scholarly journals Multi-phase microstructures drive exciton dissociation in neat semicrystalline polymeric semiconductors

2015 ◽  
Vol 3 (41) ◽  
pp. 10715-10722 ◽  
Author(s):  
Francis Paquin ◽  
Jonathan Rivnay ◽  
Alberto Salleo ◽  
Natalie Stingelin ◽  
Carlos Silva-Acuña
Keyword(s):  
Solid State ◽  
Phase Morphology ◽  
Exciton Dissociation ◽  
Multi Phase

The exciton dissociation yield of macromolecular semiconductors depend fundamentally on their solid-state microstructure and phase morphology.

Combustion Synthesis of Sr-Substituted LaCo0.4Fe0.6O3 Powders

1992 ◽  
Vol 271 ◽  
Author(s):  
J. J. Kingsley ◽  
L. A. Chick ◽  
G. W. Coffey ◽  
D. E. McCready ◽  
L. R. Pederson
Keyword(s):  
Solid State ◽  
Metal Oxides ◽  
Mixed Oxides ◽  
Electronic Conductivity ◽  
Solid State Reactions ◽  
Bet Surface Area ◽  
Metal Nitrates ◽  
Subsequent Calcination ◽  
Multi Phase ◽  
Sorption Characteristics

ABSTRACTSr-substituted perovskite LaCo0.4Fe0.6O3 is known to have excellent mixed ionic and electronic conductivity and increased O2 sorption characteristics. These perovskites are usually prepared by lengthy solid-state reactions of the component oxides at temperatures near 1150°C, and often produce inhomogeneous, multi-phase powders. Presently, it has been prepared by the calcination of combustion-derived fine mixed oxides at 850°C in 6 hrs. Combustion reactions are carried out using precursor solutions containing the corresponding metal nitrates (oxidizers) and glycine (fuel) at 250°C. The metal oxides produced by this process and subsequent calcination were characterized by XRD, TEM and BET surface area analysis.

Solid state NMR study of segmented polymer networks: fine-tuning of phase morphology via their molecular design

Polymer ◽  
2004 ◽  
Vol 45 (23) ◽  
pp. 7943-7951 ◽  
Author(s):  
Wouter Lequieu ◽  
Peggy Van De Velde ◽  
Filip E. Du Prez ◽  
Peter Adriaensens ◽  
Liesbet Storme ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Molecular Design ◽  
Polymer Networks ◽  
Phase Morphology ◽  
Fine Tuning ◽  
Nmr Study

Microwave-Assisted Solid State Synthesis of Red-Emitting BCNO Phosphor and its Characteristics

2014 ◽  
Vol 896 ◽  
pp. 464-467 ◽  
Author(s):  
Bebeh Wahid Nuryadin ◽  
Ea Cahya Septia ◽  
Ferry Iskandar ◽  
Takashi Ogi ◽  
Kikuo Okuyama ◽  
...  
Keyword(s):  
Solid State ◽  
Uv Light ◽  
Hexagonal Boron Nitride ◽  
Low Cost ◽  
Broad Emission Band ◽  
Photoluminescence Properties ◽  
Carbon And Nitrogen ◽  
Microwave Assisted ◽  
Carbon And Nitrogen Content ◽  
Multi Phase

Red-emitting BCNO phosphor has been synthesized by a microwave-assisted solid state reaction using a low-cost boric acid, urea and polyethylene glycol (PEG-20k) as the starting materials. The effects of reaction parameters: temperature, carbon and nitrogen content on material composition and photoluminescence properties were investigated. Nearly multi-phase hexagonal boron nitride, boron oxide, boron carbide and carbon graphite was observed, indicating the BCNO were successfully synthesized. The photoluminescence spectra of the phosphor excited by a UV light (365 nm) showed a broad emission band at 460 - 620 nm.

Modeling of Multi-Phase Solid State Reactions-Case of IMC Growth

2012 ◽  
Vol 323-325 ◽  
pp. 127-132
Author(s):  
M. Pawełkiewicz ◽  
Marek Danielewski ◽  
Jolanta Janczak-Rusch ◽  
Bartek Wierzba
Keyword(s):  
Solid State ◽  
Joint Strength ◽  
Void Formation ◽  
Solid State Reactions ◽  
Reactive Diffusion ◽  
Metallurgical Bond ◽  
Multi Phase ◽  
Reaction Processes ◽  
Different Time Scales ◽  
Simultaneous Growth

The formation of intermetallic compounds (IMC) at the solder-substrate interface is required to initiate the metallurgical bond. However, rapid growth of IMCs may degrade joint strength through i) the increased presence of a low toughness phase, ii) the consumption of the solderable surface (void formation) and iii) generation of primary and secondary stresses. Knowledge of mass transport and reaction processes during joint formation and service life are essential for solder system design. The mathematical description of inter-and reactive diffusion in open system presented here is based on Darken method (bi-velocity), involving the different molar volumes in the system and Wagner boundary conditions. It combines the interdiffusion, reactive diffusion and the effective flux constraints to couple processes occurring at different time scales. The rCADiff software serves as a tool to simulate simultaneous growth of the two Cu-Sn IMCs.

X-Ray Analysis of New Gadolinium Doped CuCr2Se4

2013 ◽  
Vol 203-204 ◽  
pp. 146-149
Author(s):  
Ewa Maciążek ◽  
Paweł Zajdel ◽  
Izabela Jendrzejewska ◽  
Maja Mendakiewicz
Keyword(s):  
Solid State ◽  
Spinel Phase ◽  
Structure Refinement ◽  
Solid State Reaction Method ◽  
Solubility Limit ◽  
Detailed Structure ◽  
Reaction Method ◽  
X Ray ◽  
Multi Phase ◽  
Low Solubility

Abstract. Phase and structure analysis of CuCr2-xGdxSe4 (x=0.1÷0.3) synthesized using a solid state reaction method were carried out using X-Ray powder diffraction. All obtained compounds were found to be multi phase with the spinel phase being dominant up to x=0.1, indicating low solubility limit of gadolinium. Two compounds CuCr1.95Gd0.05Se4 and CuCr1.9Gd0.1Se4,. were chosen for a detailed structure refinement.

scholarly journals Slow recombination of spontaneously dissociated organic fluorophore excitons

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Takahiko Yamanaka ◽  
Hajime Nakanotani ◽  
Chihaya Adachi
Keyword(s):  
Solid State ◽  
Quantum Yield ◽  
Organic Molecules ◽  
Light Emission ◽  
Binding Energies ◽  
Electrical Excitation ◽  
Exciton Dissociation ◽  
Light Emitting ◽  
Solid Films ◽  
Organic Fluorophore

AbstractThe harvesting of excitons as luminescence by organic fluorophores forms the basis of light-emitting applications. Although high photoluminescence quantum yield is essential for efficient light emission, concentration-dependent quenching of the emissive exciton is generally observed. Here we demonstrate generation and accumulation of concentration-dependent “long-lived” (i.e., over 1 h) photo-generated carriers and the successive release of their energy as electroluminescence in a solid-state film containing a polar fluorophore. While fluorophore excitons are generally believed to be stable because of their high exciton binding energies, our observations show that some of the excitons undergo spontaneous exciton dissociation in a solid-state film by spontaneous orientation polarization even without an external electric field. These results lead to the reconsideration of the meaning of “luminescence quantum yield” for the solid films containing polar organic molecules because it can differ for optical and electrical excitation.

Study of the Influence of the V in the Zr2Fe Alloy from Hydrogen Storage on Thermodynamic Properties

2019 ◽  
Vol 31 ◽  
pp. 22-29 ◽  
Author(s):  
Alejandro Martinez ◽  
Darío Peña ◽  
Daniela Bellon
Keyword(s):  
Solid State ◽  
Hydrogen Storage ◽  
Room Temperature ◽  
The United States ◽  
Department Of Energy ◽  
Synthesis Process ◽  
United States Department ◽  
Stoichiometric Ratio ◽  
Desorption Kinetic ◽  
Multi Phase

Hydrogen storage in its solid state is one of the main challenges for mobile and stationary applications. Some metal hydrides are potential candidates for energy storage. This is an experimental research, which represents a contribution to the study of Hydrogen storage in its solid state, by studying the influence of the proportional substitution of V for Zr in the stoichiometric ratio Zr2-XVXFe (X=0.0, 0.1 y 0.2). Results indicate that the synthesis process generates a multi-phase type microstructure, and the absorption and desorption kinetic is less than 5 minutes at room temperature, in line with the parameters established by the United States Department of Energy; however, it is clear that the desorption capacity decreases.

scholarly journals Multi-phase powder patterns in characterization of new solid-state materials

2017 ◽  
Vol 73 (a2) ◽  
pp. C948-C948
Author(s):  
Vladimir V. Chernyshev ◽  
Vera I. Isaeva ◽  
Anna A. Lobova
Keyword(s):  
Solid State ◽  
Solid State Materials ◽  
Multi Phase
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