scholarly journals Controlling Molecule Aggregation and Electronic Spatial Coherence in the H-Aggregate and J-Aggregate Regime at Room Temperature

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 786
Author(s):  
Fei Dou ◽  
Jiawei Li ◽  
Huijie Men ◽  
Xinping Zhang
Keyword(s):  
Organic Semiconductors ◽  
Room Temperature ◽  
Solidification Rate ◽  
Spatial Coherence ◽  
Key Factors ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Molecule Aggregation ◽  
The Relationship ◽  
Franck Condon

Controlling molecule aggregation in polymer films is one of the key factors in understanding the links between properties and structures in organic semiconductors. Here, we used poly(3-hexylthiophene-2,5-diyl) (P3HT) as the model system. By doping the insulating polar additive poly (ethylene oxide) (PEO) into P3HT film and controlling the processing methods, we achieved the side-to-side H-aggregate and head-to-tail J-aggregate of P3HT molecules with different extents at room temperature. We have demonstrated that the solvent solidification rate plays an important role in the controlling of molecule aggregation, which finally influenced the solid-state phase separation in the film. Furthermore, based on a series of spectroscopy investigations, we quantified the electronic spatial coherence in different aggregations combined with the modified Franck–Condon model. Subsequently, we established the relationship between the processing method, the molecule aggregation, and the electronic spatial coherence.

scholarly journals Martensitic Transformation and Crystalline Structure of Ni50Mn50−xSnx Melt-Spun Heusler Alloys

Crystals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 853
Author(s):  
Rim Ameur ◽  
Mahmoud Chemingui ◽  
Tarek Bachaga ◽  
Lluisa Escoda ◽  
Mohamed Khitouni ◽  
...  
Keyword(s):  
Martensitic Transformation ◽  
Room Temperature ◽  
Solidification Rate ◽  
Heusler Alloys ◽  
X Ray Diffraction ◽  
Key Factors ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Characteristic Temperatures ◽  
Melt Spun

The structure and thermal behavior are key factors that influence the functional response of Ni–Mn–Sn alloys. The present study reports the production as well as the structure and thermal analysis of melt-spun (solidification rate: 40 ms−1) Ni50 Mn50−xSnx (x = 10, 11, 12 and 13 at.%) alloys. X-ray diffraction measurements were performed at room temperature. The austenite state has an L21 structure, whereas the structure of the martensite is 7M or 10M (depending on the Sn/Mn percentage). Furthermore, the structural martensitic transformation was detected by differential scanning calorimetry (DSC). As expected, upon increasing the Sn content, the characteristic temperatures also increase. The same tendency is detected in the thermodynamic parameters (entropy and enthalpy). The e/a control allows the development production of alloys with a transformation close to room temperature.

A block copolymer of crosslinkable polythiophene and removable poly(ethylene oxide) for preparing heterostructures of organic semiconductors

2017 ◽  
Vol 5 (6) ◽  
pp. 1414-1419 ◽  
Author(s):  
T. Ube ◽  
T. Kosaka ◽  
H. Okazaki ◽  
K. Nakae ◽  
T. Ikeda
Keyword(s):  
Block Copolymer ◽  
Ethylene Oxide ◽  
Organic Semiconductors ◽  
Copolymer Films ◽  
Donor Acceptor ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Block copolymer films composed of polythiophene with cinnamate groups and poly(ethylene oxide) were prepared as template networks of donor/acceptor heterostructures.

Li ion Conduction in Cross-Linked Peo-LiCF3SO3 Complex

1988 ◽  
Vol 135 ◽  
Author(s):  
Jun Tsuchiya
Keyword(s):  
Diffusion Coefficient ◽  
Room Temperature ◽  
Transport Number ◽  
Diffusion Measurement ◽  
Poly Ethylene Oxide ◽  
Li Ion ◽  
Poly Ethylene ◽  
Pfg Nmr ◽  
And Diffusion ◽  
Ion Transport Number

AbstractIonic migration of cross-linked amorphous Poly (Ethylene Oxide)-LiCF3SO3was investigated by measuring ionic conductivity and diffusion coefficient. Pulsed-Field-Gradient NMR (PFG-NMR) was used for the diffusion measurement. The measurements were carried out at a temperature region between room temperature and 120°C. The PFG-NMR mea-surement shows the two modes of migration of both cation(Li) and anion (CF3 SO3-) for specimens containing plasticizer (CH30(CHeiH20)gH3C). The two modes of migration for anion are present for specimens without the plasticizer. Li+ transport number is found to be less than 0.1 for specimens without the plasticizer. Plasticizer is found to increase the Li+ ion transport number.

scholarly journals Structure and Doping Optimization of IDT-Based Copolymers for Thermoelectrics

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1463
Author(s):  
Tongchao Liu ◽  
Dexun Xie ◽  
Jinjia Xu ◽  
Chengjun Pan
Keyword(s):  
Organic Semiconductors ◽  
Carrier Mobility ◽  
Carrier Transport ◽  
Room Temperature ◽  
Charge Carrier Transport ◽  
Structure Property ◽  
Polymer Backbone ◽  
Donor Acceptor ◽  
Higher Carrier Mobility ◽  
The Relationship

π-conjugated backbones play a fundamental role in determining the thermoelectric (TE) properties of organic semiconductors. Understanding the relationship between the structure–property–function can help us screen valuable materials. In this study, we designed and synthesized a series of conjugated copolymers (P1, P2, and P3) based on an indacenodithiophene (IDT) building block. A copolymer (P3) with an alternating donor–acceptor (D-A) structure exhibits a narrower band gap and higher carrier mobility, which may be due to the D-A structure that helps reduce the charge carrier transport obstacles. In the end, its power factor reaches 4.91 μW m−1 K−2 at room temperature after doping, which is superior to those of non-D-A IDT-based copolymers (P1 and P2). These results indicate that moderate adjustment of the polymer backbone is an effective way to improve the TE properties of copolymers.

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