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GeN-NxT Materials for Tire
Published in Anandhan Srinivasan, Selvakumar Murugesan, Arunjunai Raj Mahendran, Progress in Polymer Research for Biomedical, Energy and Specialty Applications, 2023
Partheban Manoharan, C. Harimohan
Cobalt can maintain different oxidation states and the ease by which electrons are transferred between these states may influence the migration of ions through the oxide and sulfide layers. The action of cobalt in both the copper sulfide and zinc oxide layers is made possible by the capability of cobalt ions to exist with variable valency (Co2+/Co3+). It is accepted that cobalt is incorporated into the zinc oxide layer early in the vulcanization process, before the onset of sulfidation. This is inferred from depth profiles that show the distribution of cobalt in the copper sulfide, zinc sulfide, and zinc oxide layers with the peak concentration just into the zinc oxide layer and penetrating to some depth. The maximum in the zinc sulfide concentration occurs in this region and so cobalt is associated with this sulfide phase. During sulfidation, cobalt will be incorporated into the outer copper sulfide layer while it grows, as cobalt sulfide, with the cobalt concentration reducing toward the surface. As it is incorporated, cobalt will lower the defect density of copper sulfide with a concomitant reduction in the diffusion rate of copper and sulfur ions through the copper sulfide layer.
0 Ferromagnetism for Spintronics Application
Published in Ram K. Gupta, Sanjay R. Mishra, Tuan Anh Nguyen, Fundamentals of Low Dimensional Magnets, 2023
Ravi Trivedi, Brahmananda Chakroborty
TM and RE have unpaired twists that associate with the host semiconductor through trade components and make the semiconductor magnetic [10]. Such semiconductors are called dilute magnetic semiconductors. Practical utilization of 2D attraction will probably require room temperature activity, air steadiness, and (for magnetic semiconductors) the capacity to accomplish ideal doping levels without dopant collection. To conquer these issues, Zhang Fu et al. [12] proposed a DMS by vanadium-doped tungsten disulfide monolayer utilizing a dependable single-step film sulfidation technique. Interest in DMSs – for the most part, dilute magnetic oxides (DMOs) or dilute magnetic semiconductor oxides (DMSOs) – has been quickly expanding because of their possible application in spintronics gadgets. DMS can be shaped by adding magnetic pollutions at exceptionally low fixations to the host cross-section, without changing the grid that arose out of the subsequent materials, for many current gadgets, e.g., cutting-edge spintronics-based multifunctional gadgets, due to the presence of ferromagnetism above room temperature [11–13]. Double oxide semiconductors, SnO2, show a rutile structure, while TiO2 has both a rutile and anatase structure. Hexagonal ZnO has a wurtzite design, and all are inherently diamagnetic.
Nanostructured Photocatalytic Materials for Water Purification
Published in Maulin P. Shah, Sweta Parimita Bera, Günay Yıldız Töre, Advanced Oxidation Processes for Wastewater Treatment, 2022
Jennyffer Martinez Quimbayo, Satu Ojala, Samuli Urpelainen, Mika Huuhtanen, Wei Cao, Marko Huttula, Riitta L. Keiski
Depending on the type of photocatalysts, some methods are more common than others. For metal oxide photocatalysts, solvothermal or hydrothermal synthesis and sol-gel synthesis are the most common methods used. For metal sulfide photocatalysts, in addition to the previous methods, precipitation and impregnation-sulfidation synthesis are used. For carbon materials, other methods available include the hummers method and thermal polymerization (Kahng, 2020). For the metal organic frameworks, slow evaporation, microwave-assisted synthesis and electrochemical synthesis also exist (Bedia, 2019). The next paragraphs will describe some of the most common methods of synthesis that are used for photocatalyst preparation.
Hydrotreatment of jatropha oil over noble metal catalysts
Published in Chemical Engineering Communications, 2019
Shailesh J. Patil, Prakash D. Vaidya
Thus far, tailored Ni–Mo and Co–Mo catalysts have been widely used for the hydrotreatment of jatropha oil (Liu et al., 2009, 2011, 2012a, 2012b; Kumar et al., 2010; Gong et al., 2012; Sharma et al., 2012; Satyarthi et al., 2014). While the performance of these catalysts is encouraging, their application necessitates pretreatment by sulfidation to maintain high activity, e.g., by passing H2S over the catalyst (Knothe, 2010) and by adding sulfur-bearing compounds to the feed (Kumar et al., 2010; Sotelo-Boyas et al., 2011). H2S released during sulfidation is harmful. Also, sulfur is leached out and the catalyst is deactivated after prolonged use (Liu et al., 2012c). Besides, traces of sulfur in the product may spoil diesel quality. Therefore, it is desirable to use catalysts that eliminate these problems. A potential alternative is to use noble metals, which are active for hydrotreatment, even without pretreatment by sulfidation.