Tuning the bandgap of ZnO by substitution with Mn2+, Co2+ and Ni2+

Bhat, S. Venkataprasad; Deepak, Francis Leonard

doi:10.1016/j.ssc.2005.05.051

Cited by 209 publications

(63 citation statements)

References 11 publications

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“…It has been observed earlier by other groups [13,14] that upon Mn doping in ZnO the band gap reduces for low concentration doping (< 3 mol% of Mn) and for higher concentration ( > 3 mol%) the band gap increases as expected on the basis of virtual crystal approximation (VCA) because of the band gap of the MnO ~ 4.2 eV. In many dilute magnetic semiconductor (DMS) systems such deviation from the linear monotonic increase in the form of "band gap bowing" has been observed [15][16][17][18][19][20][21] …”

Section: Introductionsupporting

confidence: 76%

Influence of Mn doping on the microstructure and optical property of ZnO

Senthilkumaar

Rajendran²,

Banerjee

et al. 2008

Materials Science in Semiconductor Processing

285

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Undoped and Mn doped ZnO samples with different percentage of Mn content (1 mol%, 2 mol% and 3mol%) were synthesized by a simple solvo-thermal method. We have studied the structural, chemical and optical properties of the samples by using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray (EDX) analysis, Fourier transform infrared (FTIR) spectroscopy and UV-VIS spectroscopy. The XRD spectra show that all the samples are hexagonal wurtzite structures. The lattice parameters calculated for the Mn doped ZnO from the XRD pattern were found to be slightly larger than those of the undoped ZnO, which indicates substitution of Mn in ZnO lattice. SEM photograph shows the grain size of undoped ZnO is bigger than the Mn doped ZnO's indicating hindrance of grain growth upon Mn doping. As the Mn doping increases the optical band gap decreases for the range of Mn doping reported here.

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Section: Introductionsupporting

confidence: 76%

Influence of Mn doping on the microstructure and optical property of ZnO

Senthilkumaar

Rajendran²,

Banerjee

et al. 2008

Materials Science in Semiconductor Processing

285

View full text Add to dashboard Cite

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“…Co(II). A similar observation was made for Co(II) doped ZnO, 44,45 an increase is observed for cations such as Al(III) and Ga(III), with a larger mass difference than Zn(II) and Co(II). 46 Considering the literature data for the values of the band gap i.e.…”

Section: Specific Surface Area (Ssa) Pore Volume and Average Pore DIsupporting

confidence: 78%

Mixed Metal Oxides of the Type CoxZn1–xFe2O4 as Photocatalysts for Malachite Green Degradation Under UV Light Irradiation

Tzvetkov¹,

Milanova²,

Cherkezova‐Zheleva

et al. 2017

ACSi

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A combination of thermal and mechanical (high energy ball milling) treatment was applied in an attempt to obtain polycrystalline mixed metal binary and ternary oxides of the type Co x Zn 1-x Fe 2 O 4 (x = 0; 0.25; 0.5; 0.75; 1). The synthetic procedure used successfully produced single-phased, homogeneous ZnFe 2 O 4 , CoFe 2 O 4 , and Co 0.75 Zn 0.25 Fe 2 O 4 , as well as mixed oxides, whose composition depended both on the duration of the high energy ball milling and the ratio Zn(II)/Co(II). The formation of spinel-like structures was proved by XRD, Mössbauer spectroscopy and Raman spectroscopy. For the characterization of the samples low-temperature N 2 adsorption, UV/Vis spectroscopy and transmission electron microscopy were applied. The energy band gap of the samples was calculated, suggesting they are promising photocatalysts. The decomposition of the Malachite Green in model water solutions under UV-light irradiation was successfully achieved in the presence of the samples as photocatalysts. The highest rate constant was obtained for the sample synthesized at longer milling time in combination with higher Zn(II)/Co(II) ratio. The photocatalytic activity of the ternary mixed oxides was compared with the pure hematite, α-Fe 2 O 3 , and the binary ZnFe 2 O 4 and CoFe 2 O 4 ferrites with spinel structure that were treated in the same way. A synergetic effect of α-Fe 2 O 3 and the spinel-like structure on the photocatalytic properties of ternary mixed metal oxides was detected.

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“…5(d)] shows a rapid increase from 3.23 6 0.01 to 3.27 6 0.01 eV when increasing the RF-power from 30 to 40 W and then increases further to 3.28 6 0.02 eV for 150 W. This allows for bandgap tuning in a small range without the need for dopants, 54,55 applicable in a range of optical and electronic applications. The obtained value for the bandgap using Tauc fitting compares well with the literature; for example, Viezbicke et al 41 found an average value for the bandgap of 3.276 6 0.033 eV, comparing a large number of publications on thin film ZnO.…”

Section: B Tuning Of Structural and Optical Properties By Rf-powermentioning

confidence: 97%

Tuning of material properties of ZnO thin films grown by plasma-enhanced atomic layer deposition at room temperature

Pilz¹,

Perrotta

Christian

et al. 2017

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

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The ability to grow inorganic thin films with highly controllable structural and optical properties at low substrate temperature enables the manufacturing of functional devices on thermo-sensitive substrates without the need of material postprocessing. In this study, the authors report on the growth of zinc oxide films by direct plasma-enhanced atomic layer deposition at near room temperature. Diethyl zinc and oxygen plasma were used as the precursor and coreactant, respectively. The process was optimized with respect to the precursor and coreactant dosing as well as to the purging times, which ultimately resulted in saturated atomic layer deposition growth. The so-obtained films exhibit a polycrystalline pattern with a (100) texture and low amount of incorporated carbon. Furthermore, the possibility to tune crystallite size, refractive index, and bandgap of the films by adapting the plasma radio-frequency power is demonstrated.

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Tuning the bandgap of ZnO by substitution with Mn2+, Co2+ and Ni2+

Cited by 209 publications

References 11 publications

Influence of Mn doping on the microstructure and optical property of ZnO

Influence of Mn doping on the microstructure and optical property of ZnO

Mixed Metal Oxides of the Type CoxZn1–xFe2O4 as Photocatalysts for Malachite Green Degradation Under UV Light Irradiation

Tuning of material properties of ZnO thin films grown by plasma-enhanced atomic layer deposition at room temperature

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