Related Experiment Video
Updated: Jan 8, 2026
05:48
Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
8.5K
High-Performance Nonfused Ring Electron Acceptors with Well-Controlled Branching Position of the Alkoxy Side Chain
Zhenyu Yang1, Xiangmeng Deng1, Gendi Zhang1
1Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875, China.
ACS Applied Materials & Interfaces
|December 16, 2025
Summary
Side-chain engineering in nonfused ring electron acceptors (NFREAs) significantly improves organic solar cell (OSC) performance. Optimized NFREA design leads to enhanced solubility, morphology, and charge transport, achieving a 16.29% power conversion efficiency.
Area of Science:
- Materials Science
- Organic Electronics
- Photovoltaics
Background:
- Side-chain engineering is crucial for tuning the properties of electron acceptors.
- Properties like aggregation, solubility, charge transport, and film morphology are affected by side chains.
- Nonfused ring electron acceptors (NFREAs) are a key component in organic solar cells (OSCs).
Purpose of the Study:
- To design and synthesize novel NFREAs by adjusting alkyl side chain branching and position.
- To investigate the structure-property relationships of these NFREAs.
- To optimize NFREA design for enhanced organic solar cell performance.
Main Methods:
- Synthesis of three NFREAs: XY-OC24, XY-OC6, and XY-OC2C4, with varying side chains.
- Characterization of solubility, aggregation behavior, and blend film morphology.
- Fabrication and testing of organic solar cells (OSCs) using the synthesized NFREAs.
Main Results:
- The NFREA XY-OC24, with specific alkoxy side chains, exhibited enhanced solubility due to increased steric hindrance.
- The blend film of XY-OC24 showed reduced domain sizes, a bicontinuous fibrous interpenetrating network, and face-on orientation.
- These morphological improvements facilitated charge transport, reduced recombination, and enhanced charge extraction.
Conclusions:
- Side-chain engineering is a powerful strategy for optimizing NFREA properties and OSC performance.
- The NFREA XY-OC24 achieved a high power conversion efficiency of 16.29% in OSCs.
- This work provides insights into NFREA design principles for advancing OSC technology.
Related Concept Videos
01:11ortho–para-Directing Activators: –CH3, –OH, –NH2, –OCH3
7.2K
All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...
7.2K
02:38Electrophilic Addition to Alkynes: Halogenation
9.9K
Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
9.9K
02:24Acid-Catalyzed Ring-Opening of Epoxides
8.6K
Epoxides that are three-membered ring systems are more reactive than other cyclic and acyclic ethers. The high reactivity of epoxides originates from the strain present in the ring. This ring strain acts as a driving force for epoxides to undergo ring-opening reactions either with halogen acids or weak nucleophiles in the presence of mild acid. The acid catalyst converts the epoxide oxygen, a poor leaving group, into an oxonium ion, a better leaving group, making the reaction feasible. The...
8.6K
02:26Base-Catalyzed Ring-Opening of Epoxides
9.9K
Due to their highly strained structures, epoxides can readily undergo ring-opening reactions through nucleophilic substitution, either in the presence of an acid or a base. The nucleophilic substitution reactions in the presence of acid are called acid-catalyzed ring-opening reactions, and nucleophilic substitution reactions in the presence of a base are called base-catalyzed ring-opening reactions. Epoxides undergo base-catalyzed ring-opening reactions in the presence of a strong nucleophile...
9.9K
01:24ortho–para-Directing Deactivators: Halogens
6.5K
Halogens are ortho–para directors. They are more electronegative than carbon. Therefore, as ring substituents, they can withdraw electrons through the inductive effect and deactivate the aromatic ring towards electrophilic substitution. Halogens also have an electron-donating resonance effect on the ring, which influences the orientation of the incoming electrophile. If an electrophile attacks at the ortho or the para position, the halogen donates electrons and stabilizes the intermediate...
6.5K
01:26Limitations of Friedel–Crafts Reactions
6.7K
Several restrictions limit the use of Friedel–Crafts reactions. First, the halogen in the alkyl halide must be attached to an sp3-hybridized carbon for the Friedel–Crafts reactions to occur. Vinyl or aryl halides do not react since the carbocations formed are unstable under the reaction conditions. Second, Friedel–Crafts alkylation is susceptible to carbocation rearrangement, and the major products obtained have a rearranged carbon skeleton. In contrast, the acylium ion is...
6.7K