Influence of activation energy on charge conduction mechanism and giant dielectric relaxation of sol-gel derived C3H7NH3PbBr3 perovskite; Act as high performing UV photodetector

2022 ◽  
Vol 892 ◽  
pp. 162216
Author(s):  
Payal Sengupta ◽  
Priyabrata Sadhukhan ◽  
Apurba Ray ◽  
Souvik Mal ◽  
Anar Singh ◽  
...  
2018 ◽  
Vol 36 (1) ◽  
pp. 112-122 ◽  
Author(s):  
Tanusree Mondal ◽  
Sayantani Das ◽  
T.P. Sinha ◽  
P.M. Sarun

AbstractThis work aims to study the electrical conduction mechanism in the dielectric material BaZr0.1Ti0.9O3(BZT) ceramics by applying AC signal in the frequency range of 102Hz to 106Hz. The phase purity and microstructure of the sample have been studied by X-ray diffraction refinement and field-emission scanning electron microscope (FE-SEM) analysis. The appearance of resonance peaks in the loss tangent at high temperature is due to inherent dielectric relaxation processes of this oxide. The temperature dependent Cole-Cole plot has been studied in details to determine both the grain and grain boundary contribution to the conductivity. Electrical modulus analysis reveals that the hopping of charge carriers is the most probable conduction mechanism in BZT ceramics. The obtained data of AC conductivity obey the universal double power law and have been discussed in terms of microstructural network characteristics. The behavior of frequency exponent n of AC conductivity as a function of temperature verify the applicability of the correlated barrier hopping (CBH) model. The AC conductivity data are used to estimate the minimum hopping length, density of states at Fermi level, thermal conductivity and apparent activation energy. The value of activation energy confirms that the oxygen vacancies play a vital role in the conduction mechanism.


2015 ◽  
Vol 8 (3) ◽  
pp. 2176-2188 ◽  
Author(s):  
Keisham Nanao Singh

This article reports on the Dielectric Relaxation Studies of two Liquid Crystalline compounds - 7O.4 and 7O.6 - doped with dodecanethiol capped Silver Nanoparticles. The liquid crystal molecules are aligned homeotropically using CTAB. The low frequency relaxation process occurring above 1 MHz is fitted to Cole-Cole formula using the software Dielectric Spectra fit. The effect of the Silver Nanoparticles on the molecular dipole dynamics are discussed in terms of the fitted relaxation times, Cole-Cole distribution parameter and activation energy. The study indicate a local molecular rearrangement of the liquid crystal molecules without affecting the order of the bulk liquid crystal molecules but these local molecules surrounding the Silver Nanoparticles do not contribute to the relaxation process in the studied frequency range. The observed effect on activation energy suggests a change in interaction between the nanoparticles/liquid crystal molecules.


2002 ◽  
Vol 16 (17n18) ◽  
pp. 2454-2460 ◽  
Author(s):  
X. P. ZHAO ◽  
X. DUAN

In-situ sol-gel method to prepare colloidal hybrids of surfactant modified polysucchride and titanium oxide has been presented, and experiments indicated these highly ER active particles exhibited a remarkable ER effect. The static shear stress can be up to 37 k Pa (shear rate 5 S -1) under DC field of 4 kV/mm at root temperature, well above that of simple blends of starch and TiO 2. In the meanwhile, temperature dependence and sedimentation stability were also greatly improved. Based on recent experimental facts, we find that dielectric properties and surface (interface) activity are two necessary conditions fulfilling the requirement of high ER activity. Adequate grinding of particles with oil can effectively enhance the shear stress, which may be owed to the decline of the activation energy needed for restructuring. It has provided us a new horizon for preparation of excellent ER materials and further studies should be continued to make.


RSC Advances ◽  
2021 ◽  
Vol 11 (35) ◽  
pp. 21767-21780
Author(s):  
Mohamed Ben Bechir ◽  
Mohamed Houcine Dhaou

The conduction mechanism in CsSnCl3 is interpreted through the following two approaches: the non-overlapping small polaron tunneling (NSPT) model (monoclinic phase) and the overlapping large polaron tunneling (OLPT) model (cubic phase).


2016 ◽  
Vol 34 (1) ◽  
pp. 164-168
Author(s):  
Raz Muhammad ◽  
Muhammad Uzair ◽  
M. Javid Iqbal ◽  
M. Jawad Khan ◽  
Yaseen Iqbal ◽  
...  

AbstractCa2Nd4Ti6O20, a layered perov skite structured material was synthesized via a chemical (citrate sol-gel) route for the first time using nitrates and alkoxide precursors. Phase analysis of a sample sintered at 1625 °C revealed the formation of an orthorhombic (Pbn21) symmetry. The microstructure of the sample after sintering comprised rod-shaped grains of a size of 1.5 to 6.5µm. The room temperature dielectric constant of the sintered sample was 38 at 100 kHz. The remnant polarization (Pr) and the coercive field (Ec) were about 400 μC/cm2 and 8.4 kV/cm, respectively. Impedance spectroscopy revealed that the capacitance (13.7 pF) and activation energy (1.39 eV) of the grain boundary was greater than the capacitance (5.7 pF) and activation energy (1.13 eV) of the grain.


2011 ◽  
Vol 53 (8) ◽  
pp. 1564-1568 ◽  
Author(s):  
R. M. Sardarly ◽  
O. A. Samedov ◽  
A. P. Abdullaev ◽  
F. T. Salmanov

2019 ◽  
Vol 36 (1) ◽  
pp. 8-13 ◽  
Author(s):  
Chee Yong Fong ◽  
Sha Shiong Ng ◽  
NurFahana Mohd Amin ◽  
Fong Kwong Yam ◽  
Zainuriah Hassan

Purpose This study aims to explore the applicability of the sol-gel-derived GaN thin films for UV photodetection. Design/methodology/approach GaN-based ultraviolet (UV) photodetector with Pt Schottky contacts was fabricated and its applicability was investigated. The current-voltage (I-V) characteristics of the GaN-based UV photodetector under the dark current and photocurrent were measured. Findings The ideality factors of GaN-based UV photodetector under dark current and photocurrent were 6.93 and 5.62, respectively. While the Schottky barrier heights (SBH) for GaN-based UV photodetector under dark current and photocurrent were 0.35 eV and 0.34 eV, respectively. The contrast ratio and responsivity of this UV photodetector measured at 5 V were found to be 1.36 and 1.68 μA/W, respectively. The photoresponse as a function of time was measured by switching the UV light on and off continuously at different forward biases of 1, 3 and 6 V. The results showed that the fabricated UV photodetector has reasonable stability and repeatability. Originality/value This work demonstrated that GaN-based UV photodetector can be fabricated by using the GaN thin film grown by low-cost and simple sol-gel spin coating method.


2002 ◽  
Vol 44 (11) ◽  
pp. 2039-2049 ◽  
Author(s):  
V. V. Lemanov ◽  
A. V. Sotnikov ◽  
E. P. Smirnova ◽  
M. Weihnacht

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