Electronic structure, optical dispersion and luminescent properties of Terbium Gallium Garnet crystal

CrystEngComm ◽  
2021 ◽  
Author(s):  
Haotian Zhang ◽  
Yuxi Gao ◽  
Ch. B Huang ◽  
Yingying Chen ◽  
Renqin Dou ◽  
...  

Terbium gallium garnet (Tb3Ga5O12, TGG) was widely investigated due to its multifunctional applications. However, the electronic structure, optical dispersion properties, band gap and luminescent mechanisms of TGG crystal are still...

2019 ◽  
Author(s):  
Victor Y. Suzuki ◽  
Luís Henrique Cardozo Amorin ◽  
Natália H. de Paula ◽  
Anderson R. Albuquerque ◽  
Julio Ricardo Sambrano ◽  
...  

<p>We report, for the first time, new insights into the nature of the band gap of <a>CuGeO<sub>3</sub> </a>(CGO) nanocrystals synthesized from a microwave-assisted hydrothermal method in the presence of citrate. To the best of our knowledge, this synthetic approach has the shortest reaction time and it works at the lowest temperatures reported in the literature for the preparation of these materials. The influence of the surfactant on the structural, electronic, optical, and photocatalytic properties of CGO nanocrystals is discussed by a combination of experimental and theoretical approaches, and that results elucidates the nature of the band gap of synthetized CGO nanocrystals. We believe that this particular strategy is one of the most critical parameters for the development of innovative applications and that result could shed some light on the emerging material design with entirely new properties.</p> <p><b> </b></p>


2021 ◽  
Vol 2 (19) ◽  
pp. 6267-6271 ◽  
Author(s):  
U. Sandhya Shenoy ◽  
D. Krishna Bhat

Extraordinary tuning of electronic structure of SnTe by Bi in the presence of Pb as a co-adjuvant dopant. Synergistic effect of resonance level, increase in the band gap, valence and conduction sub-bands convergence leads to enhanced TE performance.


2019 ◽  
Vol 7 (16) ◽  
pp. 4817-4821 ◽  
Author(s):  
U. Sandhya Shenoy ◽  
D. Krishna Bhat

Resonance states due to Bi and In co-doping, band gap enlargement, and a reduced valence-band offset in SnTe lead to a record high room-temperature ZT.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
M. Calvino ◽  
A. Trejo ◽  
M. I. Iturrios ◽  
M. C. Crisóstomo ◽  
Eliel Carvajal ◽  
...  

A study of the dependence of the electronic structure and energetic stability on the chemical surface passivation of cubic porous silicon carbide (pSiC) was performed using density functional theory (DFT) and the supercell technique. The pores were modeled by removing atoms in the [001] direction to produce a surface chemistry composed of only carbon atoms (C-phase). Changes in the electronic states of the porous structures were studied by using different passivation schemes: one with hydrogen (H) atoms and the others gradually replacing pairs of H atoms with oxygen (O) atoms, fluorine (F) atoms, and hydroxide (OH) radicals. The results indicate that the band gap behavior of the C-phase pSiC depends on the number of passivation agents (other than H) per supercell. The band gap decreased with an increasing number of F, O, or OH radical groups. Furthermore, the influence of the passivation of the pSiC on its surface relaxation and the differences in such parameters as bond lengths, bond angles, and cell volume are compared between all surfaces. The results indicate the possibility of nanostructure band gap engineering based on SiC via surface passivation agents.


2008 ◽  
Vol 2008 ◽  
pp. 1-4
Author(s):  
Dmitry E. Milovzorov

The structural, optical, and conductivity properties of silicon film deposited on cerium dioxide buffer layer were studied. The electronic structure of system consists of various defect levels inside band gap. The temperature spatial distribution plays a great role in silicon crystallization. The field destruction of crystal phase and its restoration, after annealing, were investigated.


CrystEngComm ◽  
2014 ◽  
Vol 16 (33) ◽  
pp. 7621-7625 ◽  
Author(s):  
Cody J. Gleason ◽  
Jordan M. Cox ◽  
Ian M. Walton ◽  
Jason B. Benedict

Single crystal structures, luminescent properties and electronic structure calculations of three polymorphs of the opto-electronic charge transport material 4,4′-bis(9-carbazolyl)biphenyl.


2018 ◽  
Vol 32 (09) ◽  
pp. 1850076 ◽  
Author(s):  
Irfan Ullah ◽  
Shaukat Ali Khattak ◽  
Tanveer Ahmad ◽  
Saman ◽  
Nayab Ali Ludhi

The titanium dioxide (TiO2) is synthesized by sol–gel method using titanium-tetra-iso-propoxide (TTIP) as a starting material, and deposited on the pre-cleaned glass substrate using spin coating technique at optimized parameters. Energy dispersive X-ray (EDX) spectroscopy confirms successful TiO2 growth. The optical properties concerning the transmission and absorption spectra show 85% transparency and 3.28 eV wide optical band gap for indirect transition, calculated from absorbance. The exponential behavior of absorption edge is observed and attributed to the localized states electronic transitions, curtailed in the indirect band gap of the thin film. The film reveals decreasing refractive index with increasing wavelength. The photoluminescence (PL) study ascertains that luminescent properties are due to the surface defects.


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