Preparation and characterization of γ-La2S3 nanoparticles from thermal decomposition

Abstract

To synthesize pure γ-La 2 S 3 at lower temperature, lanthanide complex La(Et 2 S 2 CN) 3 ·phen, containing La−S bond, was chosen as the precursors to decompose. The obtained samples were characterized by X-ray power diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) with an energy dispersive spectrometer and UV-Vis diffuse reflectance spectra. The decomposition mechanism of the lanthanide complex was studied by thermogravimetric analyses (TGA). The results show that the obtained samples are cubic phase particles with sizes among 20-50 nm and the band gap is 2.97 eV, which is bigger than that of its bulk crystal. TG/DTG results indicate that La(Et 2 S 2 CN) 3 ·phen decomposed to γ-La 2 S 3 via La 4 (Et 2 S 2 CN) 3 as an intermediate product.

Research progresses of lanthanide sulfides

“…李培森等利用 La(Et 2 S 2 CN) 3 •phen 作前躯体, 在隔 绝氧气下进行热分解, 制备了-La 2 S 3 纳米材料 [106,107] , 制备的纳米粒子粒径分布均匀, 带隙宽度 2.97 eV, 这 比其体相材料的带隙更宽 [10] . 这些纳米材料可以用 作红外窗口(8-14 m)材料.…”

Preparations and characterizations of γ-Ce2S3@SiO2 pigments from precoated CeO2 with improved thermal and acid stabilities

“…In recent years, nanometre rare earth sulphides are reported due to its specic properties. Li et al 8,12 pointed out that g-La 2 S 3 nanoparticles can be prepared from La(Et 2 S 2 CN) 3 $phen though pyrolysis method. The band gap of so obtained g-La 2 S 3 is boarder than the bulk one, due to the pronounced quantum connement effect.…”