CoFe2O4- mesoporous carbons derived from Eucommia ulmoides wood for supercapacitors: Comparison of two activation method and composite carbons material synthesis method

2021 ◽  
Vol 171 ◽  
pp. 113861
Author(s):  
Zhou Liao ◽  
Hong-Yu Su ◽  
Jie Cheng ◽  
Guo-Tao Sun ◽  
Lin Zhu ◽  
...  
2020 ◽  
Vol 73 (7) ◽  
pp. 587
Author(s):  
Sitong Guo ◽  
Wen Tan ◽  
Jiyicheng Qiu ◽  
Jinlong Du ◽  
Zhanxu Yang ◽  
...  

As a popular material synthesis method, spatially confined reactions have been gradually recognised for their excellent performance in the field of current materials synthesis. In recent years, molybdenum-based catalysts have gradually gained recognition due to high natural reserves of Mo, its low cost, and many other advantages, and they have wide applications in the area of functional materials, especially in topical areas such as batteries and electrocatalysts. In this context, spatially confined reactions have become widely to obtain various types of molybdenum-based electrode materials and electrocatalysts which result in an excellent morphology, structure, and performance. In this review, the concept of a spatially confined reaction system and the electrochemical application (electrode materials and electrocatalyst) of molybdenum-based materials synthesised in this way are comprehensively discussed. The current problems and future development and application of molybdenum-based materials are also discussed in this review.


2018 ◽  
Vol 24 (8) ◽  
pp. 5532-5536
Author(s):  
M. A Mary Thangam ◽  
Chellapandian Kannan

The mesoporous materials have variety of applications in several field particularly it has a main role in Catalysis, Petrochemical industries and Adsorption. Normally the porous material has well ordered 3Dimensional structure, huge surface area, high thermal stability and active acid sites. The properties of these materials can be varied because it is mostly depends on its template, synthesis method and isomorphous substitution of metal ions. There are two major mesoporous materials which are aluminosilicate and aluminophosphate. In this present investigation AlCl3 and FeCl3 are used in equal amount for the synthesis of mesoporous material. The synthesized material is characterized by FT-IR, XRD, TGA, BET, EDAX and TPD. Morphological images were studied by SEM. These characterization techniques confirm the formation of mesoporous molecular sieves.


2021 ◽  
Vol 6 (2) ◽  
pp. 39-52
Author(s):  
Jaya Edianta ◽  
Nanang Fauzi ◽  
Marzuki Naibaho ◽  
Fitri Suryani Arsyad ◽  
Idha Royani

Betel leaf is a typical Indonesian herbal plant that propagates on other tree trunks. So far, betel leaf has only been used in biomedicine and traditional medicine, whereas the chemical compounds of betel leaf can be used to absorb electromagnetic waves. In this mini-review, we review several research results to discuss the potential effectiveness of betel leaf in barium hexaferrite as an absorber of electromagnetic radiation. We compiled this mini-review based on the literature review method that is discussed extensively and in-depth regarding the chemical composition of betel leaf, modification of the development of barium hexaferrite material with betel leaf media extract, characteristics of BaFe12O19 as absorption of electromagnetic waves, and the effectiveness of media extracts in BaFe12O19 as absorption of electromagnetic waves. Based on the results of the literature review, the modification of BaFe12O19 material synthesis can include microemulsion, solid-state, coprecipitation, sol-gel, and hydrothermal synthesis. So far, hydrothermal synthesis is a synthesis method of mixing betel leaf extract media and ferrite-based magnets that have been studied before. Betel leaf in ferrite-based magnetic materials has been studied not to damage the surface morphology and characteristics of the magnetic material. The results of the assessment also show the effectiveness of adding other elements or compounds such as Ni, Al2O3, and composites in ferrite-based magnetic materials that can absorb more than 90% of electromagnetic waves in the frequency range 2-18 GHz.


Author(s):  
Norbert Német ◽  
Ylenia Miele ◽  
Gábor Shuszter ◽  
Eszter L. Tóth ◽  
János Endre Maróti ◽  
...  

AbstractIn the past decade, much effort has been devoted to using chemical clock-type reactions in material design and driving the self-assembly of various building blocks. Urea-urease enzymatic reaction has chemical pH clock behavior in an unbuffered medium, in which the induction time and the final pH can be programmed by the concentrations of the reagents. The urea-urease reaction can offer a new alternative in material synthesis, where the pH and its course in time are crucial factors in the synthesis. However, before using it in any synthesis method, it is important to investigate the possible effects of the reagents on the enzymatic reaction. Here we investigate the effect of the reagents of the zeolite imidazole framework-8 (zinc ions and 2-methylimidazole) on the urea-urease reaction. We have chosen the zeolite imidazole framework-8 because its formation serves as a model reaction for the formation of other metal–organic frameworks. We found that, besides the inhibition effect of the zinc ions which is well-known in the literature, 2-methylimidazole inhibits the enzymatic reaction as well. In addition to the observed inhibition effect, we report the formation of a hybrid urease-zinc-2-methylimidazole hybrid material. To support the inhibition effect, we developed a kinetic model which reproduced qualitatively the experimentally observed kinetic curves.


2013 ◽  
Vol 757 ◽  
pp. 197-216 ◽  
Author(s):  
Arvind Kumar ◽  
Jaspreet Kaur Rajput

Polymer nanocomposites are now a days an area of increasing scientific as well as technical interest. The addition of variable percents of nano sized materials creates change in their property (ies). Polymer nanocomposites exhibit superior properties as compared to micro- or macrocomposites. The improved combinations of electrical, mechanical and thermal properties of nanocomposites have resulted in major interest in various electronic applications. Polymer nanocomposites can be synthesized for various applications by proper selection of matrix, nano reinforcement material, synthesis method and surface modification of either the reinforcement or polymer (if required). Many polymer nanocomposites based products have been commercialized. This chapter has tried to highlight various types of polymer nanocomposites, their unique properties, various electronic applications for sensors with some specific examples. Though it is not a comprehensive one, this chapter could give a basic idea about polymer nanocomposites for sensor technology to a beginner.


2018 ◽  
Vol 1087-1088 ◽  
pp. 6-13 ◽  
Author(s):  
Guotong Qin ◽  
Jing Ma ◽  
Wei Wei ◽  
Jaja Li ◽  
Fangqing Yue

2021 ◽  
Vol 17 (1) ◽  
pp. 1-17
Author(s):  
Jacson Victor Morin ◽  
Darma Santi

Research has been carried out on the H2S gas sensor made of TiO2-Ni/Al2O3 which is connected to an automatic vacuum. The results showed that the optimum conditions for the variation of Ni doping metal levels were 20 mg / gram TiO2. The semiconductor material synthesis method used the sol gel method with TTiP precursor which was made at pH 7. Coating of the sol gel solution on the Al2O3 substrate used a dip coater with a decrease speed of 1 cm / minute and was carried out 7 times of immersion. The characterization of synthetic results used UVVis, XRD, FTIR and SEM-EDX. The band gap value resulting from Ni doping is 2.75 eV from 3.2 eV, XRD identification shows that TiO2 is anataseic and detected at 2θ. FTIR data also supports XRD results with detection of TiO2, Ni-O, NiTiO3, Ti-O-Ni, and Ti-O-Ti groups. TiO2-Ni / Al2O3 sensor test results are very sensitive and selective to H2S gas. Arduino Uno sensor and microcontroller connectivity can change the unit of resistance into a unit of ppm concentration and can drive the exhaust (vacuum) automatically in the laboratory room or chemical storage space when there is H2S.


1989 ◽  
Vol 44 (11) ◽  
pp. 1421-1422 ◽  
Author(s):  
Michael D. Figueroa
Keyword(s):  

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