دانلود رایگان مقاله لاتین سنتز نانوذرات اکسید اسپینل کبالت از سایت الزویر
عنوان فارسی مقاله:
سنتز نانوذرات اکسید اسپینل کبالت با استفاده از روش پیش پلیمری اصلاح شده
عنوان انگلیسی مقاله:
Synthesis of spinel cobalt oxide nanoparticles using a modified polymeric precursor method
سال انتشار : 2016
برای دانلود رایگان مقاله سنتز نانوذرات اکسید اسپینل کبالت اینجا کلیک نمایید.
مقدمه انگلیسی مقاله:
1. Introduction
Spinel cobalt oxide (Co3O4) is a material of scientific and technological interest because of its various properties, as well as the fact that it is a magnetic p-type semiconductor with two bandgaps of 2.0 eV and 1.46 eV [1], which interacts in the visible electromagnetic spectrum (absorption and emission) [2,3]. These characteristics make Co3O4 suitable for several applications, such as magnetic storage devices [2], electrochemical catalysis and photocatalysis [3–5], improvement of electrode capacity and cycling stability in lithium-ion batteries [2,6,7], electrochemical sensors [4,6], precursors for solid-state synthesis [8], supercapacitors [9,10] and nano- fluid coolants [11]. Cobalt presents two main oxidation states: +II and +III. These two valences enable cobalt to form the following oxides: CoO, Co2O3 (which exists in the hydrated form), and the more common spinel-type Co3O4 (composed of cobalt in +II and +III valences, CoOCo2O3) [12]. However, because of the polyvalent states of cobalt ion, control of the atmosphere is essential to produce the desired cobalt oxide, while the most suitable synthesis technique must be chosen and conditions controlled to obtain nanoparticles. In view of the above, researchers have attempted to synthesize cobalt oxide nanoparticles by different methods, such as hydrothermal [1,2], soft chemical method [3,5,11], direct thermal decomposition [6,11], polymer-based synthesis [7,8,13], plasma spray pyrolysis [9], solvothermal synthesis [14], microwave assisted synthesis [10,15], etc. Nonetheless, these techniques have disadvantages, such as long synthesis time, sometimes more than 20 h, and require the use of complex equipment or unusual reactants. The polymeric precursor method has undergone modifications to make it faster. The complexation of polyacrylate and metal ions in water, followed by thermal decomposition, leads to the synthesis of several oxides with very fine primary particles, such as zirconia, alumina, yttrium, lead and barium titanates [16], and cerium [17]. Recently, Gunnewiek et al. [18] performed rapid synthesis of very fine chromium oxide nanoparticles. Although this technique is very useful and fast, few studies have focused on the use of an aqueous complexation of polyacrylate to synthesize metal oxide nanoparticles. This technique uses simple equipment, aqueous solutions and very common reactants such as ammonium polyacrylate, which is widely employed as a dispersant in ceramic suspensions. In this study, a rapid, efficient and simple synthesis technique was used based on a modified polymeric precursor method. Pure spinel-type cobalt oxide nanoparticles were easily fastsynthesized in only 6–7 h. The technique consists in a waterbased complexation reaction between polyacrylic anions and cobalt cations, which takes only ten minutes, followed by freeze drying and rapid thermal decomposition at a relatively low temperature, resulting in highly crystallized nanoparticles. In addition, the optimal condition of thermal decomposition temperature was determined and the nanoparticles were characterized.
برای دانلود رایگان مقاله سنتز نانوذرات اکسید اسپینل کبالت اینجا کلیک نمایید.
کلمات کلیدی:
Phase and composition controllable synthesis of cobalt manganese ... https://www.nature.com › Nature Communications › Articles by C Li - 2015 - Cited by 88 - Related articles Jun 4, 2015 - It is challenging to synthesize cobalt manganese spinels with controlled ... Phase and composition controllable synthesis of cobalt manganese spinel nanoparticles ... Moreover, for mixed-metal oxide spinels (for example, ... [PDF]Chemical synthesis of cobalt oxide synthesis of cobalt oxide (Co3O4 ... www.isca.in/rjcs/Archives/v7/i1/9.ISCA-RJCS-2016-055.pdf Dec 26, 2016 - amorphous structure of Co3O4 nanoparticles was found. Co3O4 nanoparticles ... et al.10 reported synthesis of Co3O4 nanoparticles at 750 using sol-gel ..... #Spinel-Type Cobalt Oxide (Co3O4) Nanoparticles from the mer-Co. Covalent Hybrid of Spinel Manganese–Cobalt Oxide and Graphene ... pubs.acs.org/doi/abs/10.1021/ja210924t by Y Liang - 2012 - Cited by 622 - Related articles Jan 23, 2012 - Covalent Hybrid of Spinel Manganese–Cobalt Oxide and Graphene as ... results in covalent coupling between spinel oxide nanoparticles and ... C–O and C–N bonding in the N-rmGO sheet, suggesting the formation of ... [PDF]Oxalate-Assisted Synthesis of Nano Cobalt Oxide - USC www.usc.es/congresos/ecsoc/17/files/A/a015/index.pdf by F Manteghi - Related articles The spinel cobalt oxide Co3O4 is a magnetic semiconductor and widely used ... have also been used for the synthesis of spinel Co3O4 nanoparticles such as ... Strategies for Synthesizing Conductive Spinel Cobalt Oxide ... jes.ecsdl.org/content/159/12/A1934.figures-only Strategies for Synthesizing Conductive Spinel Cobalt Oxide Nanoparticles for ... NaOH (spinelNaOH), (c) the as prepared-material, synthesized in ternary (K,Na ... Searches related to Synthesis of spinel cobalt oxide nanoparticles synthesis of cobalt oxide nanoparticles by sol gel method preparation of cobalt oxide nanoparticles cobalt oxide nanoparticles pdf cobalt oxide nanoparticles applications
