Lin DY, Hsu HP, Wang CW, Chen SW, Shih YT, Hwang SB, Sitarek P. Temperature-Dependent Absorption of Ternary HfS
2-xSe
x 2D Layered Semiconductors.
MATERIALS (BASEL, SWITZERLAND) 2022;
15:6304. [PMID:
36143616 PMCID:
PMC9502516 DOI:
10.3390/ma15186304]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/27/2022] [Accepted: 09/07/2022] [Indexed: 06/16/2023]
Abstract
In this study, we present the investigation of optical properties on a series of HfS2-xSex crystals with different Se compositions x changing from 0 to 2. We used the chemical-vapor transport method to grow these layered ternary compound semiconductors in bulk form. Their lattice constants and crystal properties were characterized by X-ray diffraction, high-resolution transmission electron microscopy, and Raman spectroscopy. We have performed absorption spectroscopies to determine their optical band-gap energies, which started from 2.012 eV with x = 0, and gradually shifts to 1.219 eV for x = 2. Furthermore, we measured the absorption spectroscopies at different temperatures in the range of 20-300 K to identify the temperature dependence of band-gap energies. The band-gap energies of HfS2-xSex were determined from the linear extrapolation method. We have noticed that the band-gap energy may be continuously tuned to the required energy by manipulating the ratio of S and Se. The parameters that describe the temperature influence on the band-gap energy are evaluated and discussed.
Collapse