Characterization and Photocatalytic Activity of SmMnO3 Prepared by Sol-Gel Process

2017 ◽  
Vol 748 ◽  
pp. 403-407
Author(s):  
Jia Yuan Min ◽  
Long Long Yu ◽  
Pei Song Tang ◽  
Hai Feng Chen

Using samarium (III) nitrate hexahydrate, manganese nitrate and citric acid as main raw materials, the SmMnO3 gel was prepared by sol-gel process. The gel was kept at 100 °C for 24 h to get the xerogel. Then, the xerogel was respectively calcined in muffle furnace at 600 °C, 700 °C, 800 °C and 900 °C. The structure and morphology of samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopy. The UV photocatalytic activities of SmMnO3 were investigated by methyl orange which was used as simulated sewage. The results show that the pure SmMnO3 can be obtained through calcination between 700 °C and 800 °C, and the SmMnO3 have an average particle size of 80 nm. The SmMnO3 samples calcined at 700 °C and 800 °C show high photocatalytic activity for decomposition of methyl orange under UV-light irradiation. The SmMnO3 samples are consistent with first-order kinetics for the degradation of methyl orange. And the apparent rate constants are respectively k700 =0.01206 min-1and k800=0.01088 min-1.

2018 ◽  
Vol 762 ◽  
pp. 408-412
Author(s):  
Raivis Eglītis ◽  
Gundars Mežinskis

In this work two different hydrosols were used to impregnate a commercially available cotton fabric with anatase nanoparticles to give it photocatalytic activity. To increase the activity, different pre-treatment methods were applied. The nanoparticle size was determined using dynamic light scattering and x-ray diffraction and the fabrics were examined using scanning electron microscopy. Photocatalytic activity was measured using the degradation of methyl-orange while irradiating the samples with UV light. The synthesis method allowed to produce anatase with an average particle size of 32 to 37 nm depending on the synthesis method used.


2011 ◽  
Vol 287-290 ◽  
pp. 1731-1734 ◽  
Author(s):  
Han Sheng Li ◽  
Hang Xu ◽  
Shi Ying Wang ◽  
Ya Lin Pan ◽  
Qin Wu ◽  
...  

Anatase nano-titania (nano-TiO2) was prepared by using a sol-gel process mediated in reverse microemulsion combined with a solvent thermal technique. The results show that the anatase structure appears in the calcination temperature range of 400-510°C, while the transformation of anatase into rutile takes place above 510°C. The average particle size (dP) of the nano-TiO2 increases with the rise of water/Triton X-100 molar ratio (ω) but decreases with the rise of acetyl acetone/n-TBT molar ratio (p) and n-hexanol/Triton X-100 molar ratio (m). The obtained TiO2 particles with a small size have high photocatalytic activity.


2016 ◽  
Vol 852 ◽  
pp. 525-529 ◽  
Author(s):  
Ying Zhou ◽  
Zhi Yong Mei ◽  
Hai Shao Ye ◽  
Wen Wen Su ◽  
Xi Zhao ◽  
...  

Using La (NO3)3·6H2O, TiCl4 , and citric acid as the main raw materials, nanocrystalline La2Ti2O7 samples were prepared by microwave assisted method. The structure and morphology of samples were characterized by thermogravimetric and differential thermal analysis (TG-DTA), powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopy. The photocatalytic activity of La2Ti2O7 was studied for methyl orange (MO) used as simulated sewage. It was found that the single phase La2Ti2O7 could be obtained through the calcination of microwave processed La2Ti2O7 precursors at 600 °C. The resulted product had an approximate spherical shape and average grain size of 50 nm in diameter. Under UV light, the photocatalytic experiment indicated that the prepared La2Ti2O7 nanocrystalline had high photocatalytic activity for degradation of methyl orange.


2011 ◽  
Vol 279 ◽  
pp. 83-87 ◽  
Author(s):  
Pei Song Tang ◽  
He Sun ◽  
Feng Cao ◽  
Jin Tian Yang ◽  
Sheng Liang Ni ◽  
...  

The LaNiO3 nanoparticles were prepared by a sol-gel process. The LaNiO3 nanoparticles were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Vis diffuse reflectance spectroscopy (DRS). XRD and SEM demonstrate the successful synthesis of single phase perovskite LaNiO3 and an average grain size of 80 nm in diameter. It was found that the as-prepared LaNiO3 shows strong visible-light absorption with absorption onset of 545 nm, indicating a narrow optical band gap of 2.28 eV. Consequently, LaNiO3 nanoparticles show high visible-light photocatalytic activity for decomposition of methyl orange in comparison with the commercial Degussa P25. The photocatalytic experiment shows the high photocatalytic activity for the decomposition of methyl orange under visible-light irradiation, which is attributed to the strong visible-light absorption.


2021 ◽  
Author(s):  
Mahesh Gaidhane ◽  
Deepak Taikar ◽  
Pravin Gaidhane ◽  
Kalpana Nagde

Abstract Nanocrystalline α-Fe2O3 is synthesized by sol-gel technique. The prepared nanomaterial was characterized by X-ray diffraction (XRD), SEM, TEM, Fourier Transform Infrared (FTIR) spectroscopy, Vibrating Sample Magnetometry (VSM) and photoluminescence (PL) techniques. X-ray powder diffraction analysis confirmed the formation of α-Fe2O3. Electron microscopy showed spherical morphologies with an average particle size of 30-40 nm. The magnetic property of the prepared material was studied by VSM at room temperature. VSM study shows superparamagnetic nature of the synthesized nanoparticles. Photoluminescence (PL) emission spectra show intense broad emission band centered at 570 nm with 393 nm excitation indicating its usefulness for w-LED application. The CIE-chromaticity color coordinates of prepared material were calculated. The photocatalytic activity of the α-Fe2O3 nanoparticles was analyzed and the nanopowder exhibited good photocatalytic activity for the removal AO7 from its aqueous solution.


2011 ◽  
Vol 412 ◽  
pp. 271-274
Author(s):  
Ying Li ◽  
Qiang Xu ◽  
Ling Dai

In order to prepare ultrafine La3NbO7 powder, a potential material for thermal barrier coatings, the calcination process of La3NbO7 was studied in this paper.The precursor of La3NbO7 was synthesized by using a citric acid complex method. A calcination process had been systematically investigated. The reaction temperature was determined by differential scanning calorimetry (DSC). The phase composition of powders was characterized by X-ray diffraction (XRD), and the morphology was obtained by scanning electron microscope (SEM). The results revealed that the single-phase La3NbO7 powder could be successfully prepared while the calcination temperature exceeded 800°C and a better morphology could be maintained at 800°C for 4 hours. Considering all above, an optimum calcination scheme was adopted at 800°C for 4 hours. The as-prepared La3NbO7 powders had a grain size of about 50nm and an average particle size of about 300nm.


2013 ◽  
Vol 850-851 ◽  
pp. 156-159
Author(s):  
Xin Yan Wu ◽  
Wei Xiong

TiO2 nanosheets have been successfully synthesized via a simple sol-gel process. These nanostructures were characterized by transmission electron microscopy (TEM) and x-ray energy dispersive spectrometer (EDS). The sheet-shaped single-crystalline nanostructures are pure rutile-phase structure, with landscape dimension of 10-45 nm. EDS investigation confirms that the TiO2 nanosheets are only composed of Ti and O, and the atomic ration of Ti and O is close to 1:2. High photocatalytic activity might be expected for those TiO2 nanosheets due to their large surface area.


2019 ◽  
Vol 814 ◽  
pp. 487-492
Author(s):  
Xi Hao Lin ◽  
Pei Song Tang ◽  
Bei Bei Wang ◽  
Hai Qiang Tang

Using zinc acetate, glycerol alcohol and sodium hydroxide as principal raw materials, the ZnO microspheres were prepared by hydrothermal method at 200°C. The samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and diffuse reflectance spectroscopy (DRS). Using methyl orange as the degradation object, the photocatalytic activities and recycling stability of ZnO were characterized. The results show that ZnO samples are spherical and the average diameter is approximately 3-4μm. Moreover, the bandgap width is 3.1eV. Under ultraviolet light irradiation, it is testified that ZnO shows a excellent photocatalytic activity for the degradation of methyl orange. From experience, we can draw a conclusion that the ZnO samples were in line with first-order kinetics, with an apparent rate constant of 0.016min-1. At the same time, ZnO showed excellent recycling performance. Although the samples have been recycled three times, it still maintained high photocatalytic activity.


Molecules ◽  
2019 ◽  
Vol 24 (16) ◽  
pp. 2996 ◽  
Author(s):  
Jing He ◽  
Yi-en Du ◽  
Yang Bai ◽  
Jing An ◽  
Xuemei Cai ◽  
...  

Anatase/rutile mixed-phase TiO2 nanoparticles were synthesized through a simple sol-gel route with further calcination using inexpensive titanium tetrachloride as a titanium source, which effectively reduces the production cost. The structural and optical properties of the prepared materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-vis adsorption. The specific surface area was also analyzed by Brunauer–Emmett–Teller (BET) method. The anatase/rutile mixed-phase TiO2 nanocomposites containing of rod-like, cuboid, and some irregularly shaped anatase nanoparticles (exposed {101} facets) with sizes ranging from tens to more than 100 nanometers, and rod-like rutile nanoparticles (exposed {110} facets) with sizes ranging from tens to more than 100 nanometers. The photocatalytic activities of the obtained anatase/rutile mixed-phase TiO2 nanoparticles were investigated and compared by evaluating the degradation of hazardous dye methylene blue (MB) under ultraviolet light illumination. Compared to the commercial Degussa P25-TiO2, the mixed-phase TiO2 nanocomposites show better photocatalytic activity, which can be attributed to the optimal anatase to rutile ratio and the specific exposed crystal surface on the surface. The anatase/rutile TiO2 nanocomposites obtained at pH 1.0 (pH1.0-TiO2) show the best photocatalytic activity, which can be attributed to the optimal heterojunction structure, the smaller average particle size, and the presence of a specific exposed crystal surface. The enhanced photocatalytic activity makes the prepared anatase/rutile TiO2 photocatalysts a potential candidate in the removal of the organic dyes from colored wastewater.


2013 ◽  
Vol 544 ◽  
pp. 3-7 ◽  
Author(s):  
Jin Sheng Li ◽  
Xu Dong Sun ◽  
Shao Hong Liu ◽  
Di Huo ◽  
Xiao Dong Li ◽  
...  

Fine yttrium stearate powder was produced at a relatively low temperature using yttrium nitrate hexahydrate, ammonia and stearic acid as the raw materials. Dispersed Y2O3 nanopowder was synthesized by calcining the yttrium stearate. The formation mechanism of the precursor and the Y2O3 nanopowder was studied by means of XRD, TG-DTA, FT-IR, BET, FE-SEM and HR-TEM. Pure and dispersed Y2O3 nanopowder with an average particle size of 30 nm was produced by calcining the precursor at 600 °C. The particle size increases to about 60 nm with the increase of the calcination temperature to 1000 °C. In the preparation of Y2O3 from yttrium stearate, no water medium is involved, thus capillarity force and bridging of adjacent particles by hydrogen bonds can be avoided, resulting in good dispersion of the particles. The dispersed Y2O3 nanopowder prepared in this work has potential application in phosphors and transparent ceramic materials.


Sign in / Sign up

Export Citation Format

Share Document