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Hydrothermal Synthesis and Magnetic Properties of α-Fe2O3 Polyhedrons Li Tian1,2,a, Kelong Huang1,b 1 School of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan, 410083, China 2School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China altian@hnust.edu.cn, b klhuang@mail.csu.edu.cn Keywords: Hydrothermal Synthesis, α-Fe2O3, Growth Mechanism, Magnetic Properties Abstract. α-Fe2O3 polyhedrons have been successfully synthesized via a one-pot hydrothermal process.
The structure and morphology of α-Fe2O3 polyhedrons were characterized by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques.
To date, the designing of inorganic functional materials with various morphologies and structures has attracted much attention from the researchers due to their novel properties and potential applications [2].
(G) Schematic formation process of Fe2O3 polyhedrons Reaction temperature and time play a major role in solution synthesis of many types of inorganic materials, which is a rather old topic in solid-state chemistry.
In our experiments, H2Y2- ions were selected and the concentration of H2Y2- ions was testified to have great effect on the phase and structure of the products.

The crystalline structure evidenced the dominant peak at the 300 nm thickness.
Nanostructure thin films have important properties of physics and chemistry.
These thin films are used at a microstructure, for example the slanted column structure to develop a solar cell [6], the porous structure to develop gas sensor and the light catalyst [7].
The properties of physics and chemistry can be acquired by designing different structures.
The XRD patterns showed structure of crystalline, rutile phase at plane 110 and 004.

To begin a study of the bonding between Cr and ZnO, it is first necessary to specify the structure of the ZnO surface.
We have studied the properties of Cr adsorbed on polar of ZnO surface with wurtzite structure.
One may notice that the Fermi level varies within the band gap of ZnO for different adsorption surface structures.
We would stress here that the position of the surface Fermi level is determined by the surface chemistry.
The chemistry and physics of zinc oxide surfaces, J.Progress in Surface Science, 82 (2007) 55-120

Catalysts have played a vital role in chemistry in the 20 th century.
Preparation of mesoporous-microporous hybrid structures can be a good complement to the use of nanocrystalline zeolites [10].
Another possibility is to combine framework cations that may coordinate tetrahedrally and pentahedrally, leading to new structures with very large pores.
Although their introduction in the field of catalyst chemistry and technology is rather recent, heteropolyacids are now commercially applied mainly in Japan and Russia, as efficient catalysts in several petrochemical processes [19].
Conclusion In conclusion, we believe that application of solid acid catalyst proves to be one of the most interesting and important subjects in green and sustainable chemistry.

The result of SEM demonstrated that the morphology of TiO2 is a sheet and TiO2-NiO is a rod-like structure.
N2 sorption (BET) showed a mesoporous structure and interpret specific surface areas of 19.528m2/g and 63.215 m²/g.
Results and Discussion 3.1 XRD to confirm purity and crystalline structure of as-prepared TiO2 (sc) and TiO2-NiO (sc) samples Fig. 1 XRD pattern of synthesized TiO2 (sc) and TiO2-NiO (sc) samples.
The rod-like structure with sharp edges in image 4(a) indicates that the nanostructure has good crystallinity.
Specification Name of the catalyst Name of the catalyst TiO2 TiO2-NiO Structure Mesoporous Mesoporous Composition Anatase 66%,rutile 33% Anatase 66%, rutile 33% NiO-Cubic Pore diameter 3.496 nm 4.435 nm Crystallite size 20-22nm Bandgap Bandgap(experimental) 3.1ev 2.7ev Eg- Theoretical 3.2ev 2.67ev Surface area 19.528m2/g 63.215 m²/g Pore volume 0.056 cc/g 0.088 cc/g Morphology Rodlike structure Sheet like structure 3.5 Adsorption studies and Isotherm analysis Adsorption of alizarin yellow [31, 32] on TiO2 (sc) and TiO2-NiO (sc) depends on the number of active sites.

Natural pigments have low photostability due to the nature of their molecular structures.
The conjugated structures lead the pigment molecules to be degraded quickly by the UV radiation.
Impregnating bixin into kaolinite forms more stable molecular structures which improve photostability of the bixin.
In the bixin structure, both –OH and –C=O groups play an important role in the absorption of solar radiation energy.
Ma, Dye-sensitized solar cells using 20 natural dyes as sensitizers, Journal of Photochemistry and Photobiology A: Chemistry. 219(2011) 188–194

Es'kova: Russian Journal of Applied Chemistry.
Keiko: Chemistry of Heterocyclic Compounds.
Part A: Polymer Chemistry.
Sukhoy: Glass Physics and Chemistry.
Voronkov: Russian Journal of Applied Chemistry.

Sulfonated polyphosphazene-montmorillonite hybrid composite membranes for fuel cells Min Lan He1, a, Chang Jin Zhu2,b and Chao Jun Jing3,c 1 Department of Applied Chemistry, Beijing Institute of Technology; Zhongguancun South Street, Beijing, China 2 Department of Applied Chemistry, Beijing Institute of Technology; Zhongguancun South Street, Beijing, China 3 Department of Applied Chemistry, Beijing Institute of Technology; Zhongguancun South Street, Beijing, China alongdaohui1985@163.cm, bzcj@bit.edu.cn, cjingcj@bit.edu.cn Keywords: Sulfonated polyphosphazene, Montmorillonite, Hybrid membrane, Mechanical properties, Methanol permeability.
The structure and characteristics of the obtained membranes were studied by testing their X-ray diffraction (XRD), water uptake, water swelling ratio, proton conductivity, thermal properties, methanol permeability and mechanical properties.
This may be imputable to the gallery structure of the montmorillonite, which act as robust structural boundaries, limiting the accessibility of ionic domains to water molecules.
The changes in mechanical properties of membranes made by the addition of montmorillonite could be attributed to the gallery structure in the montmorillonite which may act as a cage providing impediments to the mobility of the polymer backbone.
Dupuis: Journal of Physical Chemistry B, Vol. 111 (2007) No. 45, p. 13006

A summary of the crystallographic data and structure refinements for 1 is given in Table 1.
Results and Discussion 3.1 Crystal structure of 1.
Lehn: Supramolecular Chemistry (VCH, New York 1995)
Vögtle: Supramolecular Chemistry (Wiley Chicester 1991)
Lehn: Comprehensive Supramolecular Chemistry (Pergamum, New York 1996)

Obviously, the molecular structure of chitosan was changed by grafting.
The porous-three dimensional structure was formed on the surface of terpolymer due to its compact and uniform structure.
Guangzhou Chemical Industry Vol.38 (2010), p.128 [5] Wang Ai-qin: Chitin Chemistry (Science Publication, Beijing2008)
Applied Chemistry.
[19] Huang Qiong-Yu,Zhang Ming-Xia and Liu Fang.Applied Chemistry Jan.