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Configuration Optimizations and Photophysics Simulations of Single-Wall Nanotubes of Carbon, Silicon-Carbide, and Carbon-Nitride
Published in Sarhan M. Musa, ®, 2018
W.-D. Cheng, C.-S. Lin, G.-L. Chai, S.-P. Huang
Additionally, the properties of nanotubes can be changed by doping with foreign atoms, which provides opportunities to tune their properties and optimize their appliances. Carbon-nitride nanotubes (CNNTs) may have improved applications compared with traditional CNTs due to their high specific surface area and polar C–N bonds at the surface. Theoretical studies have indicated that CNNTs with CN or C3N4 stoichiometry may exist [39]. Thus, many research groups made efforts to synthesize CNNTs A lot of N-doped CNTs have been synthesized by various methods [40,41], and it was found that N-doped CNTs have many novel properties such as electrocatalytic activity [42,43], magnetism [44], and field emission [45] and can be used as catalyst supporter [46].However, both experimental and theoretical studies indicated that the doped concentration of the N in the CNTs is limited (no more than 10%). Accordingly, it is impossible to synthesize CNNTs through doping method. Guo and coworkers [47] reported that the syntheses of C3N4 nanotubes are via a benzene-thermal process without the use of any catalyst or template, and Minsik and coworkers reported that C3N4 nanostructures were synthesized by condensing cyana-mide (CN-NH2) using colloidal silica as a template; they used the C3N4 nanostructures as supporter of Pt-Ru alloy catalyst [48]. Porous nanotubes with CN stoichiometry were synthesized by Cao et al. [49] through the reaction of cyanuric chloride (C3N3Cl3) with sodium at 230°C using NiCl2 as catalyst. However, the structures of synthesized CNNTs are different from that of the CNNTs predicted previously [39]. By using the same method, Li et al. synthesized three kinds of CN architectures: nanotube bundles, aligned nanorib-bons, and microspheres [50]. The synthesized CNNTs with the stoichiometry of CN are multiwall nanotubes with diameters ranging from 50 to 100 nm and lengths of several micrometers. The C and N atoms in CNNTs show the character of sp2 hybridization, which indicate the graphitic structures in CNNTs. Generally, the CNNTs always show open ends [49].The UV-vis absorption spectra of the CNNTs indicate that there is strong absorption around 260–280 nm, which may be due to the π → π*electronic transition in the aromatic 1,3,5-triazine units within the CNNTs [50].Theoretically, Jose et al. investigated the C3N4 nanotubes systematically recently [51]. There are also reports on the studies of optical or thermodynamic properties of nanotubes with other N:C stoichiometry [52,53]. However, there are not theoretical and experimental studies addressing the optical properties of SiCNTs and CNNTs. Therefore, precise predictions for the fundamental optical properties of SiCNTs and CNNTs are strongly desirable. In these respective subjects, we investigate the optical properties of the zigzag (n, 0), armchair (n, n), and chiral (n, m) SiCNTs, and of single-walled CNNTs built from triazine units differing in chirality and diameter size by using first-principles calculations.
Synthesis and characterization of novel fluorescent reactive dyes for dyeing of cotton fabrics
Published in The Journal of The Textile Institute, 2022
Maral Pishgar, Kamaladin Gharanjig, Mohammad Esmail Yazdanshenas, Khosro Farizadeh, AboSaeed Rashidi
There are many articles based on fluorescein and cyanuric chloride that are used in electrochemical devices, sensors, and papers as non-textile applications to the best of our knowledge (Ge et al., 2015; Guzel et al., 2018). However, there is not a wide range of hues of these compounds for textile usages. Therefore, we reported synthesis, characterization, absorption, and emission properties of two novel fluorescent reactive dyes due to the fluorescein as an eco-friendly (Baatout et al., 2019), inexpensive, typical, and water-soluble fluorophore to dye the cotton fabrics. It is essential to substitute some reactive groups such as cyanuric chloride and vinylsulfone on stilbene and fluorescein to react with the hydroxyl groups of cotton. We used the cyanuric chloride with stilbene in D1, which included the monochlorotriazine reactive group. Also, we used cyanuric chloride and vinylsulfone to synthesis a bifunctional reactive dye in D2. Moreover, these dyes are used to dye cotton fabric, and their color parameters are investigated.
Recent advancements in the mesogens comprising of 1,3,5-triazine core moiety
Published in Liquid Crystals Reviews, 2019
In this review article, we shed light on the synthetic aspect, mesomorphic behaviors, electro-optical nature, and implementation of mesogens comprising of 1,3,5-triazine unit that has been reported in the last five years. Most of the 1,3,5-triazine-based compounds exhibited hexagonal columnar mesophases with high thermal stabilities. Also, most of the synthetic protocols use cyanuric chloride as a starting material for the synthesis of 1,3,5-triazine-based compounds. In one of the synthetic protocol, triazine derivatives were synthesized using microwave condition and the work is found to be excellent in terms of green chemistry point of view. However, one of the big challenges in near future is to synthesize these molecules in the greener way i.e. using ionic liquids, ultra-sonication, etc. Furthermore, the fusion of mesomorphic and aggregation-induced emission with better charge carrier mobility and long-range ordering properties in the materials may make these materials an excellent contender for optoelectronic applications. Nowadays, one of the prime objective of the researcher is to develop new generation materials such as eco-friendly organic semiconductors, organic lasers, etc. In this context, triazine-based discoid molecules would fulfill such objectives in the near future. Also, a tremendous research needs to be done on triazine moieties not only for the enhancement of their device performances but also for the social benefits. Comprehensively, this review shows the art and potentiality of synthetic chemistry in the tuning of the physical behaviors of triazine-based compounds. We anticipate that this present review would surely assist the researchers to further investigate or develop new triazine-based inspiring works starting even from the correlation of structure-mesophase to structure-device performance.