Fengfeng Huang, Junyu Ma, Jiucheng Nie, Binbin Xu, Xiaoyu Huang, Guolin Lu, Mitchell A. Winnik, Chun Feng
{"title":"A Versatile Strategy toward Donor–Acceptor Nanofibers with Tunable Length/Composition and Enhanced Photocatalytic Activity","authors":"Fengfeng Huang, Junyu Ma, Jiucheng Nie, Binbin Xu, Xiaoyu Huang, Guolin Lu, Mitchell A. Winnik, Chun Feng","doi":"10.1021/jacs.4c08415","DOIUrl":null,"url":null,"abstract":"Living crystallization-driven self-assembly (CDSA) has emerged as an efficient strategy to generate nanofibers of π-conjugated polymers (CPNFs) in a controlled fashion. However, reports of donor–acceptor (D–A) heterojunction CPNFs are extremely rare. The preparation of these materials remains a challenge due to the lack of rational design guidelines for the D–A π-conjugated units. Herein, we report a versatile CDSA strategy based upon carefully designed D–A-<i>co</i>-oligomers in which electron-deficient benzothiadiazole (BT) or dibenzo[<i>b</i>,<i>d</i>]thiophene 5,5-dioxide (FSO) units are attached to the two ends of an oligo(<i>p</i>-phenylene ethynylene) heptamer [BT-OPE<sub>7</sub>-BT, FSO-OPE<sub>7</sub>-FSO]. This arrangement with the electron-deficient groups at the two ends of the oligomer enhances the stacking interaction of the A–D–A π-conjugated structure. In contrast, D–A–D structures with a single BT in the middle of a string of OPE units disrupt the packing. We employed oligomers with a terminal alkyne to synthesize diblock copolymers BT-OPE<sub>7</sub>-BT-<i>b</i>-P2VP and BT-OPE<sub>7</sub>-BT-<i>b</i>-PNIPAM (P2VP = poly(2-vinylpyridine), PNIPAM = poly(<i>N</i>-isopropylacrylamide)) and FSO-OPE<sub>7</sub>-FSO-<i>b</i>-P2VP and FSO-OPE<sub>7</sub>-FSO-<i>b</i>-PNIPAM. CDSA experiments with these copolymers in ethanol were able to generate CPNFs of controlled length by both self-seeding and seeded growth as well as block comicelles with precisely tunable length and composition. Furthermore, the D–A CPNFs with a BT-OPE<sub>7</sub>-BT-based core demonstrate photocatalytic activity for the photooxidation of sulfide to sulfoxide and benzylamine to <i>N</i>-benzylidenebenzylamine. Given the scope of the oligomer compositions examined and the range of structures formed, we believe that the living CDSA strategy with D–A-based co-oligomers opens future opportunities for the creation of D–A CPNFs with programmable architectures as well as diverse functionalities and applications.","PeriodicalId":49,"journal":{"name":"Journal of the American Chemical Society","volume":null,"pages":null},"PeriodicalIF":14.4000,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the American Chemical Society","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/jacs.4c08415","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Living crystallization-driven self-assembly (CDSA) has emerged as an efficient strategy to generate nanofibers of π-conjugated polymers (CPNFs) in a controlled fashion. However, reports of donor–acceptor (D–A) heterojunction CPNFs are extremely rare. The preparation of these materials remains a challenge due to the lack of rational design guidelines for the D–A π-conjugated units. Herein, we report a versatile CDSA strategy based upon carefully designed D–A-co-oligomers in which electron-deficient benzothiadiazole (BT) or dibenzo[b,d]thiophene 5,5-dioxide (FSO) units are attached to the two ends of an oligo(p-phenylene ethynylene) heptamer [BT-OPE7-BT, FSO-OPE7-FSO]. This arrangement with the electron-deficient groups at the two ends of the oligomer enhances the stacking interaction of the A–D–A π-conjugated structure. In contrast, D–A–D structures with a single BT in the middle of a string of OPE units disrupt the packing. We employed oligomers with a terminal alkyne to synthesize diblock copolymers BT-OPE7-BT-b-P2VP and BT-OPE7-BT-b-PNIPAM (P2VP = poly(2-vinylpyridine), PNIPAM = poly(N-isopropylacrylamide)) and FSO-OPE7-FSO-b-P2VP and FSO-OPE7-FSO-b-PNIPAM. CDSA experiments with these copolymers in ethanol were able to generate CPNFs of controlled length by both self-seeding and seeded growth as well as block comicelles with precisely tunable length and composition. Furthermore, the D–A CPNFs with a BT-OPE7-BT-based core demonstrate photocatalytic activity for the photooxidation of sulfide to sulfoxide and benzylamine to N-benzylidenebenzylamine. Given the scope of the oligomer compositions examined and the range of structures formed, we believe that the living CDSA strategy with D–A-based co-oligomers opens future opportunities for the creation of D–A CPNFs with programmable architectures as well as diverse functionalities and applications.
期刊介绍:
The flagship journal of the American Chemical Society, known as the Journal of the American Chemical Society (JACS), has been a prestigious publication since its establishment in 1879. It holds a preeminent position in the field of chemistry and related interdisciplinary sciences. JACS is committed to disseminating cutting-edge research papers, covering a wide range of topics, and encompasses approximately 19,000 pages of Articles, Communications, and Perspectives annually. With a weekly publication frequency, JACS plays a vital role in advancing the field of chemistry by providing essential research.