scholarly journals The Utilization of Carbon Dioxide to Prepare TiCxOy Films with Low Friction and High Anti-Corrosion Properties

Coatings ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 533
Author(s):  
Kaixiong Gao ◽  
Zhaolong Wang ◽  
Qian Jia ◽  
Bin Zhang ◽  
Zhixing Mou ◽  
...  

Recycling carbon dioxide (CO2) for weakening the greenhouse effect is still an outstanding question. Although many chemical methods have been designed for CO2 conversion, they is still a need to develop new ways for CO2 recycling. Plasma methods were employed to convert CO2 into energy molecules, with the addition of H2, H2O and so on. Non heavy elements, like Ti, Cr, Si and Mo and so forth, were employed to take part in a reactive process, which might be very interesting for special scientific interest. In this work, magnetron sputtering method was used not only for igniting the plasma but also for providing Ti elements involved in reactions, via the selected Ti target. One can confirm that the TiCxOy films were successfully grew via sputtering a Ti target in CO2 atmosphere with Ar as dilute gas, which proved that CO2 is a key player in the matter of the involvement of excited CO2+, CO+, CO3− and so on, in the growth process reacting with Ti ions. The TiCxOy films exhibit the highest hardness (20.3 GPa), lowest friction coefficient (0.065) and the best corrosion resistance. The growth of the TiCxOy films are not only a new strategy for consuming CO2 but also a good way for reusing it for preparing TiCxOy films with high hardness for anti-corrosion and reducing friction. Moreover, reducing CO2 emissions via energy saving (through reducing friction and corrosion resistance) and recycling existing CO2 are both important for mitigating the greenhouse effect.

Author(s):  
L. Rama Krishna ◽  
G. Sundararajan

This article presents the brief overview of fairly recent and eco-friendly micro arc oxidation (MAO) coating technology. The weight-cost-performance benefits in general raised the interest to utilize lightweight materials, especially the aluminum and its alloys. Despite numerous engineering advantages, the aluminum alloys themselves do not possess suitable tribology and corrosion resistance. Therefore, improvements in surface properties are essential to enable developing potential industrial applications. For improving wear and corrosion resistance of Al alloys, the most demanding surface properties are high hardness and chemical inertness. The technical and technological limitations associated with traditional anodizing and hard anodizing processes have been the strongest driving force behind the development of new MAO technology. While presenting the key technological elements associated with the MAO process, the basic mechanism of coating formation and its phase gradient nature is presented. Influence of various process parameters including the electrolyte composition has been discussed. The typical microstructural features and distribution of α- and γ-Al2O3 phases across the coating thickness as a key strategy to form dense coatings with required mechanical, tribological, and corrosion properties which are vital to meet potential application demands are briefly illustrated.


Coatings ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 767
Author(s):  
Ning Li ◽  
Hong Xu ◽  
Xinhui Li ◽  
Weizeng Chen ◽  
Lijuan Zheng ◽  
...  

Ni-Mo-ZrO2 composite coatings were produced by pulse electrodeposition technique from alkaline electrolytes containing dispersed ZrO2 nanopowder. The structure, microhardness, corrosion properties and tribological properties of Ni-Mo-ZrO2 composites with different content of molybdenum and ZrO2 have also been examined. Structural characterization was performed using X-ray diffraction (XRD) and a scanning electron microscope (SEM). It was found that an increase in molybdate concentration in the electrolyte affects the microstructure, microhardness, corrosion properties and tribological properties of the amount of co-deposited ZrO2 nanoparticles. The incorporation of ZrO2 nanoparticles into the Ni-Mo alloy matrix positively affects the microhardness and also slightly improves the corrosion properties of Ni-Mo alloy coatings. In addition, both the coefficient of friction and the salt-water lubrication sliding wear rate of Ni-Mo-ZrO2 coatings decreased with increasing the ZrO2 content. Wear test and corrosion resistance test results indicated that the intermetallic composite had an excellent wear-resistance and corrosion resistance at room-temperature, which is attributed to the high hardness and strong atomic bonding of constituent phases Ni-Mo and polarization effect of ZrO2 nanoparticles.


2021 ◽  
Author(s):  
Qi-Su Huang ◽  
Wei Wei ◽  
Bing-Jie Ni

Photocatalytic carbon dioxide (CO2) conversion is a promising technology to address the greenhouse effect and energy shortage problems by utilizing the inexhausted solar energy. However, the over-reliance of the metal-based...


2021 ◽  
Vol 5 (1) ◽  
pp. 11-16
Author(s):  
Noer Sarifah Ainy ◽  
Nestiyanto Hadi

The earth is experiencing global warming due to an increase in air temperature (greenhouse effect). This is due to the large number of greenhouse gases produced by human activities. In addition, it is also due to the reduced number of plants that absorb greenhouse gases, especially carbon dioxide. This condition causes the study of the greenhouse effect to become an object studied by students at school. Understanding the greenhouse effect is somewhat difficult if only understood in theory. Increasing understanding can be done by making practicum learning media. This study aims to create learning media for the Greenbox Effect Simulator to help understand the concept of the greenhouse effect. The research was conducted using control variables and independent variables (use of plants and without plants). The plants used are Caisim, Sri Gading and Anggrek. The presence of carbon dioxide (CO2) greenhouse gases can be detected by three things, namely changes in the color of the CO2 indicator, changes in temperature, and visibility of the box. The color of the CO2 indicator shows green and green yellow for Box B (with plants) which means the concentration of CO2 in normal conditions. Whereas Box C (without plants) gives a yellow color, which means that the concentration of CO2 is at high conditions. The presence of carbon dioxide gas from combustion will increase the temperature by 1.4 - 1.9 oC in Box C (without plants) and 0.7 - 1.5 oC in Box B (use of plants). The visibility of Box B shows a higher brightness level than Box C. The best plants that can absorb CO2 concentrations are orchids. The ability of orchids to absorb CO2 is assisted by their roots which also function to carry out photosynthesis. The existence of plants functions to absorb CO2 quite well when viewed from changes in temperature, color indicators and visibility.


Author(s):  
Paulo Renda Anderson ◽  
Carlos Mergulhão Júnior ◽  
Moacy José Stoffes Junior ◽  
Cléver Reis Stein

This article describes the construction of a complete experimental apparatus to simulate the greenhouse and global warming for educatioal use. These demonstrations are fundamental for people understand the importance of greenhouse effect to keep that life continues on earth and, know about climate change and the causes of global warming. For development of this devise we used an Arduino UNO, temperature and pressure sensors, and low cost products. The experimental results showed that the average atmosphere temperature increases with the increasing concentration of carbon dioxide (CO2). Moreover, this apparatus can be used in classroom to demonstration these important global phenomena.


2018 ◽  
Author(s):  
Mohit Kapoor ◽  
Pratibha Chand-Thakuri ◽  
Michael Young

Carbon-carbon bond formation by transition metal-catalyzed C–H activation has become an important strategy to fabricate new bonds in a rapid fashion. Despite the pharmacological importance of <i>ortho</i>-arylbenzylamines, however, effective <i>ortho</i>-C–C bond formation from C–H bond activation of free primary and secondary benzylamines using Pd<sup>II</sup> remains an outstanding challenge. Presented herein is a new strategy for constructing <i>ortho</i>-arylated primary and secondary benzylamines mediated by carbon dioxide (CO<sub>2</sub>). The use of CO<sub>2</sub> is critical to allowing this transformation to proceed under milder conditions than previously reported, and that are necessary to furnish free amine products that can be directly used or elaborated without the need for deprotection. In cases where diarylation is possible, a chelate effect is demonstrated to facilitate selective monoarylation.


Alloy Digest ◽  
1971 ◽  
Vol 20 (8) ◽  

Abstract REYNOLDS 390 and A390 are hypereutectic aluminum-silicon alloys having excellent wear resistance coupled with good mechanical properties, high hardness, and low coefficients of expansion. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fatigue. It also includes information on high temperature performance and corrosion resistance as well as casting, heat treating, and machining. Filing Code: Al-203. Producer or source: Reynolds Metals Company.


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