Preparation of α-Ni(OH)2 with Flowerlike Hierarchical Architectures via Homogeneous Precipitation Method

2011 ◽  
Vol 284-286 ◽  
pp. 684-687
Author(s):  
Chang Yu Li ◽  
Li Li Liu ◽  
Shou Xin Liu

Without using any templates or surfactants, flowerlike α-nickel hydroxide (Ni(OH)2) was successfully synthesized by homogeneous precipitation method. The prepared products were characterized by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and N2 adsorption-desorption. The prepared Ni(OH)2 is α-phase with specific surface area of 245.0 m2/g and shows flowerlike structure with 4-6 um in diameter.

2016 ◽  
Vol 723 ◽  
pp. 444-449 ◽  
Author(s):  
Juan Chen ◽  
Zhi Liang Huang ◽  
Wen Zhao Li

The porous basic magnesium carbonate (Mg5(CO3)4(OH)2.4H2O) crystal crystallographic materials with flower-like structure were prepared successfully by homogeneous precipitation method. Magnesium chloride hexahydrate (MgCl2.6H2O) and urea (CO(NH2)2) wereused as reaction materials. The experimental equipment was held at 100°C for 8 h. Phase and morphology of the product were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The formation mechanism of the product was investigated. It was found that the CO2 bubbles acted as porous templates. The growth and gathering of the CO2 bubbles induced the growth of the MgCO3.3H2O columnar crystals. Then the dissolution of the MgCO3.3H2O and the deposition of Mg5(CO3)4(OH)2.4H2O happened simultaneously. Finally the disappearance of MgCO3.3H2O brought about the formation of the porous structure.


2015 ◽  
Vol 659 ◽  
pp. 310-314
Author(s):  
Karn Serivalsatit ◽  
Thanataon Pornpatdetaudom ◽  
Adison Saelee ◽  
Sarut Teerasoradech

A wide application of magnesium aluminate spinel powder has attracted a number of studies concerning the preparation of magnesium aluminate spinel powder. In this study, a precursor for magnesium aluminate spinel was synthesized by a homogeneous precipitation method using urea as a precipitant. The precursor and the calcined powders were characterized by X-ray diffractometry, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. After precipitation, the precursor was magnesium aluminium hydrate carbonate compound. By calcining, the precursor decomposed to MgO and an amorphous phase after calcining at 600°C. The formation of magnesium aluminate spinel via a reaction between MgO and the amorphous phase was observed after calcining over 800°C. The equiaxed magnesium aluminate spinel nanoparticles with particle size of 20-40 nm were obtained after calcining at 1100°C for 2 hours. Sinterability of the obtained magnesium aluminate spinel nanoparticles was also investigated by sintering compacts of magnesium aluminate spinel nanoparticles in the temperature interval of 1300-1650°C. Sintering temperature of 1600°C allowed the fabrication of dense magnesium aluminate spinel ceramics with relative density >95%.


2007 ◽  
Vol 353-358 ◽  
pp. 2107-2110
Author(s):  
Kun Hong Hu ◽  
Xian Guo Hu ◽  
Xiao Jun Sun ◽  
He Feng Jing ◽  
Song Zhan

Molybdenum sulfide nanoparticles were prepared via quick homogeneous precipitation method (QHPM) by the reaction between Na2MoO4 and CH3CSNH2 in the presence of sulfuric acid at 80 oC. The as-synthesized molybdenum sulfide particles were studied by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The results showed that the as-synthesized molybdenum sulfide was amorphous MoS3 nanoparticles with an average size of 40 nm. The resultant amorphous MoS3 nanoparticles were then calcined under hydrogen gas flow at a selected temperature for 50 minutes. The results of XRD, TEM, and HRTEM confirmed that the MoS2 nanoparticles with about 40 nm were prepared from the amorphous MoS3 nanoparticles at 780 oC.


2011 ◽  
Vol 335-336 ◽  
pp. 1051-1055
Author(s):  
Yan Mei ◽  
Chuan Xia ◽  
Xiao Li Chen ◽  
Zuo Ren Nie

In the system of Ce(NO3)3·6H2O and urea solution during homogeneous precipitation method, hydrothermal homogeneous precipitation coupling method and homogeneous precipitation method with additive, X-ray diffraction (XRD) and transmission electron microscope (TEM) were used to study and characterize the product structures and morphologies. The outer electron configurations and the energy conservation theory were used to analyze the reasons for stability of products and valence state change of cerium ions. The results showed that synthesis technics and additives had a great effect on the cerium ion compound valence. The products were orthorhombic Ce2O(CO3)2·H2O with Valence Ш and orthorhombic CeO(CO3)2·H2O with valence Ⅵ by using homogeneous precipitation method and hydrothermal homogeneous precipitation coupling method, respectively. If an additive (triethanolamine or triethylamine) was added into the homogeneous precipitation system, the products changed into a mixture of orthorhombic CeO(CO3)2·H2O with Valence Ⅵ and cubic CeO2 with valence Ⅳ. It showed that triethanolamine or triethylamine had strong oxidizing properties and played a catalyst role in the reaction.


2019 ◽  
Vol 56 ◽  
pp. 17-27
Author(s):  
Van Dat Doan ◽  
Van Thuan Le ◽  
Hoang Sinh Le ◽  
Dinh Hien Ta ◽  
Hoai Thuong Nguyen

In this work, nanosized calcium deficient hydroxyapatite (nCDHA) was synthesized by the precipitation method, and then utilized as an adsorbent for removal of Fe (II), Cu (II), Ni (II) and Cr (VI) ions from aqueous solutions after characterizing it by various techniques as scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and BET method. A possible structure of synthesized nCDHA was proposed. The adsorption study indicated that the adsorption equilibrium is well fitted with Langmuir isotherm model with the maximum adsorption capacities followed the order of Fe (II) > Cu (II) > Ni (II) > Cr (VI) with the values of 137.23, 128.02, 83.19 and 2.92 mg/g, respectively. The ion-exchange mechanism was dominant for the adsorption of metal ions onto nCDHA at initial metal concentrations lower than 0.01 mol/L. Along with the ion-exchange mechanism, there was an additional precipitation occurred on the surface of nCDHA in the case of Fe (II) and Cu (II) at initial concentrations higher than 0.01 mol/L.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1712
Author(s):  
Appusamy Muthukrishnaraj ◽  
Salma Ahmed Al-Zahrani ◽  
Ahmed Al Otaibi ◽  
Semmedu Selvaraj Kalaivani ◽  
Ayyar Manikandan ◽  
...  

Towards the utilization of Cu2O nanomaterial for the degradation of industrial dye pollutants such as methylene blue and methyl orange, the graphene-incorporated Cu2O nanocomposites (GCC) were developed via a precipitation method. Using Hummers method, the grapheme oxide (GO) was initially synthesized. The varying weight percentages (1–4 wt %) of GO was incorporated along with the precipitation of Cu2O catalyst. Various characterization techniques such as Fourier-transform infra-red (FT-IR), X-ray diffraction (XRD), UV–visible diffused reflectance (UV-DRS), Raman spectroscopy, thermo gravimetric analysis (TGA), energy-dispersive X-ray analysis (EDX), and electro chemical impedance (EIS) were followed for characterization. The cabbage-like morphology of the developed Cu2O and its composites were ascertained from field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HR-TEM). In addition, the growth mechanism was also proposed. The results infer that 2 wt % GO-incorporated Cu2O composites shows the highest value of degradation efficiency (97.9% and 96.1%) for MB and MO at 160 and 220 min, respectively. Further, its catalytic performance over visible region (red shift) was also enhanced to an appreciable extent, when compared with that of other samples.


2011 ◽  
Vol 236-238 ◽  
pp. 2110-2113
Author(s):  
Hong Liu ◽  
Meng Yang Wang ◽  
Wei Ran Cao

The hexagonal mesoporous silica (HMS) nano-particles were prepared in mixture of 1-butyl-3-methyl-imidazolium tetrafluoroborate (BMIM+BF4-) ionic liquid and water by a sol-gel method. The structure and morphology of obtained materials were characterized by X-ray powder diffraction (XRD), N2adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS). The influence of the amount of BMIM+BF4-was investigated. It was shown that the synthesized materials have discrete and uniform spherical morphology with the size in the range of 68-177 nm (obtained from DLS measurements), and the particle size of HMS can be controlled by varying the amount of BMIM+BF4-.


2011 ◽  
Vol 236-238 ◽  
pp. 1873-1876 ◽  
Author(s):  
Jun Jie Tao ◽  
Yun Qiang Xu ◽  
Guo Wei Zhou ◽  
Cui Cui Wu ◽  
Hong Bin Song ◽  
...  

Ordered mesoporous SBA-15 was synthesized through hydrothermal process under acidic condition. The material was characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), small-angle X-ray diffraction (SAXRD), and N2 adsorption-desorption. The results indicated that SBA-15 has 2-dimensional hexagonal p6mm mesoscopic structure and well-ordered parallel mesochannel. The as-obtained mesoporous silica was used for controlled release of water-insolube drug emodin. The loading capacity could achieve 6.64 mg/g, and the release profiles that studied in phosphate buffered saline (PBS, pH = 7.4) showed that released amount of emodin was 95.8 % after 48 h.


NANO ◽  
2013 ◽  
Vol 08 (05) ◽  
pp. 1350050
Author(s):  
MIN GUAN ◽  
HAI-PENG BI ◽  
ZUYUAN WANG ◽  
SHAOHUA BU ◽  
LING HUANG ◽  
...  

Mesoporous silicas SBA-15 are modified with β-Cyclodextrins (β-CD) by simple grafting method. β-CD functionalized SBA-15 was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), nitrogen adsorption–desorption measurements, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Furthermore, the applicability of it is investigated through studying the adsorption properties of clenbuterol. It showed better adsorption capacities of clenbuterol than pure SBA-15. β-CD functionalized SBA-15 material has the potential applications in the treatment of clenbuterol contamination in food and environment science.


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