Bending the Rule: Naphthobisthiadiazole-Based Terpolymers with Both High Solubility and Crystallinity for Organic Photovoltaics
Journal
ACS Applied Polymer Materials
Journal Volume
6
Journal Issue
5
Date Issued
2024-03-08
Author(s)
Chou, Li Hui
Chen, Fengkun
Nakano, Kyohei
Yamanaka, Kodai
Mikie, Tsubasa
Saito, Masahiko
Tajima, Keisuke
Osaka, Itaru
Abstract
Achieving a good balance between the crystallinity and solubility is of great importance in the design of π-conjugated polymers. Here, we synthesized a series of terpolymers in which small fractions of a planar V-shaped fused ring, triphenyleno[1,2-c:7,8-c′]bis([1,2,5]thiadiazole) (TPTz), are incorporated into the linear-shaped backbone of a highly crystalline polymer based on naphtho[1,2-c:5,6-c′]bis([1,2,5]thiadiazole) (NTz), PNTz4T. Due to the “bending” structure induced by the TPTz unit, the terpolymers had greatly improved solubility by about 5-9 times compared to the linear-shaped PNTz4T. In particular, the terpolymers preserved the crystallinity of PNTz4T to a considerable extent with a higher fraction of face-on oriented domains in films. As a result, the highly solution-processable terpolymers exhibited high photovoltaic performances and slightly outperformed PNTz4T. Our results indicate that the incorporation of a V-shaped unit into a linearly shaped polymer is a good strategy to develop π-conjugated polymers with high solubility and crystallinity.
Subjects
crystallinity | nonfullerene | organic photovoltaics | organic semiconductors | solubility | π-conjugated polymers
SDGs
Type
journal article