Ester-Substituted Photovoltaic Polymers With Tuned Aryl Side Chains

Solution Overview

Problem

Existing ester-substituted benzo[2,1-b:3,4-b']dithiophene polymers for organic photovoltaics achieve only moderate power conversion efficiencies, necessitating the development of novel polymers with improved performance.

Innovation Solution

The method involves combining Me3Sn—X—SnMe3 and Me3Sn—X′—SnMe3 to form a polymer with specific substituents and aryl groups, allowing for variations in molecular structure and composition to enhance performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If conventional ester-substituted benzo[2,1-b:3,4-b']dithiophene polymers are used, then the device structure is simple and manufacturing is straightforward, but the power conversion efficiency is limited to moderate levels (4.74-5.14%)

Engineering Contradiction:

Improveease of manufactureVSAvoidpower conversion efficiency

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent employs composite polymer structures combining benzo[2,1-b:3,4-b′]dithiophene cores with various ester substituents (methyl ester, ethyl ester, propyl ester, butyl ester) and aromatic side chains. This composite approach allows optimization of both processability and photovoltaic performance, achieving power conversion efficiencies exceeding 5.14% while maintaining ease of manufacture through solution processing.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent systematically varies key molecular parameters including ester chain length (methyl to butyl), aromatic group composition (phenyl, naphthyl, anthryl), and polymer backbone structure. These parameter changes enable tuning of HOMO/LUMO energy levels, absorption coefficients, and charge transport properties, thereby improving power conversion efficiency beyond conventional polymers while preserving manufacturing simplicity.

Inventive Principle:

Principle #35Parameter changes

2Ease of manufacture

If polymer structure is simplified for ease of manufacture, then manufacturing becomes straightforward, but power conversion efficiency remains moderate at best

Engineering Contradiction:

Improveease of manufactureVSAvoidpower conversion efficiency

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent systematically varies key molecular parameters including ester chain length (methyl to butyl), aromatic group composition (phenyl, naphthyl, anthryl), and polymer backbone structure. These parameter changes enable tuning of HOMO/LUMO energy levels, absorption coefficients, and charge transport properties, thereby improving power conversion efficiency beyond conventional polymers while preserving manufacturing simplicity.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs composite polymer structures combining benzo[2,1-b:3,4-b′]dithiophene cores with various ester substituents (methyl ester, ethyl ester, propyl ester, butyl ester) and aromatic side chains. This composite approach allows optimization of both processability and photovoltaic performance, achieving power conversion efficiencies exceeding 5.14% while maintaining ease of manufacture through solution processing.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS12319767B2Forming ester-substituted polymers for organic photovoltaics

Publication Date: 2025.06.03 PHILLIPS 66 CO

AI summary

A method comprised of combiningMe3Sn—X—SnMe3 to form a solution containing a polymerIn this polymer R, R′, and R″ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups; and X is selected from aryl groups.