Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

ortho–para-Directing Activators: –CH3, –OH, –&NoBreak;NH2, –OCH3

ortho–para-Directing Activators: –CH₃, –OH, –⁠NH₂, –OCH₃

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...

Cycloaddition Reactions: MO Requirements for Photochemical Activation

Cycloaddition Reactions: MO Requirements for Photochemical Activation

Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.

Photochemical Electrocyclic Reactions: Stereochemistry

Photochemical Electrocyclic Reactions: Stereochemistry

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

[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement

[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement

The Cope rearrangement is classified as a [3,3] sigmatropic shift in 1,5-dienes, leading to a more stable, isomeric 1,5-diene. The reaction involves a concerted movement of six electrons, four from two π bonds and two from a σ bond, via an energetically favorable chair-like transition state.

Stability of Substituted Cyclohexanes

Stability of Substituted Cyclohexanes

This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...

Phase II Reactions: Methylation Reactions

Phase II Reactions: Methylation Reactions

Methylation is a phase II biotransformation process involving the attachment of a methyl group to a substrate. Enzymes known as methyltransferases orchestrate this reaction.
The mechanism of methylation unfolds in two stages. The first stage sees a methyltransferase enzyme facilitating the transfer of a methyl group from S-adenosylmethionine (SAM) to the substrate, forming S-adenosylhomocysteine (SAH). The second stage involves further metabolism of SAH into homocysteine, which can be recycled...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

"Steric-Locking" Polymer Acceptor Enabled 20.53% Efficiency With Suppressed Energetic Disorder and Enhanced Mechanical Robustness in Green-Solvent Processed All-Polymer Solar Cells.

Advanced materials (Deerfield Beach, Fla.)·2026

Same author

Decoupling Processing-Morphology-Stability Relationships Enables 19.65% Organic Solar Cells With Exceptional Photostability.

Small (Weinheim an der Bergstrasse, Germany)·2026

Same author

Electrostatic Potential Tuning by Low-Volatility Halogenated Additive: Boosting PTQ10-Based Binary OPV to Near 20% Efficiency with High Scalability.

Advanced materials (Deerfield Beach, Fla.)·2026

Same author

Molecular dynamics evidence for bidirectional feedback between PFAS and humic acid during composting: Interaction mechanisms, conformational reorganization, and diffusion regulation.

Journal of hazardous materials·2026

Same author

Quantum well-inspired energy level design in multicomponent organic solar cells for improved energy loss management.

Materials horizons·2026

Same author

Early thermal pulses drive interfacial pre-aging and plastisphere pre-shaping: An overlooked pre-conditioning pathway in PLA microplastic aging during composting.

Journal of hazardous materials·2026

Search research articles

Related Experiment Video

Updated: Sep 16, 2025

Morphology Control for Fully Printable Organic–Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer

Morphology Control for Fully Printable Organic–Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer

Published on: January 10, 2017

Precise Modulation of Reorganization Energy through Methyl Substitution for High Performance Organic Solar Cells.

Li Chen¹, Chaoyue Zhao¹, Joshua Yuk Lin Lai¹

¹Department of Chemistry and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, The Hong Kong University of Science and Technology, Hong Kong, 999077, P. R. China.

Advanced Science (Weinheim, Baden-Wurttemberg, Germany)

|July 7, 2025

Summary

Designing new quinoxaline acceptors with methyl and halogen groups minimizes energy loss in organic solar cells (OSCs). BQx-MeCl achieved 19.2% power conversion efficiency (PCE) by reducing reorganization energy and improving charge transport.

Keywords:

methyl substitution organic solar cells quinoxaline reorganization energy small molecule acceptor

More Related Videos

Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance

Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance

Published on: February 27, 2017

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Published on: March 19, 2017

Related Experiment Videos

Last Updated: Sep 16, 2025

Morphology Control for Fully Printable Organic–Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer

Morphology Control for Fully Printable Organic–Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer

Published on: January 10, 2017

Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance

Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance

Published on: February 27, 2017

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Published on: March 19, 2017

Area of Science:

Materials Science
Organic Electronics
Photovoltaics

Background:

Efficient charge transport and minimized energy loss are crucial for high-performance organic solar cells (OSCs).
Molecular design plays a key role in controlling material properties and device efficiency.

Purpose of the Study:

To design and synthesize novel quinoxaline-based electron acceptors with methyl and halogen substitutions.
To systematically investigate the impact of these substitutions on reorganization energy (λ) and film morphology.
To correlate molecular structure with charge transport properties and power conversion efficiency (PCE) in OSCs.

Main Methods:

Synthesis of quinoxaline-based electron acceptors (BQx-MeF, BQx-MeCl, BQx-MeBr).
Quantum chemical calculations to determine reorganization energy (λ) and understand electronic properties.
Fabrication and characterization of binary and ternary organic solar cells (OSCs).
Measurement of charge carrier mobilities and power conversion efficiency (PCE).

Main Results:

Methylation was found to effectively reduce reorganization energy (λ) by limiting structural relaxation.
BQx-MeCl demonstrated suppressed non-radiative recombination energy loss (ΔE_nr) and balanced electron/hole mobilities.
A power conversion efficiency (PCE) of 19.2% was achieved in a binary OSC device using BQx-MeCl.
In optimized ternary OSCs, BQx-MeCl further improved PCE to 19.6% due to enhanced molecular stacking and film morphology.

Conclusions:

Molecular design, specifically lowering reorganization energy (λ), is a critical strategy for minimizing energy losses in OSCs.
BQx-MeCl represents a promising electron acceptor material for developing high-efficiency organic solar cells.
Optimized molecular stacking and film morphology contribute significantly to improved device performance by reducing trap-assisted recombination.