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Title: Effects of reaction time and citric acid contents on the morphologies of BaCO{sub 3} via PVP-assisted method

Abstract

BaCO{sub 3} with different morphologies, such as dumbbell-like, pillar-like, peanut-like and ellipsoid-like have been successfully synthesized using citric acid (CA) as chelating ligand via a simple polyvinylpyrrolidone (PVP)-assisted method. The effects of the pH of the starting solutions, reaction time and the molar ratio of CA/Ba{sup 2+} on the morphologies of BaCO{sub 3} were investigated. X-ray diffraction (XRD), transmission electron microscope (TEM) and the infrared (IR) spectrum of the sample are used to characterize the obtained products.

Authors:
; ;  [1];  [2]
  1. Department of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China)
  2. Department of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China), E-mail: Sunwd843@nenu.edu.cn
Publication Date:
OSTI Identifier:
21143986
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 43; Journal Issue: 5; Other Information: DOI: 10.1016/j.materresbull.2007.06.013; PII: S0025-5408(07)00249-8; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION SPECTROSCOPY; BARIUM CARBONATES; BARIUM IONS; CHELATING AGENTS; CITRIC ACID; CRYSTAL GROWTH; CRYSTAL STRUCTURE; INFRARED SPECTRA; LIGANDS; MORPHOLOGY; PVP; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Lv Sa, Sheng Jie, Zhang Shuang, and Sun Wendong. Effects of reaction time and citric acid contents on the morphologies of BaCO{sub 3} via PVP-assisted method. United States: N. p., 2008. Web. doi:10.1016/j.materresbull.2007.06.013.
Lv Sa, Sheng Jie, Zhang Shuang, & Sun Wendong. Effects of reaction time and citric acid contents on the morphologies of BaCO{sub 3} via PVP-assisted method. United States. doi:10.1016/j.materresbull.2007.06.013.
Lv Sa, Sheng Jie, Zhang Shuang, and Sun Wendong. Tue . "Effects of reaction time and citric acid contents on the morphologies of BaCO{sub 3} via PVP-assisted method". United States. doi:10.1016/j.materresbull.2007.06.013.
@article{osti_21143986,
title = {Effects of reaction time and citric acid contents on the morphologies of BaCO{sub 3} via PVP-assisted method},
author = {Lv Sa and Sheng Jie and Zhang Shuang and Sun Wendong},
abstractNote = {BaCO{sub 3} with different morphologies, such as dumbbell-like, pillar-like, peanut-like and ellipsoid-like have been successfully synthesized using citric acid (CA) as chelating ligand via a simple polyvinylpyrrolidone (PVP)-assisted method. The effects of the pH of the starting solutions, reaction time and the molar ratio of CA/Ba{sup 2+} on the morphologies of BaCO{sub 3} were investigated. X-ray diffraction (XRD), transmission electron microscope (TEM) and the infrared (IR) spectrum of the sample are used to characterize the obtained products.},
doi = {10.1016/j.materresbull.2007.06.013},
journal = {Materials Research Bulletin},
number = 5,
volume = 43,
place = {United States},
year = {Tue May 06 00:00:00 EDT 2008},
month = {Tue May 06 00:00:00 EDT 2008}
}
  • Graphical abstract: Display Omitted Highlights: ► WO{sub 3} nanoparticles were synthesized by a simple citric acid-assisted precipitation. ► WO{sub 3} photocatalyst was able to the partial mineralization of rhB, IC and MO. ► WO{sub 3} can be considered as a photocatalyst active under visible light irradiation. -- Abstract: WO{sub 3} nanoparticles were synthesized by citric acid-assisted precipitation method using a 1:1.5 molar ratio of ammonium paratungstate hydrate (H{sub 42}N{sub 10}O{sub 42}W{sub 12}·xH{sub 2}O):citric acid (C{sub 6}H{sub 8}O{sub 7}). The formation of monoclinic crystal structure of WO{sub 3} at different temperatures was confirmed by X-ray powder diffraction (XRD). The characterization ofmore » the samples synthesized was complemented by transmission electron microscopy (TEM), Brunauer–Emmitt–Teller surface area (BET) and diffuse reflectance spectroscopy (DRS). According to the thermal treatment followed during the synthesis of WO{sub 3}, the morphology of the nanoparticles formed was characterized by rectangular and ovoid shapes. The photocatalytic activity of WO{sub 3} obtained under different experimental conditions was evaluated in the degradation of rhodamine B (rhB), indigo carmine (IC), methyl orange (MO), and Congo red (CR) in aqueous solution under UV and UV–vis radiation. The highest photocatalytic activity was observed in the sample obtained by thermal treatment at 700 °C. In general, the sequence of degradation of the organic dyes was: indigo carmine (IC) > rhodamine B (rhB) > methyl orange (MO) > Congo red (CR). The mineralization degree of organic dyes by WO{sub 3} photocatalysts was determined by total organic carbon analysis (TOC) reaching percentages of mineralization of 82% (rhB), 85% (IC), 28% (MO), and 7% (CR) for 96 h of lamp irradiation.« less
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  • Graphical abstract: A simple solvothermal method for the synthesis of flower-like SrCO{sub 3}:Tb{sup 3+} phosphors with the assistance of polyvinylpyrrolidone (PVP, K30). Highlights: Black-Right-Pointing-Pointer Well-crystallized flower-like SrCO{sub 3}:Tb{sup 3+} phosphors could be easily prepared by a simple solvothermal method with the assistance of polyvinylpyrrolidone (PVP). Black-Right-Pointing-Pointer The amount of PVP and the reaction time have a strong effect on controlling the morphology and optical properties of SrCO{sub 3}:Tb{sup 3+} particles. Black-Right-Pointing-Pointer The main synthesizing process and the growth mechanism for the formation of final samples were proposed. -- Abstract: Well-crystallized flower-like SrCO{sub 3}:Tb{sup 3+} phosphors have been synthesized by anmore » inexpensive and friendly solvothermal process using polyvinylpyrrolidone (PVP, K30) as an additive without further annealing treatment. X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), and field emission scanning electron microscopy (FESEM) as well as photoluminescence spectroscopy (PL) were used to characterize the resulting samples. The amount of PVP and the reaction time have strong effect on the morphology of the SrCO{sub 3}:Tb{sup 3+} particles. The results of XRD confirm the formation of a well-crystallized SrCO{sub 3} phase with an orthorhombic structure. The possible formation mechanism for flower-like SrCO{sub 3}:Tb{sup 3+} phosphor is proposed. The SrCO{sub 3}:Tb{sup 3+} phosphors show the characteristic {sup 5}D{sub 4}-{sup 7}F{sub J} (J = 6, 5, 4, 3) emission lines with green emission {sup 5}D{sub 4}-{sup 7}F{sub 5} (544 nm) as the most prominent group under ultraviolet excitation.« less
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