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91.
It is well established that the excessive and uncontrolled use of fossil fuels and organic chemicals have put a risk to the earth‘s environment and the life that sustains within it. Carbon-free, sustainable, alternative energy technologies have therefore become the prime focus of current research. Smart inorganic materials have emerged as the potential solution to suffice energy needs and remediate the organic pollutants discharged to the environment. One such promising, versatile material is FeCo2O4 which has gained immense research interest in the present decade due to its high efficiency and performance in energy and environmental applications. Innovative material design strategies involving the interplay of nanostructured morphology, chemical composition, redox surface states, and defect engineering have significantly enhanced both electrochemical and catalytic properties of FeCo2O4. Therefore, this review article aims to provide the first-ever comprehensive account of the latest research and developments in design-synthesis strategies, characterization techniques, and applications of nanostructured FeCo2O4 and its composites in various electrochemical as well as catalytic applications. A detailed account of the nanostructured FeCo2O4 and its composites in various energy storage and conversion devices such as supercapacitors (SCs), batteries, and fuel cells has been presented. Furthermore, a special section has been devoted to highlight the role of FeCo2O4 in enhancing the sluggish reaction kinetics of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in water splitting application. This review also highlights the role of nanostructured FeCo2O4 in photocatalytic waste water treatment, gas sensing, and dual-phase membrane technologies wherein FeCo2O4 has demonstrated promising performance. 相似文献
92.
Chandrashekhar P. Pathak Mahendra J. Patni Gaddam N. Babu 《Journal of polymer science. Part A, Polymer chemistry》1988,26(2):503-510
Poly(2-chloroethyl α-chloroacrylate) was synthesized by radical initiation, and its microstructure was evaluated using carbon-13 NMR. Methyl methacrylate (M1) and 2-chloroethyl α-chloroacrylate (M2) were copolymerized in toluene at 55°C using azobisisobutyronitrile as initiator. The reactivity ratios are 0.37 ± 0.28 and 1.21 ± 2.26, The thermal properties of these copolymers have also been reported. 相似文献
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94.
Sandeep Ghumaan Biprajit Sarkar Mahendra P. Patil Jan Fiedler Raghavan B. Sunoj Wolfgang Kaim Goutam Kumar Lahiri 《Polyhedron》2007
The complexes (μ3-L1/L2)[Ru(acac)2]3, acac− = 2,4-pentanedionato, L1 = 2,3,8,9,14,15-hexachlorodiquinoxalino[2,3-a:2′,3′-c]phenazine and L2 = 2,3,8,9,14,15- hexamethyldiquinoxalino[2,3-a:2′,3′-c]phenazine, undergo stepwise one-electron oxidation involving a total of three electrons and stepwise one-electron reduction with three (L2) or four electrons (L1). All reversibly accessible states were characterized by UV–Vis–NIR spectroelectrochemistry. Oxidation leads to mixed-valent intermediates {(μ3-L)[Ru(acac)2]3}+ and {(μ3-L)[Ru(acac)2]3}2+ of which the RuIIIRuIIRuII combinations exhibit higher comproportionation constants Kc than the RuIIIRuIIIRuII states – in contrast to a previous report for the unsubstituted parent systems {(μ3-L3)[Ru(acac)2]3}+/2+, L3 = diquinoxalino[2,3-a:2′,3′-c]phenazine. No conspicuous inter-valence charge transfer absorptions were observed for the mixed-valent intermediates in the visible to near-infrared regions. The monocations and monoanions were characterized by EPR spectroscopy, revealing rhombic ruthenium(III) type signals for the former. Electron addition produces ruthenium(II) complexes of the reduced forms of the ligands L, a high resolution EPR spectrum with 14N and 35,37Cl hyperfine coupling and negligible g anisotropy was found for {(μ3-L1)[Ru(acac)2]3}−. DFT calculations of (μ3-L1)[Ru(acac)2]3 confirm several ligand-centered low-lying unoccupied MOs for reduction and several metal-based high-lying occupied MOs for electron withdrawal, resulting in low-energy metal-to-ligand charge transfer (MLCT) transitions. 相似文献
95.
Liu J Yang Q Kapoor MP Setoyama N Inagaki S Yang J Zhang L 《The journal of physical chemistry. B》2005,109(25):12250-12256
The surfactant assistant syntheses of sulfonic acid functionalized periodic mesoporous organosilicas with large pores are reported. A one-step condensation of tetramethoxysilane (TMOS) with 1,2-bis(trimethoxysilyl)ethane (BTME) and 3-mercaptopropyltrimethoxysilane (MPTMS) in highly acidic medium was performed in the presence of triblock copolymer Pluronic P123 and inorganic salt as additive. During the condensation process, thiol (-SH) group was in situ oxidized to sulfonic acid (-SO(3)H) by hydrogen peroxide (30 wt % H(2)O(2)). X-ray diffraction studies along with nitrogen and water sorption analyses reveal the formation of stable, highly hydrophobic, and well-ordered hexagonal mesoscopic structures in a wide range of -CH(2)CH(2)- concentrations in the mesoporous framework. The resultant materials were also investigated by (29)Si MAS and (13)C CP MAS NMR, thermogravimetric analyses, UV-Raman spectroscopy, and FT-IR spectroscopy. The role of the bridged organic group on the hydrothermal stability of the mesoporous materials was established, which revealed an enhancement in hydrothermal stability of the materials with incorporation of the bridged organic groups in the network. The catalytic performance of -SO(3)H functionalized mesoporous materials was investigated in the esterification of ethanol with acetic acid, and the results demonstrate that the ethane groups incorporated in the mesoporous framework have a positive influence on the catalytic behavior of the materials. 相似文献
96.
97.
Oligomeric ultraviolet absorbers have been prepared by condensing a mixture of 2,4-dihydroxybenzophenone with formaldehyde in the presence of a concentrated solution of HCl or NaOH. The oligomers were characterized by elemental analysis, IR spectra, and TGA study. Their [Mbar]n was determined by nonaqueous conductometric titration and by VPO. Polymeric metal chelates of Cu(II), Ni(II), and Co(II) with the oligomer were prepared and characterized. 相似文献
98.
99.
100.
Mahendra Kumar Mishra 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5-6):619-625
The unsaturated esters of aleuritic acid have been prepared by the condensation method and their oligomerization has been effected by free-radical initiation. The results show that the dimers of unsaturated esters of aleuritic acid were obtained. 相似文献