Enhancement of Exciton Emission in Lead Halide-Based Layered Perovskites by Cation Mixing

2016 ◽  
Vol 16 (4) ◽  
pp. 3338-3342 ◽  
Author(s):  
Masanao Era ◽  
Yumeko Komatsu ◽  
Naotaka Sakamoto
Keyword(s):  
Solid Solution ◽  
Room Temperature ◽  
Divalent Cations ◽  
Divalent Metal ◽  
Metal Halide ◽  
Layered Perovskite ◽  
Organic Layer ◽  
Exciton Emission ◽  
Lead Halide ◽  
Layered Perovskites

Spin-coated films of a lead halide, PbX: X = I and Br, layered perovskites having cyclohexenylethyl ammonium molecule as an organic layer, which were mixed with other metal halide-based layered perovskites consisting of various divalent metal halides (for example, CaI2, CdI2, FeI2, SnBr2 and so on), were prepared. The results of X-ray diffraction measurements exhibited that solid solution formation between PbX-based layered perovskite and other divalent metal halide-based layered perovskites was observed up to very high molar concentration of 50 molar% in the mixed film samples when divalent cations having ionic radius close to that of Pb2+ were employed. In the solid solution films, the exciton emission was much enhanced at room temperature. Exciton emission intensity of PbI-based layered perovskite mixed with CaI-based layered perovskite (20 molar%) is about 5 times large that of the pristine PbI-based layered perovskite, and that of PbBr-based layered perovskite mixed with SnBr-based layered perovskite (20 molar%) was also about 5 times large that of the pristine PbBr-based layered perovskite at room temperature.

PbBr-Based Layered Perovskite Organic–Inorganic Superlattice Having Carbazole Chromophore; Hole-Mobility and Quantum Mechanical Calculation

2016 ◽  
Vol 16 (4) ◽  
pp. 3159-3167 ◽  
Author(s):  
Masanao Era ◽  
Takeshi Yasuda ◽  
Kento Mori ◽  
Norio Tomotsu ◽  
Naoki Kawano ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Substrate Temperature ◽  
Threshold Voltage ◽  
Room Temperature ◽  
Hole Mobility ◽  
Layered Perovskite ◽  
Quantum Mechanical ◽  
Organic Layer ◽  
Si Substrates ◽  
The Mean

We have successfully evaluated hole mobility in a spin-coated film of a lead-bromide based layered perovskite having carbazole chromophore-linked ammonium molecules as organic layer by using FET measurement. The values of hole mobility, threshold voltage and on/off ratio at room temperature were evaluated to be 1.7×10−6 cm2 V−1 s−1, 27 V and 28 V, respectively. However, the spin-coated films on Si substrates were not so uniform compared with those on fused quartz substrates. To improve the film uniformity, we examined the relationship between substrate temperature during spin-coating and film morphology in the layered perovskite spin-coated films. The mean roughness of the spin-coated films on Si substrates was dependent on the substrate temperature. At 353 K, the mean roughness was minimized and the carrier mobility was enhanced by one order of magnitude; the values of hole mobility and threshold voltage were estimated to be 3.4×10−5 cm2 V−1 s−1, and 22 V at room temperature in a preliminary FET evaluation, respectively. In addition, we determined a crystal structure of the layered perovskite by X-ray diffraction analysis. To gain a better understanding of the observed hole transports, we conducted quantum mechanical calculations using the obtained crystal structure information. The calculated band structure of the layered organic perovskite showed that the valence band is composed of the organic carbazole layer, which confirms that the measured hole mobility is mainly derived from the organic part of the layered perovskite. Band and hopping transport mechanisms were discussed by calculating the effective masses and transfer integrals for the 2D periodic system of the organic layer in isolation.

Effects of Mg2+ on Chromatic Structure in Isolated Chicken Liver Nuclei

1990 ◽  
Vol 48 (3) ◽  
pp. 130-131
Author(s):  
Soichiro Arai ◽  
Yuh H. Nakanishi
Keyword(s):  
Chromatin Structure ◽  
Room Temperature ◽  
Osmium Tetroxide ◽  
Divalent Cations ◽  
Chromatin Condensation ◽  
Chicken Liver ◽  
Electron Microscopic ◽  
Razor Blade ◽  
Microscopic Studies ◽  
Liver Nuclei

Although many electron microscopic studies on extracted chromatin have provided considerable information on chromatin condensation induced by divalent cations, there is only a little literature available on the effects of divalent cations on chromatin structure in intact nuclei. In the present study, the effects of Mg2+ on chromatin structure in isolated chicken liver nuclei were examined over a wide concentration range of Mg2+ by scanning electron microscopy.Nuclei were prepared from chicken liver by the method of Chauveau et al. with some modifications. The nuclei were suspended in 25 mM triethanolamine chloride buffer (pH7.4) with 1 mM EDTA or in the buffer with concentrations of MgCl2 varying from 1 to 50 mM. After incubation for 1 min at 0°C, glutaraldehyde was added to 1.8% and the nuclei were fixed for 1 h at 4°C. The fixed nuclei were mixed with 15% gelatin solution warmed at about 40°C, and kept at room temperature until the mixture set. The gelatin containing the nuclei was fixed with 2% glutaraldehyde for 2-4 h, and cut into small blocks. The gelatin blocks were conductive-stained with 2% tannic acid and 2% osmium tetroxide, dehydrated in a graded series of ethanol, and freeze-cracked with a razor blade in liquid nitrogen.

scholarly journals Preparation of Li3PS4–Li3PO4 Solid Electrolytes by Liquid-Phase Shaking for All-Solid-State Batteries

2021 ◽  
Vol 2 (1) ◽  
pp. 39-48
Author(s):  
Nguyen H. H. Phuc ◽  
Takaki Maeda ◽  
Tokoharu Yamamoto ◽  
Hiroyuki Muto ◽  
Atsunori Matsuda
Keyword(s):  
Solid Solution ◽  
Solid State ◽  
Liquid Phase ◽  
Room Temperature ◽  
Reaction Medium ◽  
Magic Angle Spinning ◽  
Resonance Spectroscopy ◽  
Synthesis Methods ◽  
Magic Angle ◽  
Angle Spinning

A solid solution of a 100Li3PS4·xLi3PO4 solid electrolyte was easily prepared by liquid-phase synthesis. Instead of the conventional solid-state synthesis methods, ethyl propionate was used as the reaction medium. The initial stage of the reaction among Li2S, P2S5 and Li3PO4 was proved by ultraviolet-visible spectroscopy. The powder X-ray diffraction (XRD) results showed that the solid solution was formed up to x = 6. At x = 20, XRD peaks of Li3PO4 were detected in the prepared sample after heat treatment at 170 °C. However, the samples obtained at room temperature showed no evidence of Li3PO4 remaining for x = 20. Solid phosphorus-31 magic angle spinning nuclear magnetic resonance spectroscopy results proved the formation of a POS33− unit in the sample with x = 6. Improvements of ionic conductivity at room temperature and activation energy were obtained with the formation of the solid solution. The sample with x = 6 exhibited a better stability against Li metal than that with x = 0. The all-solid-state half-cell employing the sample with x = 6 at the positive electrode exhibited a better charge–discharge capacity than that employing the sample with x = 0.

scholarly journals Mechanism of Additive-Assisted Room-Temperature Processing of Metal Halide Perovskite Thin Films

2021 ◽  
Author(s):  
Maged Abdelsamie ◽  
Tianyang Li ◽  
Finn Babbe ◽  
Junwei Xu ◽  
Qiwei Han ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Metal Halide ◽  
Metal Halide Perovskite ◽  
Halide Perovskite

Microstructure and wear resistance of Cuss-toughened Cr5Si3/CrSi metal silicide alloys

2005 ◽  
Vol 20 (5) ◽  
pp. 1122-1130 ◽  
Author(s):  
Y.X. Yin ◽  
H.M. Wang
Keyword(s):  
Solid Solution ◽  
Wear Resistance ◽  
Sliding Wear ◽  
Room Temperature ◽  
Wear Test ◽  
Melting Process ◽  
Dry Sliding Wear ◽  
Metal Silicide ◽  
X Ray Diffraction ◽  
X Ray

Wear-resistant Cu-based solid-solution-toughened Cr5Si3/CrSi metal silicide alloy with a microstructure consisting of predominantly the dual-phase primary dendrites with a Cr5Si3 core encapsulated by CrSi phase and a small amount of interdendritic Cu-based solid solution (Cuss) was designed and fabricated by the laser melting process using Cr–Si–Cu elemental powder blends as the precursor materials. The microstructure of the Cuss-toughened Cr5Si3/CrSi metal silicide alloy was characterized by optical microscopy, powder x-ray diffraction, and energy dispersive spectroscopy. The Cuss-toughened silicide alloys have excellent wear resistance and low coefficient of friction under room temperature dry sliding wear test conditions with hardened 0.45% C carbon steel as the sliding–mating counterpart.

An Above-Room-Temperature Ferroelectric Organo-Metal Halide Perovskite: (3-Pyrrolinium)(CdCl3)

2014 ◽  
Vol 53 (42) ◽  
pp. 11242-11247 ◽  
Author(s):  
Heng-Yun Ye ◽  
Yi Zhang ◽  
Da-Wei Fu ◽  
Ren-Gen Xiong
Keyword(s):  
Room Temperature ◽  
Metal Halide ◽  
Metal Halide Perovskite ◽  
Halide Perovskite

Reducing the leakage current for a CsPbBr3 detector via asymmetric area electrodes and heterostructures

2021 ◽  
Author(s):  
YingFeng Ruan ◽  
Pengju Guo ◽  
Zhiping Zheng ◽  
Qiuyun Fu ◽  
Rongda Zhou ◽  
...  
Keyword(s):  
Leakage Current ◽  
Room Temperature ◽  
Next Generation ◽  
Typical Representative ◽  
X Ray ◽  
Inorganic Lead ◽  
Halide Perovskites ◽  
Lead Halide

As a typical representative of all-inorganic lead halide perovskites, cesium lead bromine (CsPbBr3) has been regarded as the workhorse of next-generation room temperature X-ray detectors in recent years.

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