Microporous Carbon and Carbon/Metal Composite Materials Derived from Bio-Benzoxazine-Linked Precursor for CO2 Capture and Energy Storage Applications

There is currently a pursuit of synthetic approaches for designing porous carbon materials with selective CO2 capture and/or excellent energy storage performance that significantly impacts the environment and the sustainable development of circular economy. In this study we prepared a new bio-based benzoxazine (AP-BZ) in high yield through Mannich condensation of apigenin, a naturally occurring phenol, with 4-bromoaniline and paraformaldehyde. We then prepared a PA-BZ porous organic polymer (POP) through Sonogashira coupling of AP-BZ with 1,3,6,8-tetraethynylpyrene (P-T) in the presence of Pd(PPh3)4. In situ Fourier transform infrared spectroscopy and differential scanning calorimetry revealed details of the thermal polymerization of the oxazine rings in the AP-BZ monomer and in the PA-BZ POP. Next, we prepared a microporous carbon/metal composite (PCMC) in three steps: Sonogashira coupling of AP-BZ with P-T in the presence of a zeolitic imidazolate framework (ZIF-67) as a directing hard template, affording a PA-BZ POP/ZIF-67 composite; etching in acetic acid; and pyrolysis of the resulting PA-BZ POP/metal composite at 500 °C. Powder X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller (BET) measurements revealed the properties of the as-prepared PCMC. The PCMC material exhibited outstanding thermal stability (Td10 = 660 °C and char yield = 75 wt%), a high BET surface area (1110 m2 g–1), high CO2 adsorption (5.40 mmol g–1 at 273 K), excellent capacitance (735 F g–1), and a capacitance retention of up to 95% after 2000 galvanostatic charge–discharge (GCD) cycles; these characteristics were excellent when compared with those of the corresponding microporous carbon (MPC) prepared through pyrolysis of the PA-BZ POP precursors with a ZIF-67 template at 500 °C.

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Process optimization of biodiesel production catalyzed by CaO nanocatalyst using response surface methodology

Journal of Nanostructure in Chemistry ◽

10.1007/s40097-019-00317-w ◽

2019 ◽

Vol 9 (4) ◽

pp. 269-280 ◽

Cited By ~ 4

Author(s):

Priyanka Bharti ◽

Bhaskar Singh ◽

R. K. Dey

Keyword(s):

Electron Microscopy ◽

Reaction Temperature ◽

Active Sites ◽

High Surface ◽

Raw Material ◽

Biodiesel Production ◽

Bet Surface Area ◽

Molar Ratio ◽

High Yield ◽

Catalyst Amount

Abstract Uses of nanocatalysts have become more useful in optimizing catalytic reactions. They are known to enhance the rate of reaction by offering a greater number of active sites by possessing a high surface-to-volume ratio. In the present work, calcium oxide nanocatalysts were synthesized through the sol–gel method. The particle size of the nanocatalyst prepared ranged up to 8 nm. Soybean oil was used as the raw material for the synthesis of biodiesel. The synthesized nano-CaO was characterized through scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and BET (Brunauer–Emmett–Teller). Average BET surface area analysis of the nanocatalyst was calculated to be 67.781 m2/g and pore diameter was 3.302 nm. Nano-CaO catalyst was used to synthesize biodiesel and optimize the reaction variables through optimization processes to achieve a high yield of biodiesel. The reaction variables that were optimized were catalyst amount, oil to methanol molar ratio and reaction temperature. Upon optimization, the conversion of biodiesel was found to be 97.61%. The optimized value of the reaction variables was: catalyst amount of 3.675 wt% with respect to oil, molar ratio (alcohol to oil) of 11:1, and reaction temperature of 60 °C for 2 h. Graphic abstract

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Quality films from carbon fiber evaporation for thorough coverage of TEM grids

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104157 ◽

1988 ◽

Vol 46 ◽

pp. 418-419

Author(s):

N. Tempel ◽

M. C. Ledbetter

Keyword(s):

Electron Microscopy ◽

High Resolution Electron Microscopy ◽

Carbon Films ◽

Low Noise ◽

Vacuum Evaporation ◽

High Yield ◽

Good Adhesion ◽

Noise Structure ◽

Resolution Electron ◽

Carbon Foils

Carbon films have been a support of choice for high resolution electron microscopy since the introduction of vacuum evaporation of carbon. The desirable qualities of carbon films and methods of producing them has been extensively reviewed. It is difficult to get a high yield of grids by many of these methods, especially if virtually all of the windows must be covered with a tightly bonded, quality film of predictable thickness. We report here a method for producing carbon foils designed to maximize these attributes: 1) coverage of virtually all grid windows, 2) freedom from holes, wrinkles or folds, 3) good adhesion between film and grid, 4) uniformity of film and low noise structure, 5) predictability of film thickness, and 6) reproducibility.Our method utilizes vacuum evaporation of carbon from a fiber onto celloidin film and grid bars, adhesion of the film complex to the grid by carbon-carbon contact, and removal of the celloidin by acetone dissolution. Materials must be of high purity, and cleanliness must be rigorously maintained.

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Synthesis and Electrochemical Properties of NiFe-Se/rGO Nanocomposites

Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) ◽

10.2174/2405520413999200702160750 ◽

2020 ◽

Vol 13 ◽

Author(s):

Rouwei Yan ◽

Biao Xu ◽

K. P. Annamalai ◽

Tianlu Chen ◽

Zhiming Nie ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Energy Storage ◽

Synergistic Effects ◽

Nitrogen Adsorption ◽

Storage Device ◽

Energy Storage And Conversion ◽

Step Method ◽

Practical Applications ◽

Device Applications

Background : Renewable energies are in great demand because of the shortage of traditional fossil energy and the associated environmental problems. Ni and Se-based materials are recently studied for energy storage and conversion owing to their reasonable conductivities and enriched redox activities as well as abundance. However, their electrochemical performance is still unsatisfactory for practical applications. Objective: To enhance the capacitance storage of Ni-Se materials via modification of their physiochemical properties with Fe. Methods: A two-step method was carried out to prepare FeNi-Se loaded reduced graphene oxide (FeNi-Se/rGO). In the first step, metal salts and graphene oxide (GO) were mixed under basic condition and autoclaved to obtain hydroxide intermediates. As a second step, selenization process was carried out to acquire FeNi-Se/rGO composites. Results: X-ray diffraction measurements (XRD), nitrogen adsorption at 77K, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were carried out to study the structures, porosities and the morphologies of the composites. Electrochemical measurements revealed that FeNi-Se/rGO notably enhanced capacitance than the NiSe/G composite. This enhanced performance was mainly attributed to the positive synergistic effects of Fe and Ni in the composites, which not only had influence on the conductivity of the composite but also enhanced redox reactions at different current densities. Conclusion: NiFe-Se/rGO nanocomposites were synthesized in a facile way. The samples were characterized physicochemically and electrochemically. NiFeSe/rGO giving much higher capacitance storage than the NiSe/rGO explained that the nanocomposites could be an electrode material for energy storage device applications.

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Identification of Tomato Infecting Viruses That Co-Isolate with Nanovesicles Using a Combined Proteomics and Electron-Microscopic Approach

Nanomaterials ◽

10.3390/nano11081922 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1922

Author(s):

Ramila Mammadova ◽

Immacolata Fiume ◽

Ramesh Bokka ◽

Veronika Kralj-Iglič ◽

Darja Božič ◽

...

Keyword(s):

Electron Microscopy ◽

Mosaic Virus ◽

Protein Identification ◽

Plant Viruses ◽

Size Exclusion ◽

Tomato Mosaic Virus ◽

High Yield ◽

Plant Resources ◽

Electron Microscopic ◽

Viral Particles

Plant-derived nanovesicles (NVs) have attracted interest due to their anti-inflammatory, anticancer and antioxidative properties and their efficient uptake by human intestinal epithelial cells. Previously we showed that tomato (Solanum lycopersicum L.) fruit is one of the interesting plant resources from which NVs can be obtained at a high yield. In the course of the isolation of NVs from different batches of tomatoes, using the established differential ultracentrifugation or size-exclusion chromatography methods, we occasionally observed the co-isolation of viral particles. Density gradient ultracentrifugation (gUC), using sucrose or iodixanol gradient materials, turned out to be efficient in the separation of NVs from the viral particles. We applied cryogenic transmission electron microscopy (cryo-TEM), scanning electron microscopy (SEM) for the morphological assessment and LC–MS/MS-based proteomics for the protein identification of the gradient fractions. Cryo-TEM showed that a low-density gUC fraction was enriched in membrane-enclosed NVs, while the high-density fractions were rich in rod-shaped objects. Mass spectrometry–based proteomic analysis identified capsid proteins of tomato brown rugose fruit virus, tomato mosaic virus and tomato mottle mosaic virus. In another batch of tomatoes, we isolated tomato spotted wilt virus, potato virus Y and southern tomato virus in the vesicle sample. Our results show the frequent co-isolation of plant viruses with NVs and the utility of the combination of cryo-TEM, SEM and proteomics in the detection of possible viral contamination.

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Continuous Synthesis of Nanodroplet-Templated, N-Doped Microporous Carbon Spheres in Microfluidic System for CO2 Capture

ACS Applied Materials & Interfaces ◽

10.1021/acsami.0c14044 ◽

2020 ◽

Vol 12 (47) ◽

pp. 52571-52580

Author(s):

Ziheng Jin ◽

Xia Jiang ◽

Zhongde Dai ◽

Lingling Xie ◽

Wei Wang ◽

...

Keyword(s):

Co2 Capture ◽

Microfluidic System ◽

Microporous Carbon ◽

Carbon Spheres ◽

Continuous Synthesis

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Coupling anodic/cathodic energy storage through in-situ heterostructure regulation of ordered microporous carbon for sodium-ion hybrid capacitors

Journal of Materials Chemistry A ◽

10.1039/d0ta11093k ◽

2021 ◽

Author(s):

Juan Li ◽

Bo Wang ◽

Tianzhao Hu ◽

Yuzuo Wang ◽

Zhenhua Sun ◽

...

Keyword(s):

Energy Storage ◽

Power Output ◽

Microporous Carbon ◽

Sodium Ion ◽

Faradaic Reaction ◽

Hybrid Capacitors

Sodium-ion hybrid capacitors are emerging as the promising energy storage and power output devices. However, they suffer from sluggish faradaic reaction of anode and low capacity of cathode. Zeolite-templated carbons...

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Synthesis of high surface area and functionalized nanoporous biocarbons and their efficiency for CO2 capture and supercapacitors

Green Chemistry ◽

10.1039/d1gc01376a ◽

2021 ◽

Author(s):

Gurwinder Singh ◽

Rohan Bahadur ◽

Ajanya Maria Ruban ◽

Jefrin Marykala Davidraj ◽

Dawei Su ◽

...

Keyword(s):

Energy Storage ◽

Surface Area ◽

Co2 Capture ◽

Water Purification ◽

High Surface ◽

High Surface Area ◽

Energy Storage And Conversion ◽

Waste Biomass ◽

Fabrication Technology ◽

Significant Attention

Nanoporous biocarbons derived from waste biomass have created significant attention owing to their great potential for energy storage and conversion and water purification. However, the fabrication technology for these materials...

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Solid-State Ball-Milling of Co3O4 Nano/Microspheres and Carbon Black Endorsed LaMnO3 Perovskite Catalyst for Bifunctional Oxygen Electrocatalysis

Catalysts ◽

10.3390/catal11010076 ◽

2021 ◽

Vol 11 (1) ◽

pp. 76

Author(s):

Chelladurai Karuppiah ◽

Balamurugan Thirumalraj ◽

Srinivasan Alagar ◽

Shakkthivel Piraman ◽

Ying-Jeng Jame Li ◽

...

Keyword(s):

Electron Microscopy ◽

Energy Storage ◽

Fuel Cell ◽

Solid State ◽

Carbon Black ◽

Ball Milling ◽

Potential Candidate ◽

X Ray ◽

Bifunctional Electrocatalyst ◽

Bet Analysis

Developing a highly stable and non-precious, low-cost, bifunctional electrocatalyst is essential for energy storage and energy conversion devices due to the increasing demand from the consumers. Therefore, the fabrication of a bifunctional electrocatalyst is an emerging focus for the promotion and dissemination of energy storage/conversion devices. Spinel and perovskite transition metal oxides have been widely explored as efficient bifunctional electrocatalysts to replace the noble metals in fuel cell and metal-air batteries. In this work, we developed a bifunctional catalyst for oxygen reduction and oxygen evolution reaction (ORR/OER) study using the mechanochemical route coupling of cobalt oxide nano/microspheres and carbon black particles incorporated lanthanum manganite perovskite (LaMnO3@C-Co3O4) composite. It was synthesized through a simple and less-time consuming solid-state ball-milling method. The synthesized LaMnO3@C-Co3O4 composite was characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, Brunauer-Emmett-Teller (BET) analysis, X-ray diffraction spectroscopy, and micro-Raman spectroscopy techniques. The electrocatalysis results showed excellent electrochemical activity towards ORR/OER kinetics using LaMnO3@C-Co3O4 catalyst, as compared with Pt/C, bare LaMnO3@C, and LaMnO3@C-RuO2 catalysts. The observed results suggested that the newly developed LaMnO3@C-Co3O4 electrocatalyst can be used as a potential candidate for air-cathodes in fuel cell and metal-air batteries.

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