12036-21-4Relevant academic research and scientific papers
Synthesis, characterization and DFT investigation of new metal complexes of Ni(II), Mn(II) and VO(IV) containing N,O-donor Schiff base ligand
Aggoun, Djouhra,Messasma, Zakia,Bouzerafa, Brahim,Berenguer, Raúl,Morallon, Emilia,Ouennoughi, Yasmina,Ourari, Ali
, (2021)
In this work, a bidentate Schiff base ligand (HL) containing N and O as donor heteroatoms has been used to synthesize series of new stable metal complexes of general composition of M(L)2 with M = Mn, Ni and VO. This ligand was obtained from condensation of 2-methoxybenzylamine on 2,3-dihydroxybenzaldehyde in methanolic solutions in which its complexes were obtained by mixing the corresponding metal acetate salt and the ligand in 1:2 molar ratio. The resulting three complexes have been characterized by different analytical techniques like FT-IR, UV-Vis, mass spectroscopy, thermogravimetry and cyclic voltammetry, to identify their molecular structures and redox/electrochemical properties. Moreover, the effect of the metal on the complexes electronic properties with their reactivity has also been studied by Density Functional Theory (DFT). The stable structures were optimized by using the hybrid B3LYP/6–31 G method. The spectroscopic data obtained suggest that the metal is bonded to the ligand through the phenolic-like oxygen and the imine-type nitrogen atoms. Electronic and vibrational absorption spectra of the nickel complex was found to be of square-planar geometry while square-pyramidal and octahedral geometries have been proposed for VO(IV) and Mn(II) complexes, respectively. The thermogravimetric analyses of these complexes confirmed the presence of water molecules in their structures and thermal decomposition led to the formation of metal oxides as the latest residues. The voltammogram of the Ni(II) complex suggests the existence of quasi-reversible redox system in DMSO solution.
Synthesis of VO2 nanoparticles by a hydrothermal-assisted homogeneous precipitation approach for thermochromic applications
Li, Wenjing,Ji, Shidong,Li, Yamei,Huang, Aibin,Luo, Hongjie,Jin, Ping
, p. 13026 - 13033 (2014)
Thermochromic VO2 particles, which have potential applications in smart windows for energy saving, have been successfully prepared by a convenient route combining homogeneous precipitation and hydrothermal processes. As a result, the particle size can be easily tuned from several tens to hundreds of nanometers by controlling the initial vanadium source concentration. Lower concentration yielded large rod-like crystals, while high concentration resulted in small near-spherical nanocrystals. The decrease of the size of VO2 particles leads to an improvement in thermochromic properties, along with a wider hysteresis of the phase transition temperature. In addition, the W-doping can effectively tune the phase transition temperature (Tc) down to ambient temperature with the efficiency of about -21.3 °C per at% W in the doping range from 0 to 2.0 at% W. This journal is the Partner Organisations 2014.
Novel VO2(M)-ZnO heterostructured dandelions with combined thermochromic and photocatalytic properties for application in smart coatings
Li, Wenjing,Ji, Shidong,Sun, Guangyao,Ma, Yining,Guo, Hehe,Jin, Ping
, p. 2592 - 2600 (2016)
Hierarchical VO2(M)-ZnO dandelions with ZnO nanorods grown radially on VO2(M) nanoparticle cores have been successfully fabricated for the first time. In these dandelions, the VO2(M) NPs were prepared by a TiO2 seed-assisted hydrothermal method and the dandelion-like ZnO nanorods were formed over two steps: heteroseed-induced nucleation and the subsequent heteroepitaxial growth processes. The coupled ZnO could increase the chemical stability of VO2(M) at relatively high temperatures. In addition, the VO2(M)-ZnO composite film with decreased phase transition temperature (Tc = 62.6 °C) simultaneously displayed an enhanced visible transmission (Tvis-l = 52.2%) and solar modulating ability (ΔTsol = 9.3%) as compared with the pure VO2(M) film. Besides, the VO2(M)-ZnO dandelions also exhibited improved photocatalytic performance, likely due to the synergistic effect of the VO2(M)-ZnO heterojunction, unique dandelion-like hierarchical structure and high specific surface area. This is the first report of such a single VO2(M)-ZnO dandelions structure with energy saving and environmental protection effects that offer significant potential for creating a multifunctional smart coating.
Competing with other polyanionic cathode materials for potassium-ion batteries via fine structure design: New layered KVOPO4 with a tailored particle morphology
Liao, Jiaying,Hu, Qiao,Che, Bo,Ding, Xiang,Chen, Fei,Chen, Chunhua
, p. 15244 - 15251 (2019)
Layered materials with two-dimensional ion diffusion channels are attractive for fast kinetics in secondary batteries. However, it is a great challenge to tolerate the structure evolution and volume change during the insertion/extraction of large size K ions. Herein, we report new layered KVOPO4 (L-KVOP) with a controllable morphology prepared by a hydrothermal method. The L-KVOP electrodes exhibit advantageous K-storage performance, including a high average voltage of 3.65 V, a high capacity of 115 mA h g-1 (0.2C, 1C = 120 mA h g-1), considerable cycling stability with 86.8% capacity retention over 100 cycles (0.5C) and superior rate capability in potassium ion batteries. A high contribution of capacitive charge storage is revealed due to the fast ion diffusion in the bulk. The reversible structural evolution during K ion insertion/extraction is verified by ex situ X-ray diffraction, and the volume change is only 9.4%. Its superior rate performance and energy density make L-KVOP a promising candidate for potassium-ion batteries.
One-step construction of core/shell nanoarrays with a holey shell and exposed interfaces for overall water splitting
Lv, Qingliang,Yang, Lei,Wang, Wei,Lu, Siqi,Wang, Tianen,Cao, Lixin,Dong, Bohua
, p. 1196 - 1205 (2019)
Developing earth-abundant highly efficient water-splitting electrocatalysts has become of great importance for sustainable energy conversion processes. Herein, we construct a unique Ni foam-supported Ni3S2/VO2 core/shell nanoarray (CSN) with exposed interfaces via facile one-step growth of a holey ultrathin VO2 shell on Ni3S2 1D nanowires for highly efficient water splitting. Systematic experiments and density functional theory calculations reveal that interfaces in situ generated between the Ni3S2 core and the VO2 shell possess a low energy level d band center and less Gibbs free energy of reaction intermediates and further act as catalytic sites with enhanced intrinsic activity. Moreover, their 1D morphology, the holey shell, and the conductive substrate are beneficial for enhanced surface area and interfaces, efficient charge and mass transfer, good conductivity and structural stability. The obtained Ni3S2/VO2 CSN exhibited extremely high electrocatalytic activity and excellent durability towards electrocatalysis for the OER, HER and overall water splitting. Indeed, it requires only a very low cell voltage of 1.42, 1.45 and 1.65 V to afford current densities of 10, 20 and 100 mA cm-2, respectively, in alkaline electrolyzers, serving as one of the best water-splitting electrocatalysts to date. This work not only presents deeper understanding of intrinsic electrocatalytic properties of heterostructured catalysts with exposed interfaces but also opens new opportunities for better design of advanced electrocatalysts for water splitting.
Synthesis, molecular modeling, and docking studies of a new pyridazinone-acid hydrazone ligand, and its nano metal complexes. Spectroscopy, thermal analysis, electrical properties, DNA cleavage, antitumor, and antimicrobial activities
Abdelrahman, Maha S. A.,El-ghamry, Mosad A.,Omar, Fouz M.,Saleh, Akila A.
, (2021/12/02)
New nano Co(II), Ni(II), Cu(II), Zn(II), Fe(III) complexes, and oxovanadium(IV), dioxouranium(VI) complexes of pyridazinone-acid hydrazone ligand, DCNHP (H2L), in addition of new mixed-ligand complexes using 8-HQ/or 1,10-phen as an auxiliary ligand (L), have been synthesized and characterized by different techniques. The ligand, H2L, acted as tridentate towards the metal ions in a mono-, and bis- deprotonated form. The complexes exhibited a variety of geometrical structures including octahedral, square pyramidal, and tetrahedral configurations. The results of TGA confirmed the thermal stability of the metal complexes. The X-ray diffractograms and TEM images confirmed that the particles of the investigated compounds have been situated in nano-range with spherical and stick-shaped. Molecular modeling studies indicated that the theoretical data agree well with the experimental results. The antimicrobial activity study showed enhancement in activity of the free ligand upon complexation. The results of antitumor screening indicated that all examined compounds displayed inhibition of Hepatocellular carcinoma cell line (HepG-2) viability. The ligand, H2L, and its nano Cu(II) complex 7 displayed strong antitumor activity with IC50 = 3.80 and 3.81 μg/mL, respectively. The DNA cleavage study revealed that no ability for the screened compounds to cleavage DNA, and they may be able to induce cellular death in cancer cells through the apoptosis pathway. The docking results suggesting strong interactions of both the ligand, H2L, and its Cu(II) complex 7 with the VEGFR-2 enzyme, these interactions are very similar to that of the known hepatocellular carcinoma (HCC) inhibitor, sorafenib (Nexavar) with the target enzyme, and indicating the effective inhibition of the investigated compounds towards hepatocellular carcinoma. Moreover, the electrical conductivity study in solid-state revealed that the nano Cu(II) complex 7 displayed higher σac values than that for the free ligand, H2L, and the investigated compounds act as semiconductors.
Synthesis, characterization, potential antimicrobial, antioxidant, anticancer, DNA binding, and molecular docking activities and DFT on novel Co(II), Ni(II), VO(II), Cr(III), and La(III) Schiff base complexes
Abdalla, Ehab M.,Abdel-Rahman, Laila H.,Al-Farhan, Badriah Saad,Basha, Maram T.,Shehata, Mohamed R.
, (2021/11/01)
In this study, five novel complexes for Co(II), Ni(II), VO(II), Cr(III), and La(III) ions were synthesized from a tridentate NNO monobasic chelating Schiff base ligand, (Z)-2-((pyridin-2-ylimino)methyl)phenol (HL). Spectral and analytical tools were applied to elucidate the structural compositions of the new compounds. Then, geometry optimization was conducted for all the syntheses by the Gaussian 09 program via the density functional theory method to obtain optimal structures and the most essential parameters. Moreover, the biochemical behaviors of all the syntheses were explored based on the reactivity, which was tested against various cancer cell lines (HepG-2, MCF-7, and HCT-116). The complexes exhibited an interestingly antiproliferative potential against human cancer cell lines, and the cytotoxicities of the new complexes were arranged to follow the order: VOL > CrL > NiL > LaL > CoL > HL. The antioxidant behaviors of the complexes were studied using the DPPH assay, and VOL showed the maximum antioxidant activity, followed by LaL. The antibacterial activities of the HL ligand and its complexes were studied. Moreover, the binding nature of the complexes with calf thymus DNA (CT-DNA) was investigated based on the spectrophotometric absorption titration, viscosity, and gel electrophoresis methods. The binding ability of the complexes with CT-DNA was proposed to be just intercalation or replacement mode. The intrinsic binding constant Kb was calculated and arranged based on the following order: VOL (5.2 × 105) > CrL (3.6 × 105) > NiL (3.3 × 105) > LaL (3.0 × 105) > CoL (1.12 × 105) mol?1?dm?3. Docking investigations were performed using the receptors of COVID-19's main protease viral protein (PDB ID: 6LU7) and Escherichia coli (gram [–ve] bacteria [PDB ID: 1fj4]).
