Related Experiment Video
Updated: May 15, 2025
08:59
Concurrent Quantitative Conductivity and Mechanical Properties Measurements of Organic Photovoltaic Materials using AFM
Published on: January 23, 2013
11.6K
Regioregular Alternating Polychalcogenophenes-Block-Poly(3-hexylthiophene): Synthesis, Structural Characterizations,
Yung-Jing Xue1, Huai-Hsuan Liu1, Kuo-Hsiu Huang1
1Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu, 30010, Taiwan.
Chemistry, an Asian Journal
|April 10, 2025
Summary
We synthesized sequence-controlled polychalcogenophenes using catalyst-transfer polycondensation. These novel conjugated copolymers, including P(SSe)b(3HT), show promise for organic electronics applications.
Area of Science:
- Polymer Science
- Organic Electronics
- Materials Chemistry
Background:
- Sequence-controlled conjugated polymers are crucial for advanced electronic applications.
- Polychalcogenophenes offer tunable electronic properties.
- Poly(3-hexylthiophene) (P3HT) is a well-studied conjugated polymer.
Purpose of the Study:
- To design and synthesize novel alternating block conjugated copolymers based on polychalcogenophenes.
- To achieve precise control over polymer architecture, including molecular weight, dispersity, and sequence.
- To investigate the solid-state structure and organic field-effect transistor (OFET) performance of these new materials.
Main Methods:
- Nickel-catalyzed Kumada polymerization for synthesizing block copolymers.
- Catalyst-transfer polycondensation (CTP) for precise sequence control.
- Nuclear Magnetic Resonance (NMR) spectroscopy for structural confirmation.
- Grazing-incidence wide-angle X-ray scattering (GIWAXS) for solid-state analysis.
- Organic field-effect transistor (OFET) measurements for device performance evaluation.
Main Results:
- Successfully synthesized three sequence-controlled polychalcogenophenes: P(SSe)b(3HT), P(STe)b(3HT), and P(SeTe)b(3HT).
- CTP enabled precise control over molecular weight, dispersity, block length, and main chain sequence.
- NMR confirmed high side chain regioregularity. GIWAXS indicated an edge-on orientation in the solid state.
- P(SSe)b(3HT) achieved a maximum hole mobility of 4.4 × 10⁻² cm² V⁻¹ s⁻¹.
- P(STe)b(3HT) demonstrated a high hole mobility of 2.9 × 10⁻² cm² V⁻¹ s⁻¹, notable for tellurophene-containing polymers.
Conclusions:
- The developed CTP method allows for the precise synthesis of sequence-controlled polychalcogenophenes.
- These novel block copolymers exhibit promising performance in OFET applications.
- The findings open new avenues for designing functional conjugated polymers with tailored properties.
Related Concept Videos
01:26Thermal and Photochemical Electrocyclic Reactions: Overview
2.3K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.3K
01:18Aromatic Hydrocarbon Cations: Structural Overview
2.6K
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
Removing one hydrogen from the intervening CH2 group...
2.6K
01:17Thermal Electrocyclic Reactions: Stereochemistry
1.9K
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
1.9K
01:00Characteristics and Nomenclature of Homopolymers
2.9K
Polymers that are made up of identical monomer units are called homopolymers. Only one repeating unit is involved in the construction of the homopolymer structure. For example, as depicted in Figure 1, polypropylene is a homopolymer constituted of propylene monomers. Here, the only repeating unit in the polymer chain is propylene.
2.9K
02:37Disubstituted Cyclohexanes: cis-trans Isomerism
11.7K
Depending upon the different spatial orientation of the substituents, the disubstituted cycloalkanes exhibit two types of stereoisomers. The cis isomers have the substituents on the same side of the ring, whereas the trans isomers have the substituents on the opposite sides. These stereoisomers exhibit different physical properties and cannot be interconverted without breaking the carbon-carbon bonds.
In cyclohexane, the substituents can occupy different positions generating distinct isomers....
In cyclohexane, the substituents can occupy different positions generating distinct isomers....
11.7K
01:26Photochemical Electrocyclic Reactions: Stereochemistry
1.8K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.8K