Tin sulfide (SnS) optical properties, dielectric constants

AbstractThe highly successful PBE functional and the modified Becke–Johnson exchange potential were used to calculate the structural, electronic, and optical properties of the vacancy-ordered double perovskites A2BX6 (A = Rb, Cs; B = Sn, Pd, Pt; X = Cl, Br, and I) using the density functional theory, a first principles approach. The convex hull approach was used to check the thermodynamic stability of the compounds. The calculated parameters (lattice constants, band gap, and bond lengths) are in tune with the available experimental and theoretical results. The compounds, Rb2PdBr6 and Cs2PtI6, exhibit band gaps within the optimal range of 0.9–1.6 eV, required for the single-junction photovoltaic applications. The photovoltaic efficiency of the studied materials was assessed using the spectroscopic-limited-maximum-efficiency (SLME) metric as well as the optical properties. The ideal band gap, high dielectric constants, and optimum light absorption of these perovskites make them suitable for high performance single and multi-junction perovskite solar cells.

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Influence of Substrate Temperature on Structural and Optical Properties of Co-Evaporated Cu2SnS3/ITO Thin Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1048.189 ◽

2022 ◽

Vol 1048 ◽

pp. 189-197

Author(s):

Tippasani Srinivasa Reddy ◽

M.C. Santhosh Kumar

Keyword(s):

Thin Films ◽

Optical Properties ◽

Substrate Temperature ◽

Indium Tin Oxide ◽

Nir Spectroscopy ◽

Stoichiometric Ratio ◽

Tin Sulfide ◽

Structural And Optical Properties ◽

Average Grain Size ◽

Deposited Films

In this study report the structural and optical properties of Copper Tin Sulfide (Cu2SnS3) thin films on indium tin oxide (ITO) substrate using co-evaporation technique. High purity of copper, tin and sulfur were taken as source materials to deposit Cu2SnS3 (CTS) thin films at different substrate temperatures (200-350 °C). Further, the effect of different substrate temperature on the crystallographic, morphological and optical properties of CTS thin films was investigated. The deposited CTS thin films shows tetragonal phase with preferential orientation along (112) plane confirmed by X-ray diffraction. Micro-Raman studies reveled the formation of CTS thin films. The surface morphology, average grain size and rms values of the deposited films are examined by Scanning electron spectroscopy (SEM) and Atomic Force Microscopy (AFM). The Energy dispersive spectroscopy (EDS) shows the presence of copper, tin and sulfur with a nearly stoichiometric ratio. The optical band gap (1.76-1.63 eV) and absorption coefficient (~105 cm-1) of the films was calculated by using UV-Vis-NIR spectroscopy. The values of refractive index, extinction coefficient and permittivity of the deposited films were calculated from the optical transmittance data.

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Effect of Dopant Concentration on the Structural, Optical and Sensing Properties of (SnO2)1-x(TiO2:CuO)x Sprayed Films

Baghdad Science Journal ◽

10.21123/bsj.2019.16.2.0361 ◽

2019 ◽

Vol 16 (2) ◽

pp. 0361

Author(s):

Mahmood Et al.

Keyword(s):

Optical Properties ◽

Band Gap ◽

Energy Band ◽

Spray Pyrolysis Technique ◽

Single Crystal Silicon ◽

Dielectric Constants ◽

Energy Band Gap ◽

Crystal Silicon ◽

X Ray ◽

Regular Manner

Spray pyrolysis technique was subjected to synthesized (SnO2)1-x (TiO2: CuO) x Thin films on different substrates like glass and single crystal silicon using. The structure of the deposited films was studied using x-ray diffraction. A more pronounced diffraction peaks of SnO2 while no peaks of (CuO , TiO2 ) phase appear in the X-ray profiles by increasing of the content of (TiO2 , CuO) in the sprayed films. Mixing concentration (TiO2 , CuO) influences on the size of the crystallites of the SnO2 films ,the size of crystallites of the spray paralyzed oxide films change in regular manner by increasing of (TiO2 , CuO) amount. The effect of mixing concentration on the optical properties of the films was also investigated. The reflectance and transmittance spectra in the wavelength range (300-1100) nm were employed to determine the optical properties such as energy band gap (Eg) and refractive index (n), extinction coefficient (k) , real and imaginary parts of dielectric constants (ε1, ε2) for (SnO2)1-x(TiO2:CuO)x films. The energy band gap omit of which showed reduction from (3.65 to 2.2) eV by reducing of SnO2 amount from (100 to 70) % .The reduction of energy band gap was ascribed to the new tail states introduced in the band gap of tin oxide. The sensitivity of the prepared sensor film was determined resistance difference of the films when exposed to oxidizing gas. The data declared that the mixed SnO2 films have better sensitivity in comparison with unmixed films.

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Electronic and optical properties of zinc-blende GeC by first principles study

Modern Physics Letters B ◽

10.1142/s0217984915501031 ◽

2015 ◽

Vol 29 (20) ◽

pp. 1550103

Author(s):

Jinhui Zhai ◽

Jinguang Zhai ◽

Ajun Wan

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Dielectric Constants ◽

Electronic And Optical Properties ◽

Optical Functions ◽

Zinc Blende ◽

The Density Functional Theory ◽

Valence Bands ◽

Energy Dependent

The electronic and optical properties of zinc-blende (zb)[Formula: see text]GeC have been investigated using first principles calculations based on the density functional theory (DFT). The obtained band gap of zb–GeC is 2.30[Formula: see text]eV by means of Heyd–Scuseria–Ernzerhof (HSE) functional. We have discussed the energy-dependent optical functions including dielectric constants, refractive index, absorption, reflectivity, and energy-loss spectrum in detail. The results reveal that zb–GeC has a higher static dielectric constant compared with that of zb–SiC. The optical functions are mainly associated with the interband transitions from the occupied valence bands (VBs) Ge[Formula: see text][Formula: see text] and C[Formula: see text][Formula: see text] states to Ge[Formula: see text][Formula: see text], [Formula: see text] and C[Formula: see text][Formula: see text] states of the unoccupied conduction bands (CBs).

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