Comparative optical studies of Ce2S3 and Gd2S3 compounds

Abstract

A detailed comparative study of the optical properties of two rare-earth (RE) sesquisulfide compounds γ−Ce2S3 and γ−Gd2S3, shows that if the two compounds have about the same main absorption edge corresponding to band-to-band S 3p-RE 5d transitions, Ce2S3 exhibits an additional absorption band at lower energies. This band, which is ascribed to the presence of Ce 4f states at the top of the valence band, explains the difference in color between the two compounds.

The Production of UV Absorber Amorphous Cerium Sulfide Thin Film

“…Therefore, excited electrons are positioned at this energy level before switching to the conductivity band, which leads to an increase on conductivity. These results show that amorphous CeS x thin films are very useful for solar cells 5 . Transmittance (T) of CeS x thin film can be calculated by using reflectivity (R) and absorbance (A) spectra from the following expression:…”

“…(1) Figure 3 shows the plot of (αhυ) 5 . We have calculated optical band gap of crystalline cerium sulfide thin films in the range of 2.86-3.23 eV.…”

“…Optical spectrum of thin films is recorded at the wavelength range of 300-1100 nm. 5 have obtained crystalline structures for CeS x at pH > 6. They have also observed no relationship between thicknesses of the thin films and pH of the bath.…”

Structure and optical properties of - and -cerium sesquisulfide

“…Optical studies [14,15] suggest that the dark red color of ␥-Ce 2 S 3 arises from dipole-allowed excitations of electrons from 4f-states into the empty 5d-states (4f 1 5d 0 → 4f 0 5d 1 ) of the same cerium cation. The three modifications of Ce 2 S 3 have an insulating nature, as is indicated from their color.…”

Green hydrothermal synthesis and optical properties of γ-Gd2S3 nanoparticles

“…Rare earth sesquisulfides (Ln 2 S 3 ) are known to have three polymorphic forms; a, b, and c (Grzechnik et al 1999). Among these c-form is most studied for promising applications as optoelectronics (Krichevtsov et al 2001), piezoelectric transducers (Luguev et al 2000;Gadzhiev et al 2001;Grzechnik et al 2001;Qiu et al 1996;Witz et al 1996), and optical materials in IR transmission windows (Li et al 2011). For gadolinium sesquisulfides (Gd 2 S 3 ), a-phase is low-temperature phase, which transforms into c-phase with increase in temperature.…”