develop a cost-effective direct alcohol fuel cell (DAFC) is to investigate cheaper electrocatalysts for the oxidation of alcohol at the anode, allowing an increase in the current density and a decrease in the anodic overvoltage. In this respect, polycrystalline deposits of platinum and platinum-ruthenium on a CuNi (70:30) alloy support are investigated here. Electro-oxidation of ethanol in 0.5 M NaOH is studied over these electrodes. Cyclic voltammetry, steady state polarization and electrochemical impedance spectroscopy are used to investigate the kinetics and mechanism of ethanol electro-oxidation. Efforts are also made to correlate the catalytic activity of such electrodes with their surface morphology.
International Journal of Hydrogen Energy, 2011
Electrochimica Acta, 2010
Ethanol has been recognized as the ideal fuel for direct alcohol fuel cell (DAFC) systems due to ... more Ethanol has been recognized as the ideal fuel for direct alcohol fuel cell (DAFC) systems due to its high energy density, non-toxicity and its bio-generation. However the complete conversion of ethanol to CO 2 is still met with challenges, due to dearth of suitable catalysts for the electro-oxidation. In the present work the effect of temperature on the catalytic oxidation of ethanol in alkaline medium over electrodeposited Pt and Pt-Pd alloyed nano particles on carbon support and also on the product formation during the course of reaction have been studied within the temperature range of 20-80 • C. The information on surface morphology, structural characteristics and bulk composition of the catalyst was obtained using SEM, XRD and EDX. BET surface area and pore widths of the catalyst particles were calculated by applying the BET equation to the adsorption isotherms. The electrochemical techniques like cyclic voltammetry, chronoamperometry and impedance spectroscopy were employed to investigate the electrochemical parameters related to electro-oxidation of ethanol in alkaline pH on the catalyst surfaces under the influence of temperature. The results show that the oxidation kinetics of ethanol on the alloyed Pt-Pd/C catalysts is significantly improved compared to that on Pt alone. The observations were interpreted in terms of the synergistic effect of higher electrochemical surface area, preferred OH − adsorption on the surface and the ad-atom contribution of the alloyed matrix. A pronounced influence of temperature on the reaction kinetics was manifested in the diminution of charge transfer resistance and activation energy of the ethanol oxidation with Pd incorporation into the Pt matrix, ensuring greater tolerance of the alloyed catalyst towards ethanolic residues. The higher yield of the reaction products like acetate and CO 3 −2 on the alloyed catalyst compared to Pt alone in alkaline medium, as estimated by ion chromatography, further substantiates the catalytic superiority of the Pt-Pd/C catalyst over Pt/C.
International Journal of Hydrogen Energy, 2011
In the present investigation, Vulcan XC-72 supported Pt and Pt based binary and ternary catalysts... more In the present investigation, Vulcan XC-72 supported Pt and Pt based binary and ternary catalysts (Pt/C, PtPd/C, PtAu/C, PtPdAu/C) have been synthesized under borohydride reduction scheme and applied for the study of the electro-oxidation of ethanol in alkaline media at room temperature. The surface morphology of the catalysts was determined by XRD (X-ray diffraction) & TEM (transmission electron microscopy) analysis. XRD patterns reveal that all the catalysts have disordered face center cubic lattice structures. Low resolution TEM images reveal uniform dispersion of metal nano particles on carbon support having an average size of 3e4.5 nm. HRTEM is also carried out for the determination of the distance between the lattice planes. Different textural properties including external surface area, pore volume and widths of the catalyst matrix were calculated by applying the BET equation to the adsorption isotherms. During electrolysis substantial increase in anodic peak current was observed for ethanol oxidations when the second and third metal component was introduced into the Pt matrix as in case of PtPdAu/C catalysts. The charge transfer resistance (R ct) for ethanol oxidation was substantially reduced from 87.9 U on Pt/C to 7.74 U on PtPdAu/C demonstrating the superior electrode kinetics behavior of the latter over the other catalysts studied. Thus Au and Pd incorporation into the Pt matrix not only increases the catalytic efficiency of the alloyed catalyst but at the same time effectively reduces the Pt content in the ternary system.
Background: Chromophobe renal cell carcinoma (ChRCC) is the second common subtype of non-clear ce... more Background: Chromophobe renal cell carcinoma (ChRCC) is the second common subtype of non-clear cell renal cell carcinoma (nccRCC), which accounting for 4-5% of renal cell carcinoma (RCC). However, there is no effective biomarker to predict clinical outcomes of this malignant disease. Bioinformatic methods may provide a feasible potential to solve this problem. Methods: In this study, differentially expressed genes (DEGs) of ChRCC samples on The Cancer Genome Atlas database were filtered out to construct co-expression modules by weighted gene co-expression network analysis and the key module were identified by calculating module-trait correlations. Functional analysis was performed on the key module and candidate hub genes were screened out by co-expression and MCODE analysis. Afterwards, real hub genes were filter out in an independent dataset GSE15641 and validated by survival analysis. Results: Overall 2215 DEGs were screened out to construct eight co-expression modules. Brown module was identified as the key module for the highest correlations with pathologic stage, neoplasm status and survival status. 29 candidate hub genes were identified. GO and KEGG analysis demonstrated most candidate genes were enriched in mitotic cell cycle. Three real hub genes (SKA1, ERCC6L, GTSE-1) were selected out after mapping candidate genes to GSE15641 and two of them (SKA1, ERCC6L) were significantly related to overall survivals of ChRCC patients. Conclusions: In summary, our findings identified molecular markers correlated with progression and prognosis of ChRCC, which might provide new implications for improving risk evaluation, therapeutic intervention, and prognosis prediction in ChRCC patients.
Materials Characterization, 2009
Electropolymerization of aniline at the graphite electrodes was achieved by potentiodynamic metho... more Electropolymerization of aniline at the graphite electrodes was achieved by potentiodynamic method. Electrodeposition of Pd (C-PANI-Pd) and Ni (C-PANI-Ni) and codeposition of Pd-Ni (C-PANI-Pd-Ni) microparticles into the polyaniline (PANI) film coated graphite (C-PANI) were carried out under galvanostatic control. The morphology and composition of the composite electrodes were obtained using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) techniques. The electrochemical behavior and electrocatalytic activity of the electrode were characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometric (CA) methods in acidic medium. The C-PANI-Pd-Ni electrode showed an improved catalytic performance towards methanol oxidation in terms of lower onset potential, higher anodic oxidation current, greater stability, lower activation energy, and lower charge transfer resistance. The enhanced electrocatalytic activity might be due to the greater permeability of C-PANI films for methanol molecules, better dispersion of Pd-Ni microparticles into the polymer matrixes, and the synergistic effects between the dispersed metal particles and their matrixes.
Journal of Materials Chemistry A
This review provides a comprehensive overview of various advanced modification strategies of meta... more This review provides a comprehensive overview of various advanced modification strategies of metal-sulfide based nanomaterials for electrochemical CO2 reduction to valuable products.
Journal of the Indian Chemical Society
Ruthenium(III} catalyses the title reaction in the concentration range of 10-2 ppm and the reacti... more Ruthenium(III} catalyses the title reaction in the concentration range of 10-2 ppm and the reaction rate bears a first order dependence on the catalyst concentration under the experimental conditions, [dimethyl sulphoxideJ » [cerium(IV)] ») [ruthenium(IJI)] in 1.0 mol dm=". suiph uric acid media. From the measurement of rate ofthe process which is first order with respect to cerium(IV)
Fullerenes, Nanotubes and Carbon Nanostructures
Journal of Applied Electrochemistry
Hydrogen evolution reaction (HER) is of high priority at present. Existing research has involved ... more Hydrogen evolution reaction (HER) is of high priority at present. Existing research has involved the use of noble metals as catalysts for HER, thus putting an urgency to develop low-cost materials to replace them. In this work, metal-free Oleic acid functionalized Carbon Dots have been for the first time reported to have outstanding activity for HER. Electrochemical investigation reveals excellent catalytic performance with overpotential of 1 mV at a current density of-5 mA cm −2. The performance at this range marks a significant milestone and paves the way for a sustainable future of metal-free catalysis.
Nanotechnology, 2018
Nanostructured poly(m-aminophenol) (PmAP) coated freestanding carbon nanofiber (CNF) mats were fa... more Nanostructured poly(m-aminophenol) (PmAP) coated freestanding carbon nanofiber (CNF) mats were fabricated through simple in situ rapid-mixing polymerization of m-aminophenol in the presence of a CNF mat for flexible solid-state supercapacitors. The surface compositions, morphology and pore structure of the hybrid mats were characterized by using various techniques, e.g., FTIR, Raman, XRD, FE-SEM, TEM, and N2 absorption. The results show that the PmAP nanoparticles were homogeneously deposited on CNF surfaces and formed a thin flexible hybrid mat, which were directly used to made electrodes for electrochemical analysis without using any binders or conductive additives. The electrochemical performances of the hybrid mats were easily tailored by varying the PmAP loading on a hybrid electrode. The PmAP/CNF-10 hybrid electrode with a relatively low PmAP loading (> 42 wt%) showed a high specific capacitance of 325.8 F g-1 and a volumetric capacitance of 273.6 F cm-3 at a current density of 0.5 A g-1, together with a specific capacitance retention of 196.2 F g-1 at 20 A g-1. The PmAP/CNF-10 hybrid electrode showed good cycling stability with 88.2% capacitance retention after 5000 cycles. A maximum energy density of 45.2 Wh kg-1 and power density of 20.4 kW kg-1 were achieved for the PmAP/CNF-10 hybrid electrode. This facile and cost-effective synthesis of a flexible binder-free PmAP/CNF hybrid mat with excellent capacitive performances encourages its possible commercial exploitation.
ACS Sustainable Chemistry & Engineering, 2017
Freestanding nitrogen-doped porous carbon nanofibres (NCNFs) mats were prepared by electrospinnin... more Freestanding nitrogen-doped porous carbon nanofibres (NCNFs) mats were prepared by electrospinning of polyacrylonitrile/poly(m-aminophenol) (PAN/PmAP) precursor blends with different polymeric compositions followed by thermal stabilization and carbonization. The morphology, pore structure and surface elemental compositions of as-prepared NCNFs were characterized by different techniques such as scanning electron microscopy, transmission electron microscopy, N 2 adsorption, Raman spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The charge-storage capability of the fabricated NCNFs was investigated in KOH electrolyte. The electrochemical performances of NCNFs were evaluated by varying the PmAP loading in the blend compositions. The highest specific capacitance of 347.5 F g-1 at 0.5 mA cm-2 together with a capacitance retention of 173.2 F g-1 at 20 mA cm-2 was achieved for the PAN:PmAP (85:15 w/w) NCNFs (NCNF 85:15). The volumetric capacitance of 200.8 F cm-3 at 0.5 mA cm-2 was recorded for the NCNF 85:15. The NCNF 85:15 showed the maximum energy density of 12.1 Wh kg-1 at 0.093 kW kg-1 and good cycling stability with 90.5% capacitance retention after 10000 cycles. The excellent capacitive performances of the NCNF 85:15 was attributed to high effective surface area, high content of mesoporosity, good conducvity and high fraction of hetero-atom doped carbon, which result in both electrochemical double layer and Faradaic capacitance contributions.
Journal of Power Sources, 2004
One of the key points to develop a cost-effective direct alcohol fuel cell (DAFC) is to investiga... more One of the key points to develop a cost-effective direct alcohol fuel cell (DAFC) is to investigate cheaper electrocatalysts for the oxidation of alcohol at the anode, allowing an increase in the current density and a decrease in the anodic overvoltage. In this respect, polycrystalline deposits of platinum and platinum-ruthenium on a CuNi (70:30) alloy support are investigated here. Electro-oxidation of ethanol in 0.5 M NaOH is studied over these electrodes. Cyclic voltammetry, steady state polarization and electrochemical impedance spectroscopy are used to investigate the kinetics and mechanism of ethanol electro-oxidation. Efforts are also made to correlate the catalytic activity of such electrodes with their surface morphology.
International Journal of Hydrogen Energy, 2011
Electrochimica Acta, 2010
Ethanol has been recognized as the ideal fuel for direct alcohol fuel cell (DAFC) systems due to ... more Ethanol has been recognized as the ideal fuel for direct alcohol fuel cell (DAFC) systems due to its high energy density, non-toxicity and its bio-generation. However the complete conversion of ethanol to CO 2 is still met with challenges, due to dearth of suitable catalysts for the electro-oxidation. In the present work the effect of temperature on the catalytic oxidation of ethanol in alkaline medium over electrodeposited Pt and Pt-Pd alloyed nano particles on carbon support and also on the product formation during the course of reaction have been studied within the temperature range of 20-80 • C. The information on surface morphology, structural characteristics and bulk composition of the catalyst was obtained using SEM, XRD and EDX. BET surface area and pore widths of the catalyst particles were calculated by applying the BET equation to the adsorption isotherms. The electrochemical techniques like cyclic voltammetry, chronoamperometry and impedance spectroscopy were employed to investigate the electrochemical parameters related to electro-oxidation of ethanol in alkaline pH on the catalyst surfaces under the influence of temperature. The results show that the oxidation kinetics of ethanol on the alloyed Pt-Pd/C catalysts is significantly improved compared to that on Pt alone. The observations were interpreted in terms of the synergistic effect of higher electrochemical surface area, preferred OH − adsorption on the surface and the ad-atom contribution of the alloyed matrix. A pronounced influence of temperature on the reaction kinetics was manifested in the diminution of charge transfer resistance and activation energy of the ethanol oxidation with Pd incorporation into the Pt matrix, ensuring greater tolerance of the alloyed catalyst towards ethanolic residues. The higher yield of the reaction products like acetate and CO 3 −2 on the alloyed catalyst compared to Pt alone in alkaline medium, as estimated by ion chromatography, further substantiates the catalytic superiority of the Pt-Pd/C catalyst over Pt/C.
International Journal of Hydrogen Energy, 2011
In the present investigation, Vulcan XC-72 supported Pt and Pt based binary and ternary catalysts... more In the present investigation, Vulcan XC-72 supported Pt and Pt based binary and ternary catalysts (Pt/C, PtPd/C, PtAu/C, PtPdAu/C) have been synthesized under borohydride reduction scheme and applied for the study of the electro-oxidation of ethanol in alkaline media at room temperature. The surface morphology of the catalysts was determined by XRD (X-ray diffraction) & TEM (transmission electron microscopy) analysis. XRD patterns reveal that all the catalysts have disordered face center cubic lattice structures. Low resolution TEM images reveal uniform dispersion of metal nano particles on carbon support having an average size of 3e4.5 nm. HRTEM is also carried out for the determination of the distance between the lattice planes. Different textural properties including external surface area, pore volume and widths of the catalyst matrix were calculated by applying the BET equation to the adsorption isotherms. During electrolysis substantial increase in anodic peak current was observed for ethanol oxidations when the second and third metal component was introduced into the Pt matrix as in case of PtPdAu/C catalysts. The charge transfer resistance (R ct) for ethanol oxidation was substantially reduced from 87.9 U on Pt/C to 7.74 U on PtPdAu/C demonstrating the superior electrode kinetics behavior of the latter over the other catalysts studied. Thus Au and Pd incorporation into the Pt matrix not only increases the catalytic efficiency of the alloyed catalyst but at the same time effectively reduces the Pt content in the ternary system.
Background: Chromophobe renal cell carcinoma (ChRCC) is the second common subtype of non-clear ce... more Background: Chromophobe renal cell carcinoma (ChRCC) is the second common subtype of non-clear cell renal cell carcinoma (nccRCC), which accounting for 4-5% of renal cell carcinoma (RCC). However, there is no effective biomarker to predict clinical outcomes of this malignant disease. Bioinformatic methods may provide a feasible potential to solve this problem. Methods: In this study, differentially expressed genes (DEGs) of ChRCC samples on The Cancer Genome Atlas database were filtered out to construct co-expression modules by weighted gene co-expression network analysis and the key module were identified by calculating module-trait correlations. Functional analysis was performed on the key module and candidate hub genes were screened out by co-expression and MCODE analysis. Afterwards, real hub genes were filter out in an independent dataset GSE15641 and validated by survival analysis. Results: Overall 2215 DEGs were screened out to construct eight co-expression modules. Brown module was identified as the key module for the highest correlations with pathologic stage, neoplasm status and survival status. 29 candidate hub genes were identified. GO and KEGG analysis demonstrated most candidate genes were enriched in mitotic cell cycle. Three real hub genes (SKA1, ERCC6L, GTSE-1) were selected out after mapping candidate genes to GSE15641 and two of them (SKA1, ERCC6L) were significantly related to overall survivals of ChRCC patients. Conclusions: In summary, our findings identified molecular markers correlated with progression and prognosis of ChRCC, which might provide new implications for improving risk evaluation, therapeutic intervention, and prognosis prediction in ChRCC patients.
Materials Characterization, 2009
Electropolymerization of aniline at the graphite electrodes was achieved by potentiodynamic metho... more Electropolymerization of aniline at the graphite electrodes was achieved by potentiodynamic method. Electrodeposition of Pd (C-PANI-Pd) and Ni (C-PANI-Ni) and codeposition of Pd-Ni (C-PANI-Pd-Ni) microparticles into the polyaniline (PANI) film coated graphite (C-PANI) were carried out under galvanostatic control. The morphology and composition of the composite electrodes were obtained using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) techniques. The electrochemical behavior and electrocatalytic activity of the electrode were characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometric (CA) methods in acidic medium. The C-PANI-Pd-Ni electrode showed an improved catalytic performance towards methanol oxidation in terms of lower onset potential, higher anodic oxidation current, greater stability, lower activation energy, and lower charge transfer resistance. The enhanced electrocatalytic activity might be due to the greater permeability of C-PANI films for methanol molecules, better dispersion of Pd-Ni microparticles into the polymer matrixes, and the synergistic effects between the dispersed metal particles and their matrixes.