Scherrer formula and Williamson-Hall plot or WH-plot are the common methods to determine microstructure information from diffraction pattern, a technique with the expenses of the physical meaning of ...the result. Eventually a Whole Powder Pattern Modeling (WPPM) has been proposed, allowing physical information to be extracted from the diffraction data with the one-step refinement of the experimental pattern. In this paper, we reported the comparison between Williamson-Hall plot and Whole Powder Pattern Modeling to determine the crystallite size of nanoparticle barium hexaferrites which prepared by mechanical alloying and direct ultrasonic destruction.
Partially Zn-substituted for Cu in electron-doped superconducting cuprates of Eu1.85Ce0.15Cu1-yZny4+α-δ (ECCZO) with y = 0, 0.01, 0.02, 0.05 and various δ values have been studied in order to ...elucidate the effect of nonmagnetic impurity of Zn to their structure and resistivity properties in the electron-doped cuprates. It has been found that the main peaks of T' structures are clearly observed in all samples. Superconductivity disappeared with Zn substitution for Cu in electron-doped system of ECCZO.
•We reported temperature dependence of ρ and χ of partially Zn-substituted electron-doped superconducting cuprates of ECCZO.•It has been found that onset of critical temperature (Tc) was observed at ...about 13 K in with y = 0 for δ values of 0.095.•With increasing Zn concentration, onset of Tc disappeared indicating the destruction of superconductivity properties by Zn.•Partially Zn subsitution for Cu in ECCO can decreased radius of localization of electron in normal state at low temperatures.•This result may related to the stripe pinning by Zn as observed in hole-doped cuprates.
Transport and magnetic properties of electron-doped superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4+α-δ (ECCZO) with y = 0, 0.01, 0.02 and 0.05 have been studied from electrical resistivity and magnetic susceptibility measurements, in order to elucidate the effect of partially Zn-substitution for Cu to its superconductivity and localization of electron in normal state. It has been found that the onset of the critical temperature (Tc) from electrical resistivity and magnetic susceptibility measurements was observed at 13 K for y = 0 and δ values of 0.095. With increasing Zn concentration, the onset of Tc disappeared, indicating the destruction of superconductivity properties by Zn. Moreover, 0.01 of Zn substitution for Cu decreased radius of localization of electron (r) in normal state at low temperatures that may related to the evident of stripe-pinning effects by Zn in electron-doped system of ECCZO. Analysis of magnetic susceptibility data in normal state found a Zn-induced local moments in electron-doped high-Tc superconducting cuprates of ECCZO as observed in hole-doped cuprates.
The effect of Zn substitution to the Cu-spin fluctuation in Eu1.85Ce0.15Cu1-yZnyO4+α-δ with y = 0, 0.01, 0.02, and 0.05 has been studied from zero-field (ZF) muon-spin-relaxation (μSR) measurements ...to understand Zn-induced magnetic state in electron-doped high-Tc superconducting cuprates. It was found that the Cu-spin correlation was developed through Zn substitution. These results were similar to the results of ZF-□SR measurements in the holedoped cuprates La2-xSrxCu1-yZnyO4, leading to the view electron-hole doping symmetry in high-Tc superconductors.
Perovskite methylammonium lead tri-bromide (MAPbBr3) material has gained a lot of attention in the past few years due to its impressive optoelectronic properties, which is suitable for high ...efficiency and sensitivity X-ray photodetector. Compared to polycrystalline crystal structure, MAPbBr3 single crystal is more ideal for X-ray photodetector because lack of grain boundary therefore produce more sensitive photodetector. However, a cubic structure and large crystal dimension is highly required to adjust into the flat-panel detector configuration. In this research, MAPbBr3 perovskite crystals were synthesized by using Anti-solvent Vapor-assisted Crystallization (AVC) at room temperature using dimethylformamide (DMF) as solvent and Dichloromethane (DCM) as antisolvent. The precursors for the MAPbBr3 solution were prepared by varying the molar ratio of MABr:PbBr2 as precursor solution. The crystal growth rate was controlled by varying the volume ratio of DCM and MAPbBr3 precursor solution. The obtained largest crystal size of 10 mm × 10 mm was prepared with a volume ratio of DCM and precursor is 3 and a volume of precursor solution is 6 ml. The XRD of large cubic MAPbBr3 crystal showed a peak of (100) plane, which indicates a single crystal oriented in a-axis direction. The Raman spectra peaks of perovskite MAPbBr3 crystals showed organic (MA+) and inorganic (PbBr2−) bonds in a cubic phase of single crystal MAPbBr3. All samples that were prepared with different ratios of DCM and precursor solution have the same Raman spectra, which confirm that all MAPbBr3 crystals have cubic crystal structure.
Abstract
Perovskite methylammonium lead tri-bromide (MAPbBr
3
) material has gained a lot of attention in the past few years due to its impressive optoelectronic properties, which is suitable for ...high efficiency and sensitivity X-ray photodetector. Compared to polycrystalline crystal structure, MAPbBr
3
single crystal is more ideal for X-ray photodetector because lack of grain boundary therefore produce more sensitive photodetector. However, a cubic structure and large crystal dimension is highly required to adjust into the flat-panel detector configuration. In this research, MAPbBr
3
perovskite crystals were synthesized by using Anti-solvent Vapor-assisted Crystallization (AVC) at room temperature using dimethylformamide (DMF) as solvent and Dichloromethane (DCM) as antisolvent. The precursors for the MAPbBr
3
solution were prepared by varying the molar ratio of MABr:PbBr
2
as precursor solution. The crystal growth rate was controlled by varying the volume ratio of DCM and MAPbBr
3
precursor solution. The obtained largest crystal size of 10 mm × 10 mm was prepared with a volume ratio of DCM and precursor is 3 and a volume of precursor solution is 6 ml. The XRD of large cubic MAPbBr
3
crystal showed a peak of (100) plane, which indicates a single crystal oriented in
a-axis
direction. The Raman spectra peaks of perovskite MAPbBr
3
crystals showed organic (MA
+
) and inorganic (PbBr
2
−
) bonds in a cubic phase of single crystal MAPbBr
3
. All samples that were prepared with different ratios of DCM and precursor solution have the same Raman spectra, which confirm that all MAPbBr
3
crystals have cubic crystal structure.
This investigation explored the structural, magnetic, and magnetic entropy change characteristics of La0.7Ba0.25Nd0.05Mn1-xZnxO3 (x = 0.03 and 0.05) synthesized through the sol-gel method. The ...structural analysis revealed the crystallization of both samples in a Rhombohedral structure with the R-3c space group. The examination of magnetic properties indicated a suppression in magnetic behavior, with the ferromagnetic-paramagnetic transition temperature (TC) decreasing from 285 K to approximately 260 K with an increase in Zn content (x) from 0.03 to 0.05, respectively. The maximum value of magnetic entropy change (−ΔSM) under an applied magnetic field of 50 kOe was determined to be 3.96 J/kg·K for x = 0.03 and 2.27 J/kg·K for x = 0.05. Analysis of Arrot plots and the universal curve of magnetic entropy change confirmed that the ferromagnetic-paramagnetic phase transition observed in both samples exhibits a second-order phase transition (SOPT) transformation.
Electron-doped superconducting cuprates of Eu2-xCexCu1-yNiyO4+a-d in under-doped region with x = 0.12 and y = 0, 0.01, 0.02, 0.03 and 0.05 have been prepared, characterized and investigated in order ...to study the effect of Ni impurity to the magnetic properties of electron doped superconducting cuprates. All main peaks of tetragonal and T’ structure configuration of ECCO were observed in all samples. Temperature dependence of dc magnetic-susceptibility on field cooling at 5 Oe for Eu1.88Ce0.12Cu1-yNiyO4+a-d with d values from 0.0496 to 0.08322 shows diamagnetic behavior for sample with y = 0, starting from about 11 K. For sample with y = 0.01, Tc onset decreases to be around 4 K. The superconductivity disappeared at y ≥ 0.02 indicating 2 % Ni substitution to the Cu has weakened the spin-spin correlation and reduced the value of magnetization in ECCO system.
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