Enhanced Photocatalytic Performance of Donor–Acceptor-Type Polymers Based on a Thiophene-Contained Polycyclic Aromatic Unit

Abstract

Donor–acceptor (D–A)-type photocatalysts containing the polycyclic aromatic donor (BTT-CPP) and nonpolycyclic aromatic donor (TTB-CPP) are designed and synthesized. Their physicochemical properties are thoroughly investigated. The photocatalytic hydrogen generation experiments show that both polymers exhibit distinct photocatalytic performance. BTT-CPP displays an attractive hydrogen evolution rate (HER) of 37,866 μmol g–1 h–1 without further addition of the metal co-catalyst, one of the highest values reported for organic photocatalysts. The optimal HER of TTB-CPP is 8466 μmol g–1 h–1. These results highlight the important role of the donor unit on the performance of D–A-type photocatalysts and demonstrate that thiophene-contained polycyclic aromatic unit BTT is an excellent donor unit for high HER photocatalysts.

Transition-Metal-Free Synthesis of Conjugated Microporous Polymers via Amine-Catalyzed Suzuki-Miyaura Coupling Reaction

“…Therefore, it is very potential to be a new approach for synthesis of CMPs. Among the conventional C-C coupling methods, the Suzuki-Miyaura cross-coupling reaction is important in the CMP synthesis, and has been widely adopted to construct CMPs as heterogeneous catalysts, [24][25][26][27] organic photocatalysts, [28][29] lightharvesting antenna 30 or photo-luminescent materials. 19 It is a C-C bond formation reaction via coupling an aryl-boron monomer with an aryl halide monomer, 31 which conventionally uses Pd based catalysts, i.e.…”

Click-based conjugated microporous polymers as efficient heterogeneous photocatalysts for organic transformations

“…After the copper promoted polymerization, an electronacceptor unit, 1,2,3-triazole, 39 was introduced into the polymer skeletons. Since thiophene is a widely used electrondonor unit, 29,[41][42][43][44] the obtained Ta-Ths could be employed as donor-acceptor type photocatalysts. The polymers were found insoluble in water or some common organic solvents, such as 1,4-dioxane, dichloromethane (CH 2 Cl 2 ), chloroform (CHCl 3 ), ethyl acetate (EtOAc), acetonitrile (CH 3 CN), methanol (CH 3 OH), tetrahydrofuran (THF), N,Ndimethylformamide (DMF) and dimethyl sulfoxide (DMSO).…”

Structure evolution of thiophene-containing conjugated polymer photocatalysts for high-efficiency photocatalytic hydrogen production

“…The high HER of 33.07 mmol h −1 g −1 for the bare PyTP-2 under visible light outperforms that of most previously reported organic photocatalysts (Table S1). For example, the triazine-based polymer of triazine-Th-CPP exhibited an HER of 4.43 mmol h −1 g −1 under visible-light irradiation [43], the D-A conjugated polymer of BTT-CPP showed an HER of 12.63 mmol h −1 g −1 under visible light [40], the sulfone-based conjugated copolymer of PS-5 gave an HER of 7.5 mmol h −1 g −1 under visible light illumination [48], and the linear conjugated polymer P2 showed an HER of 10.85 mmol h −1 g −1 [20]. Moreover, a direct comparison of PyTP-2 with the counterpart of CP1 produced from pyrene and bithiophene demonstrates that PyTP-2 shows a much higher HER (33.07 mmol h −1 g −1 ) than CP1 (15.97 mmol h −1 g −1 ) under visible light illumination [7].…”

“…Generally, an efficient polymer photocatalyst should have a broad spectral absorption range, fast transmission ability of charge carriers, high separation capability of light-induced electrons and holes, and high hydrophilicity, which could be controlled by the structural design and component tuning on the macromolecular chains. For example, it has been proved that constructing a donoracceptor (D-A) molecular structure could be an efficient strategy to promote the photocatalytic activity due to the enhanced dissociation efficiency of photo-induced electrons and holes in the D-A polymer photocatalyst [39][40][41][42]. In addition, dibenzothiophene-S,S-dioxide (BTDO), possessing strong electronwithdrawing ability, planar structure and high hydrophilicity, has been widely studied as an electron acceptor for improving photocatalytic performance of polymeric photocatalysts.…”

“…In addition, dibenzothiophene-S,S-dioxide (BTDO), possessing strong electronwithdrawing ability, planar structure and high hydrophilicity, has been widely studied as an electron acceptor for improving photocatalytic performance of polymeric photocatalysts. For instance, a BTDO-containing conjugated polymer of BTT-CPP exhibited a high hydrogen evolution rate (HER) of 37.88 mmol h −1 g −1 under broadband irradiation and an HER of 12.63 mmol h −1 g −1 under visible light [40]. The triazine-based polymer of triazine-Ph-CPP showed high HER values of 16.28 and 3.50 mmol h −1 g −1 upon broadband light and visible light irradiation, respectively [43].…”