Optical Properties and Interface Study of a-Si:H/a-C:H Superlattices

1986 ◽  
Vol 77 ◽  
Author(s):  
Zhang Fangqing ◽  
He Deyan ◽  
Xu Xixiang ◽  
Cui Jinzhong ◽  
Sun Guosheng ◽  
...  
Keyword(s):  
Optical Properties ◽  
Glow Discharge ◽  
Band Gap ◽  
Optical Band Gap ◽  
Blue Shift ◽  
Interface Structure ◽  
Experimental Results ◽  
Interfacial Defects ◽  
Interface Study

ABSTRACTExperimental results on a-Si:H/a-C:H superlattices, including the blue-shift of the optical band gap, the light-induced conductivity effect, the interface structure and the interfacial defects, are presented. Differences between our glow-discharge and sputter-prepared a-Si:H/a-C:H super lat t ices are described.

scholarly journals Optical properties of zinc titanate perovskite prepared by reactive RF sputtering

2017 ◽  
Vol 68 (7) ◽  
pp. 10-16 ◽  
Author(s):  
Jarmila Müllerová ◽  
Pavol Šutta ◽  
Rostislav Medlín ◽  
Marie Netrvalová ◽  
Petr Novák
Keyword(s):  
Optical Properties ◽  
Band Gap ◽  
Optical Band Gap ◽  
Rf Sputtering ◽  
Blue Shift ◽  
Optical Transmittance ◽  
Titanium Content ◽  
Zinc Titanate ◽  
Band Gap Engineering ◽  
Photocatalytic Applications

AbstractIn this paper we report results from optical transmittance spectroscopy complemented with data on structure from XRD measurements to determine optical properties of a series of ZnTiO3perovskite thin films deposited on glass by reactive magnetron co-sputtering. The members of the series differ by the titanium content that was revealed as an origin of the changes not only in structure but also in dispersive optical properties. Low porosity has been discovered and calculated using the Bruggeman effective medium approximation. An apparent blue-shift of the optical band gap energies with increasing titanium content was observed. The observed band gap engineering is a good prospective foregoptoelectronic and photocatalytic applications of ZnTiO3.

Investigation of Annealing on the Structural and Optical Properties of Chemical Bath Deposited ZnSe Quantum Dot Thin Films

2012 ◽  
Vol 229-231 ◽  
pp. 10-13
Author(s):  
Liang Yan Chen ◽  
Chao Fang
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Band Gap ◽  
Optical Band Gap ◽  
Quantum Effect ◽  
Blue Shift ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
Znse Quantum Dot ◽  
Znse Thin Films

ZnSe thin films were obtained through chemical bath deposition method. Structural and optical properties of as deposited and annealed samples were investigated by X-ray Diffraction and spectrophotometer. The as deposited thin films were in nanocrystalline, with lots of strain and a blue shift of optical band gap. After annealing, the crystal grain gained, the strain eased and optical band gap enlarged. And it suggested that annealing can ease the quantum effect of chemical bath deposited ZnSe thin films.

Blue shift in the optical band gap of amorphous Hf–In–Zn–O thin films deposited by RF sputtering

2012 ◽  
Vol 525 ◽  
pp. 172-174 ◽  
Author(s):  
Anup Thakur ◽  
Se-Jun Kang ◽  
Jae Yoon Baik ◽  
Hanbyeol Yoo ◽  
Ik-Jae Lee ◽  
...  
Keyword(s):  
Thin Films ◽  
Band Gap ◽  
Optical Band Gap ◽  
Rf Sputtering ◽  
Blue Shift

The Role of Reduced Graphene Oxide Concentration as Ablated Material on Optical Properties of Graphene Quantum Dots

2019 ◽  
Vol 948 ◽  
pp. 267-273 ◽  
Author(s):  
Fiqhri Heda Murdaka ◽  
Ahmad Kusumaatmaja ◽  
Isnaeni ◽  
Iman Santoso
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Graphene Oxide ◽  
Band Gap ◽  
Reduced Graphene Oxide ◽  
Optical Band Gap ◽  
Graphene Quantum Dots ◽  
Absorption Peak ◽  
Oxygen Defect ◽  
Reduced Graphene

We report the synthesize of Graphene Quantum Dots (GQDs) using ablation method with reduced Graphene Oxide (rGO) solution as a starting material. We have varied the concentration of rGO as following: 0.5, 2, 5 mg/ml and then have ablated them using 800 nm Ti-Sapphire femtosecond laser to obtain GQDs. From the UV-Vis data, we observed that the more concentration of rGO is being ablated, the more secondary absorption peak at 255.1 nm appeared. This secondary absorption peak is a characteristic of n-π* bonding due to the presence of oxygen defect which occurs as a result of the interaction between the laser and the water in rGO solution. We conclude that the population of oxigen defect in GQDs is increasing, following the increase of rGO concentration and could alter the optical properties of GQD. On the other hand, using Tauc’s plot, we confirm that the increase of rGO concentration as the ablated material does not alter GQDs optical band gap. However, it will slightly reduce both, direct and indirect Oxygen defect related optical band gap.

scholarly journals Green Synthesis and Characterization of Gallium(III) Sulphide (α-Ga2S3) Nanoparicles at Room Temperature

Nano Hybrids ◽  
2014 ◽  
Vol 6 ◽  
pp. 37-46 ◽  
Author(s):  
Tansir Ahamad ◽  
Saad M. Alshehri
Keyword(s):  
Green Synthesis ◽  
Band Gap ◽  
Raman Spectra ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Blue Shift ◽  
Synthesis And Characterization ◽  
Spectroscopic Techniques ◽  
Sodium Thiosulphate

Two different batches of Gallium (III) sulphide nanocrystals, (α-Ga2S3)1 and (α-Ga2S3)2 were synthesized at room temperature by the reaction of Gallium (III) chloride with sodium thiosulphate in water for 10 and 20 min respectively. The resultant nanoparticles were characterized by different spectroscopic techniques. TEM micrographs showed well-defined, close to hexagonal particles, and the lattice fringes in the HRTEM images confirmed their nanocrystalline nature. The sizes of (α-Ga2S3)1 and (α-Ga2S3)2 were 12 and 35 nm respectively with similar morphologies. Optical band gap energies (3.43 eV/3.41 eV) and photoluminescence peaks 635/641 nm (red shift) and 414/420 nm (blue shift) of the synthesized α-Ga2S3 nanocrystals suggest that they may be promising photocatalysts. Raman spectra for the α-Ga2S3, shows very sharp bands at 119, 135 and 148 cm-1 due to Ga-S2 scissoring.

Optical Properties of NiO Thin Films: A Potential Material for Optoelectronic Devices

2012 ◽  
Vol 488-489 ◽  
pp. 103-108 ◽  
Author(s):  
Manisha Tyagi ◽  
Monika Tomar ◽  
Vinay Gupta
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Substrate Temperature ◽  
Band Gap ◽  
Urbach Energy ◽  
Rf Sputtering ◽  
Blue Shift ◽  
Structural Disorder ◽  
Near Ir

The influence of substrate temperature on the UV-Visible-near-IR optical properties, namely the band gap, the Urbach energy and the refractive index of NiO thin films deposited by RF sputtering has been investigated. The optical band gap of thin films showed the blue-shift in the transmission spectra with increase in the substrate temperature which is related to variation in carrier concentration of the deposited films. Urbach energy (EU) values indicate that the films deposited at 400 oC substrate temperature show least structural disorder. The refractive index of the films is found to decrease continuously with increase in the substrate temperature at all photon energies in the visible and near-IR region, and is attributed to the decreasing packing density of the films. Introduction

Semiempirical Correlation between the Optical Band Gap of Oxides and Hydroxides and the Electronegativity of Their Constituents

2000 ◽  
Vol 654 ◽  
Author(s):  
Francesco Di Quarto ◽  
Monica Santamaria ◽  
Salvatore Piazza ◽  
Carmelo Sunseri
Keyword(s):  
Metal Oxides ◽  
Band Gap ◽  
Optical Band Gap ◽  
Experimental Results ◽  
Passive Films ◽  
Metal Hydroxides ◽  
Amorphous Tio2 ◽  
The Difference

AbstractOn the basis of new experimental results a previous proposed correlation between the optical band gap of oxides and the difference of electronegativity of their constituents is extended to mixed crystalline and amorphous TiO2-Fe2O3 (d,d-metal oxides) as well as to amorphous passive films grown on Al-Ta, Al-Ti, Al-Nb and Al-W alloys (sp,d-metal oxides). Moreover in analogy with previous results on anhydrous oxides, a correlation is proposed between the optical band gap of hydroxides and the electronegativities of their constituents after substituting the electronegativity of hydroxilic group to that of the oxygen. Like in the case of anhydrous oxides, two different interpolation lines have been found for sp-metal and d-metal hydroxides, respectively.

Optical Properties of Silica Borotellurite Glass Doped with Manganese Oxide

2017 ◽  
Vol 268 ◽  
pp. 18-22 ◽  
Author(s):  
I. Zaitizila ◽  
Mohamed Kamari Halimah ◽  
Farah Diana Mohammad ◽  
Mohd Shah Nurisya
Keyword(s):  
Optical Properties ◽  
Manganese Oxide ◽  
Band Gap ◽  
Diffraction Pattern ◽  
Optical Band Gap ◽  
Urbach Energy ◽  
Molar Fraction ◽  
Chemical Formula ◽  
Melt Quenching ◽  
Amorphous Nature

Silica borotellurite glasses doped with manganese oxide with chemical formula {[(TeO2)0.7(B2O3)0.3­]0.8[SiO2]0.2}1-x{MnO2}x (where x = 0.0, 0.01, 0.02, 0.03, 0.04 and 0.05 molar fraction) were fabricated. Silica were extracted from the burning process of rice husk. Glass samples were prepared by using the melt-quenching technique. The FTIR spectra showed that the addition of MnO₂ contributed to the transformation of TeO4 to TeO3. The diffraction pattern of XRD showed a broad hump which indicates the amorphous nature of the samples. The result for both optical band gap and Urbach energy showed decreasing trend as the concentration of manganese increased.

Exploring Burstein–Moss type effects in nickel doped hematite dendrite nanostructures for enhanced photo-electrochemical water splitting

2019 ◽  
Vol 21 (36) ◽  
pp. 20463-20477 ◽  
Author(s):  
Soniya Gahlawat ◽  
Jaspreet Singh ◽  
Ashok Kumar Yadav ◽  
Pravin P. Ingole
Keyword(s):  
Optical Properties ◽  
Band Gap ◽  
Water Splitting ◽  
Conduction Band ◽  
Optical Band Gap ◽  
Doped Semiconductors ◽  
Electrochemical Water Splitting

The Burstein–Moss suggests which that the optical band gap of degenerately doped semiconductors increases when all states close to the conduction band get populated is important to obtain different optical properties for the same material.

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