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Paul J Chen - One of the best experts on this subject based on the ideXlab platform.
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introduction of an yttrium manganese Binary Composite that has extremely high adsorption capacity for arsenate uptake in different water conditions
Industrial & Engineering Chemistry Research, 2015Co-Authors: Paul J ChenAbstract:Arsenic contamination in natural water has become a global issue because of arsenic’s high toxicity, accumulation in the human body, and carcinogenicity. In this study, a new yttrium–manganese Binary Composite was developed by a one-step coprecipitation method. The mean diameter of the adsorbent was 6.3 μm, and the point of zero charge was 7.1. The adsorbent had a chemical formula of Y5Mn6O6(OH)12(CO3)5·5H2O according to the results obtained from the analysis of the element and functional group from X-ray photoelectron spectroscopy (XPS) study. The field emission scanning electron microscopy study showed that the adsorbent had a loose structure and was composed of nanosized flakes. The adsorption process was pH-dependent. The removal efficiency of arsenate by the adsorbent was much higher than that of arsenite. The optimal adsorption efficiency of arsenate was obtained at pH 6.0. The kinetics study showed that adsorption equilibrium of arsenate was reached within 25 h. The fit of the experimental data of ...
S Ramesh - One of the best experts on this subject based on the ideXlab platform.
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an enhanced performance of hybrid supercapacitor based on polyaniline manganese phosphate Binary Composite
Journal of Solid State Electrochemistry, 2017Co-Authors: Chee Ching Lee, Fatin Saiha Omar, Arshid Numan, Navaneethan Duraisamy, K Ramesh, S RameshAbstract:Manganese phosphate (Mn3(PO4)2) particles decorated polyaniline (PANI) have been proposed as a promising electrode material for supercapacitors. Mn3(PO4)2 particles were synthesized via the sonochemical method followed by calcination. The size of the particles was optimized by varying the sonication times: 30, 60, and 90 min which were labeled as M30, M60, and M90. The optimized Mn3(PO4)2 (M90) was blended with presynthesized PANI to form PANI-Mn3(PO4)2 Composite (PANI-M90). The phase structure and purity of the synthesized materials were authenticated via X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The morphological studies through field emission scanning electron microscopy (FESEM) showed that M90 particles are firmly anchored on branched-structured PANI which is beneficial for the quick transfer of charges. The electrochemical performance of M30, M60, M90, and PANI-M90 was investigated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) in 1 M KOH electrolyte. PANI-M90 exhibited significantly improved specific capacity (347 C/g) than M90 (88 C/g) at 1 A/g due to the augmentation of redox active sites and the synergistic effect between the conductive PANI and Mn3(PO4)2. Furthermore, the hybrid supercapacitor (activated carbon//PANI-M90) achieved a maximum energy density of 14.7 Wh/kg and a power density of 378 W/kg with 80% of capacity retention after 3000 charge-discharge cycles.
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Binary Composite of polyaniline copper cobaltite for high performance asymmetric supercapacitor application
Electrochimica Acta, 2017Co-Authors: Fatin Saiha Omar, Arshid Numan, Navaneethan Duraisamy, Mohammad Mukhlis Ramly, K Ramesh, S RameshAbstract:Abstract This article presents the effect of polyaniline (PANI) embedded copper cobaltite (CuCo 2 O 4 ) as an electrode material for high performance supercapacitor application. The Composite of PANI-CuCo 2 O 4 was prepared via blending process. The formation of PANI-CuCo 2 O 4 Composite was confirmed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analysis. The surface morphologies showed that the spinel structure of CuCo 2 O 4 (average particle size of 30 nm) was well distributed on PANI matrix, suggest the effective intercalation of CuCo 2 O 4 with PANI matrix. The electrochemical properties of CuCo 2 O 4 , PANI and PANI-CuCo 2 O 4 Composite were investigated using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) in 1 M of KOH as an aqueous electrolyte. The PANI-CuCo 2 O 4 Composite showed the improved specific capacitance of 403C/g than that of pure CuCo 2 O 4 and PANI.The enhanced electrochemical performance was obtained due to the augmentation of redox active sites and synergetic effect between PANI and CuCo 2 O 4 nanoparticles. Additionally, the fabricated (activated carbon (AC)/PANI-CuCo 2 O 4 ) asymmetric supercapacitor device can be cycled reversibly at a cell voltage of 1.5 V, which exhibited excellent electrochemical performances with an energy density of 76 Wh/kg and a power density of 599 W/kg. It also presented a superior life cycle with 94% capacitance retention after 3000 cycles.
Ferruccio Doghieri - One of the best experts on this subject based on the ideXlab platform.
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A fundamental study of the extent of meaningful application of Maxwell’s and Wiener’s equations to the permeability of Binary Composite materials. Part III: Extension of the Binary cubes model to 3-phase media
Chemical Engineering Science, 2015Co-Authors: John H Petropoulos, Kyriaki G Papadokostaki, Ferruccio Doghieri, Matteo MinelliAbstract:Abstract The simple cubic lattice model of cubic particles A dispersed in a continuous (polymeric) matrix B (and occupying a volume fraction 0≤ v A ≤1 therein), introduced in Parts I and II to establish the meaningful applicability of the Maxwell and Wiener equations to Binary Composite-medium permeability properties up to v A →1, is here applied to modeling the practically important case of a three-phase Composite medium, where the third phase is considered to take the (idealized) form of zones surrounding particles A which exhibit permeability properties differing substantially from those of the bulk matrix. It is shown, both theoretically and by application to various existing experimental data, that replacing the spherical particles, commonly assumed in such modeling, with cubic ones, leads to remarkable gains in model simplicity and internal consistency, in practical applicability, and ultimately in physical understanding of the observed variety of 3-phase Composite-medium permeability behavior.
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on the role of diffusivity ratio and partition coefficient in diffusional molecular transport in Binary Composite materials with special reference to the maxwell equation
Journal of Membrane Science, 2014Co-Authors: John H Petropoulos, Kyriaki G Papadokostaki, Matteo Minelli, Ferruccio DoghieriAbstract:Abstract A criticism is offered in this paper of conclusions stated in two recent works [Marand and Surapathi, J. Membr. Sci. 415 (2012) 871; Singh et al., J. Membr. Sci. 448 (2013) 160] with reference to properties of Composite materials which are relevant to the determination of steady state permeance of solute species. The discussion aims at clarifying conditions for the validity of “permeability models”, which claim for the role of the permeability ratio PA/PB in a Binary Composite of phases A and B, as the only parameter needed to estimate the overall relative effective permeability PM/PB, when size/shape distribution and arrangement of domains of the two phases are assigned. In this note, the thesis is rejected of a separate role for the solubility or partition coefficient in the performance of mixed matrix membranes and attention is driven to published numerical results which deserve to be revised.
J. Paul Chen - One of the best experts on this subject based on the ideXlab platform.
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Development and characterization of yttrium-ferric Binary Composite for treatment of highly concentrated arsenate wastewater.
Journal of Hazardous Materials, 2019Co-Authors: J. Paul ChenAbstract:Highly concentrated arsenic generated from industrial operation processes has posted a great thrust to humans. In this study, yttrium-ferric Binary Composite prepared through a simple co-precipitation method and applied for removing highly concentrated arsenic from the simulated arsenic-containing water. An optimal molar ratio of Y/Fe was determined as 8:1, which had a point of zero charge of around 7.0. The yttrium-ferric Binary Composite was aggregated by the nano-sized particles. The chemical state of yttrium and iron in the adsorbent was + III. The maximum adsorption capacities of the adsorbent towards arsenate (As(V)) were 401.8 mg-As/g at pH 4 and 288.7 mg-As/g at pH 7, respectively. A contact time of 8 h was sufficient to achieve 80% of the ultimate removal, faster than many reported/commercial water treatment materials. The existence of fluoride and phosphate ions significantly retarded the uptake of arsenic, indicating that likely the adsorbent was capable of adsorbing both contaminants. The mechanism study with several tools such as X-ray photoelectron spectroscopy (XPS) indicated that such functional groups as hydroxyl and carbonate groups participated in the As(V) adsorption process via ligand exchange followed by the inner-sphere complexation.
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Introduction of an Yttrium–Manganese Binary Composite That Has Extremely High Adsorption Capacity for Arsenate Uptake in Different Water Conditions
Industrial & Engineering Chemistry Research, 2015Co-Authors: J. Paul ChenAbstract:Arsenic contamination in natural water has become a global issue because of arsenic’s high toxicity, accumulation in the human body, and carcinogenicity. In this study, a new yttrium–manganese Binary Composite was developed by a one-step coprecipitation method. The mean diameter of the adsorbent was 6.3 μm, and the point of zero charge was 7.1. The adsorbent had a chemical formula of Y5Mn6O6(OH)12(CO3)5·5H2O according to the results obtained from the analysis of the element and functional group from X-ray photoelectron spectroscopy (XPS) study. The field emission scanning electron microscopy study showed that the adsorbent had a loose structure and was composed of nanosized flakes. The adsorption process was pH-dependent. The removal efficiency of arsenate by the adsorbent was much higher than that of arsenite. The optimal adsorption efficiency of arsenate was obtained at pH 6.0. The kinetics study showed that adsorption equilibrium of arsenate was reached within 25 h. The fit of the experimental data of ...
M. Sivakumar - One of the best experts on this subject based on the ideXlab platform.
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N-Doped Graphene Sheet Encapsulated Sulfur Binary Composite as Cathode for Lithium-Sulfur Battery Applications
Journal of Materials Engineering and Performance, 2020Co-Authors: P. Rajkumar, K. Diwakar, K. Krishnaveni, G. Radhika, R. Subadevi, R. M. Gnanamuthu, Fu-ming Wang, M. SivakumarAbstract:Herein, sulfur-/nitrogen-doped graphene (SNG) Binary Composite has been prepared by melt diffusion method and employed as cathode material for lithium-sulfur (Li-S) battery. The physical and electrochemical performances of prepared SNG Binary Composite were characterized using x-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscope, cyclic voltammetry and galvanostatic charge–discharge test. The SNG cathode delivers a high initial discharge capacity of 1135 mAh g^−1, and it sustains the capacity of 687 mAh g^−1 over the 50th cycle at 0.1C rate. The good electrochemical performance of SNG cathode is accredited to N-doping in graphene, which provides faster charge transfer pathway and suppresses the shuttle effect of polysulfides. The present study determines that the prepared SNG Composite is a suitable material for cathode in Li-S battery application.