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Journal of Rare Earths 2018年第12期36卷 1292-1298页

作者： Mohammadreza Mansournia Mahsa Orae Department of Inorganic Chemistry Faculty of chemistry University of Kashan

In this work,we present a new and fast method to obtain the single phase YFeO(YIG,cubic) and YFeO(YIP, orthorhombic) nanocrystals based on hydrothermal technique. The influence of initial Y/Fe mole ratio and calcination temperature on the nature, purity, phase structure, and morphology of the product was investigated by X-ray diffraction(XRD), Fourier-transform infrared(FT-IR) spectroscopy,energy-dispersive(EDX) X-ray spectroscopy, and field emission scanning electron microscopy(FESEM).The results show that the transformation of the as-synthesized YIG from amorphous to orthorhombic and finally to cubic phase occurs with the increase of annealing temperature. On this basis, the pure cubic phase YIG can be obtained by calcination(at 1100℃) of the precursor which is prepared using the hydrothermal treatment of mole ratio of Y:Fe = 1:1.5 exposure to an ammonia atmosphere. Also, the initial Y/Fe mole ratio of 1:1 and calcination temperature of 1000 ℃ are the optimal conditions to form single-phase nanocrystalline YIP. Further, vibrating sample magnetometry(VSM) measurements illustrate the average magnetic saturation, coercivity and remanence of 2.73 and 15.00 emu/g, 42.74 and40.02 Oe, and 1.65 and 4.30 emu/g for YIP and YIG nanocrystals, revealing their soft ferromagnetic character.

关键词： Yttrium-iron garnet Yttrium orthoferrite Ammonia atmosphere Nanoparticles Magnetic materials Phase transformation

Structure, photocatalytic and antibacterial activity study of Meso porous Ni and S co-doped TiO2 nano material under visible light irradiation

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1630-1641页

作者： K.V.Divya Lakshmi T.Siva Rao J.Swathi Padmaja I.Manga Raju M.Ravi Kumar department of inorganic and Analytical chemistry Andhra University

Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel method.The characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic and analytical techniques.The characterization results of the samples revealed that all the samples exhibited anatase phase(XRD),decreasing band gap(2.68 eV)(UV–Vis-DRS),small particle size(9.2 nm)(TEM),high surface area(142.156 m^2·g^-1)(BET),particles with spherical shape and smooth morphology(SEM);there is a frequency shift observed for co-doped sample(FT-IR)and the elemental composition electronic states and position of the doped elements(Ni and S)in the TiO2 lattice analyzed by XPS and EDX.These results supported the photocatalytic degradation of Bismarck Brown Red(BBR)achieved with in 110 min and also exhibited the antibacterial activity on Staphylococcus aureus(MTCC-3160),Pseudomonas fluorescence(MTCC-1688)under visible light irradiation.

关键词： Sol–gel Ni–S co-doped TiO2 Photocatalysis under visible light Degradation of Bismarck Brown Red Antibacterial activity

Recent trends and morphology mechanisms of rare-earth based BiFeO_(3) nano perovskites with excellent photocatalytic performances

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Journal of Rare Earths 2023年第3期41卷 331-341,I0001页

作者： Subramani Supriya Department of Inorganic Chemistry University of Chemistry and Technology PragueTechnick’a 516628Prague 6Czech Republic

The multiferroic bismuth ferrite(BiFeO_(3),denoted as BFO)semiconductors have attracted prominent recognition due to their unique physical properties and prospective industrial applications.Significant features like strong photo absorption and morphological structure play a major role in rare earth-based BFO materials.The article encapsulates the latest developments on rare-earth-based nano BFO as new class photo catalytic materials for electro-optic applications.Detailed discussion on degradation efficiencies of industrial organic dyes in ultra-violet,visible light,and near infra-red photocatalysis was carried out.The various techniques acquired to fabricate rare-earth-based BFO and the modification approaches in A-and B-site that take part in the morphology,and photo activity improvement were also detailed.This review also summarizes the existing state of research work and explains some practical ideologies of BiFeO_(3) for their future developments.Finally,this article discusses the summary and future aspects of the present challenges faced by the BFO based materials for feasible improvements.

关键词： BiFeO_(3) Photocatalysis Morphology Organic dyes Nano Rare earths

POLYROTAXANE WITH π-CONJUGATED PORPHYRIN AND POLYAZOMETHINE SYSTEMS PREPARED FROM A TYPE OF PORPHYRIN-DIALDEHYDE AND COMPLEX OF β-CYCLODEXTRIN WITH 1,4-PHENYLENEDIAMINE

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Chinese Journal of Polymer Science 2013年第1期31卷 139-147页

作者： Raziyeh Akbarzadeh Hossein Dehghani Department of Inorganic Chemistry Faculty of ChemistryUniversity of Kashan

The synthesis of 5,15-bis[4-（methoxycarbonyl）phenyl]-10,20-diphenylporphyrin （2） and its reduction to 5,15- bis[4-（hydroxymethyl）phenyl]-10,20-diphenylporphyrin （3）, and so its oxidation to provide 5,15-bis（4-formylphenyl）-10,20- diphenylporphyrin （4） are reported. The copolymer possessing β-cyclodextrin （fl-CD）, n-conjugated porphyrin and polyazomethine systems was synthesized by the polycondensation of porphyrin-dialdehyde monomer （4） and ,β- cyclodextrin/1,4-phenylenediamine complex （5）. The monomers and the copolymer were characterized by UV-Vis, ^1H-NMR and IR spectra. Furthermore, ^1H-NMR and FT-IR spectra confirmed locating the aromatic ring of 1,4-phenylenediamine molecule in the center of β-cyclodextrin cavity.

关键词： Polymer Porphyrin 1,4-Phenylenediamine Imine Cyclodextrin.

Succinate-bonded pullulan: An efficient and reusable super-sorbent for cadmium-uptake from spiked high-hardness groundwater

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Journal of Environmental Sciences 2015年第11期27卷 51-58页

作者： Azhar Abbas Muhammad Ajaz Hussain Muhammad Amin Muhammad Sher Muhammad Nawaz Tahir Wolfgang Tremel department of chemistry University of Sargodha Institute of inorganic and Analytical chemistry Johannes Guttenberg University

Chemically modified pullulan was evaluated for its sorption efficiency and selectivity to remove cadmium（Cd） from spiked high-hardness groundwater（GW）. Pullulan esterified with succinic anhydride using dimethylaminopyridine showed a fairly high degree of substitution value as confirmed by1 H NMR spectroscopy. Pullulan succinate（Pull-Suc） was converted into the sodium salt（Pull-Suc-Na）. The effect of contact time（5–200 min） and p H（2–8） on Cd-uptake by the sorbent（Pull-Suc-Na） was investigated. The sorbent showed more than 90% Cd-removal in first 15 min from distilled water（DW） and GW solution,respectively. Comparison of Pull-Suc-Na with other polysaccharidal sorbents suggested its high efficiency（DW 476.2 mg/g and GW 454.5 mg/g） and selectivity for the removal of Cd by an ion exchange mechanism, which is further supported by the negative Gibbs free energy values calculated from Langmuir isotherms. A Langmuir isotherm kinetic model provided the best fit for the sorption of Cd using Pull-Suc-Na. The sorbent showed a negligible decrease in Cd-uptake over three regeneration cycles. The thermal stability testing of the sorbents indicated that Pull-Suc-Na（sorbent） is more stable than Pull-Suc.

关键词： Adsorption Cadmium Modified pullulan Succinylation Thermal stability

One step synthesis and characterization of copper doped sulfated titania and its enhanced photocatalytic activity in visible light by degradation of methyl orange

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Chinese Journal of Chemical Engineering 2016年第4期24卷 475-483页

作者： Radha Devi Chekuri Siva Rao Tirukkovalluri department of inorganic and Analytical chemistry School of Chemistry Andhra University Visakhapatnam India

This paper reports on the synthesis of copper doped sulfated titania nano-crystalline powders with varying(2.0%–10.0%, by mass) by single step sol gel method. The synthesized photo catalyst has been characterized by employing various techniques like X-ray Diffraction(XRD), Ultraviolet–Visible Diffuse Reflection Spectroscopy(UV–Vis DRS), X-ray Photoelectron Spectroscopy(XPS), Scanning Electron Microscopy(SEM), Energy Dispersive Spectrometry(EDS), Fourier Transform Infrared Spectroscopic Studies(FT-IR), and Transmission Electron Microscopy(TEM). From the XRD and TEM results, all the samples were reported in anatase phase with reduction in particle size in the range of 7 to 12 nm. SEM indicated the change in morphology of the particles. The presence of copper in titania lattice was evidenced by XPS. From UV–Vis DRS and FT-IR studies indicated that prominent absorption shift is observed towards visible region(red shift), the entry of Cu2+into Ti O2 lattice as a substitutional dopant and SO42-ions were covalently bonded with Ti4 +on the surface of the copper doped titania respectively.The photocatalytic activity studies were investigated by considering methyl orange(MO) as dye pollutant in the presence of the visible light. The effect of various parameters like effect of dosage of the catalyst, dopant concentration, p H of the solution, and concentration of the dye was studied in detail.

关键词：二氧化钛一步合成可见光区表面掺杂甲基橙光催化降解硫酸 X射线光电子能谱

Dual-radical-based molecular anisotropy and synergy effect of semi-conductivity and valence tautomerization in a photoswitchable coordination polymer

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National Science Review 2023年第6期10卷 200-214页

作者： Jing-Wei Dai Yu-Qin Li Zhao-Yang Li Hai-Tao Zhang Carmen Herrmann Shohei Kumagai Marko Damjanovi? Markus Enders Hiroyuki Nojiri Masakazu Morimoto Norihisa Hoshino Tomoyuki Akutagawa Masahiro Yamashita State Key Laboratory of Medicinal Chemical Biology Nankai University School of Materials Science and Engineering Nankai University Institute of inorganic and Applied chemistry University of Hamburg department of chemistry Graduate School of Science Tohoku University Institute of inorganic chemistry University of Heidelberg Institute for Materials Research Tohoku University department of chemistry Rikkyo University Institute of Multidisciplinary Research for Advanced Materials (IMRAM) Tohoku University

Organic radicals are widely used as linkers or ligands to synthesize molecular magnetic materials.However,studies regarding the molecular anisotropies of radical-based magnetic materials and their multifunctionalities are rare.Herein,a photoisomerizable diarylethene ligand was used to form{[CoⅢ(3,5-DTSQ·-)(3,5-DTCat2-)]2(6F-DAE-py2)}·3CH3CN·H2O(o-1·3CH3CN·H2O,6F-DAE-py2=1,2-bis(2-methyl-5-(4-pyridyl)-3-thienyl)perfluorocyclopentene),a valence-tautomeric(VT) coordination polymer.We directly observed dual radicals for a single crystal using high-field/-frequency(～13.3 T and～360 GHz) electron paramagnetic resonance(EPR) spectroscopy along the c-axis,which was further confirmed by angle-dependent Q-band EPR spectroscopy.Moreover,a conductive anomaly close to the VT transition temperature was observed only when probes were attached at the ab plane of the single crystal,indicative of synergy between valence tautomerism and conductivity.Structural anisotropy studies and density functional theory(DFT) calculations revealed that this synergy is due to electron transfer associated with valence tautomerism.This study presents the first example of dual-radical-based molecular anisotropy and charge-transfer-induced conductive anisotropy in a photoswitchable coordination polymer.

关键词： valence tautomerization charge transfer photo switching diradical coordination polymer

Synthesis of few-layer N-doped graphene from expandable graphite with melamine and its application in supercapacitors

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Chinese Chemical Letters 2020年第2期31卷 559-564页

作者： Yunpeng Wu Xiaoyang Liu Dandan Xia Qiushi Sun Deyang Yu Shuanggan Sun Xilong Liu Yifei Teng Weige Zhang Xudong Zhao State Key Laboratory of inorganic Synthesis and Preparative chemistry College of ChemistryJilin UniversityChangchun 130012China Department of Inorganic Chemistry Shenyang Pharmaceutical UniversityBenxi 117004China

In this paper,we introduced a novel method to prepare the few-layer nitrogen-doped graphene(FNG)from expandable graphite with melamine.The super-capacitive properties of FNG were thoroughly characterized by a three-electrode system,and the results showed the FNG electrode achieved a specific capacitance as high as 83.8 mF/cm2 together with excellent cycling stability.This method could be a novel approach to combine the pseudo-capacitors and electric double layer capacitors.

关键词： Expandable graphite Graphene Nitrogen doping Supercapacitor Melamine

Preparation and Microstructural Characterization of Activated Carbon-Metal Oxide Hybrid Catalysts:New Insights into Reaction Paths

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Journal of Materials Science & Technology 2015年第8期31卷 806-814页

作者： A.Barroso-Bogeat M.Alexandre-Franco C.Fernndez-Gonzlez V.Gómez-Serrano department of Organic and inorganic chemistry Faculty of SciencesUniversity of Extremadura

In catalysis processes, activated carbon （AC） and metal oxides （MOs） are widely used either as catalysts or as catalyst supports because of their unique properties. A combination of AC and MO nanoparticles in a single hybrid material usually entails both chemical and microstructural changes, which may largely influence the potential catalytic suitability and performance of the resulting product. Here, the prepa- ration of a wide series of AC-MO hybrid catalysts is studied. Three series of such catalysts are prepared by support first of MO （Al2O3, Fe2O3, SnO2, TiO2, WO3, and ZnO） precursors on a granular AC by wet impregnation and oven-drying at 120 ℃, and by subsequent heat treatment at 200 or 850℃ in inert atmosphere. Both the chemical composition and microstructure are mainly investigated by powder X-ray diffraction. Yield and ash content are often strongly dependent on the MO precursor and heat treatment temperature, in particular for the Sn catalysts. With the temperature rise, trends are towards the transformation of metal hydroxides into metal oxides, crystallinity improvement, and occurrence of drastic composition changes, ultimately leading to the formation of metals in elemental state and even metal carbides. Reaction paths during the preparation are explored for various hybrid catalysts and new insights into them are provided.

关键词： Activated carbon Metal oxides Hybrid catalysts Preparation Microstructural characterization X-ray diffraction

纳米晶La_(1-x)Eu_xFeO_3的合成、表征及催化甲苯燃烧反应活性(英文)

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催化学报 2011年第9期32卷 1465-1468页

作者： Seyed Ali HOSSEINI Mohammad Taghi SADEGHI-SORKHANI Leila KAFI-AHMADI Abdolali ALEMI Aligholi NIAEI Dariush SALARI department of Applied chemistry Faculty of Chemistry University of Tabriz Department of Inorganic Chemistry Faculty of Chemistry University of Tabriz

Nanostructured LaFeO3 and substituted La1-xEuxFeO3 (x = 0.1, 0.15, and 0.2) perovskites were synthesized by sol-gel auto-combustion and their activities during the combustion of toluene were evaluated. The structure and physico-chemical properties of the perovskites were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and BET surface area analyses. The compounds were crystallized as a perovskite phase with an orthorhombic structure. The mean particle size of the perovskites increased with an increase in europium loading while the specific surface area decreased. Characterization data confirmed that a total insertion of Eu into LaFeO3 occurred at x ≤ 0.15. However, Eu2O3 segregation occurred to some extent especially at x >0.15. The catalytic activity of the catalysts increased substantially with an increase in Eu substitution in the evaluated range.

关键词： perovskite sol-gel europium volatile organic compounds catalytic oxidation