title: Guanidine sulfate-assisted synthesis of hexagonal WO3 nanoparticles with enhanced adsorption properties.
abstract: Large surface area hexagonal phase WO3 (h-WO3) nanowires were synthesized by a hydrothermal route with the assistance of C2H12N6O4S. They were characterized by XRD, SEM, TEM, BET, FT-IR and XPS. It is shown that C2H12N6O4S not only acts as a stabilizer to facilitate the generation of a metastable hexagonal phase, but also functions as a structure directing agent to assist the construction of nanowires. The obtained h-WO3 possesses a large specific surface area and numerous adsorption functional groups such as -OH groups. These characteristics result in an excellent adsorption performance for the removal of strontium from acidic aqueous solutions. A maximum adsorption capacity of 52.93 mg g(-1) was achieved on the h-WO3 prepared in the presence of C2H12N6O4S. This value is almost two times higher than that of bare h-WO3 (no C2H12N6O4S). The effects of pH, contact time, initial Sr(2+) concentration and ion strength on Sr(2+) removal from the solution by h-WO3 were systematically investigated. The adsorption mechanism involving the combination of electrostatic attraction and ion exchange for the adsorption of Sr(2+) is proposed. Based on our results, h-WO3 with high adsorption capacity and good surface characteristics exhibits great potential for the removal of Sr(2+) from radioactive wastewater.
authors: Institute of Nuclear Chemistry and Physics, China Academy of Engineering Physics, Mianyang, Sichuan, China.
authors: Wanjun
authors: W
authors: Mu
authors: Mei
authors: M
authors: Li
authors: Xingliang
authors: X
authors: Li
authors: Zongping
authors: Z
authors: Ma
authors: Rui
authors: R
authors: Zhang
authors: Qianhong
authors: Q
authors: Yu
authors: Kai
authors: K
authors: Lv
authors: Xiang
authors: X
authors: Xie
authors: Jiaheng
authors: J
authors: He
authors: Hongyuan
authors: H
authors: Wei
authors: Yuan
authors: Y
authors: Jian