Thiophene Units Research Articles

Rational design of g-C3N4-based photocatalysts with intramolecular donor-acceptor structures for deep oxidation of emerging organic micropollutants

An in-situ route for the fabrication of intramolecular electron donor-acceptor (D-A) structured g-C3N4 photocatalysts is developed by the preorganization of urea with the precursor of electron donor units, such as 4-iodobenzaldehyde, 5-bromo-2-thiophenaldehyde and 5-bromo-2-furaldehyde, followed by thermal polymerization. In the resulting benzene unit-, thiophene unit- and furan unit-based D-A structured g-C3N4 photocatalysts, namely, BHCNx, SCNx, and OCNx, the incorporated electron donor units (i.e., benzene units, thiophene units and furan units) link with the electron acceptors (i.e., heptazine units) through CN and CN covalent bonds. In comparison of bulk g-C3N4, all D-A structured g-C3N4 display notably enhanced visible-light photocatalytic oxidation activity in the degradation of emerging organic micropollutants, p-nitrophenol (PNP) and methylparaben (MPB), in which the apparent first-order kinetic constant of the optimized BHCN2, SCN2, and OCN2 is 1.6, 3.0 and 6.8 times higher than bulk g-C3N4 for PNP degradation and 1.9, 3.4 and 2.6 times higher than bulk g-C3N4 for MPB degradation. Importantly, the micropollutants can be not only degraded but also mineralized completely. The catalysts are also robust in the removal of mixed emerging organic micropollutants in pharmaceutical wastewater, exhibiting potential of dealing with organic micropollutants in wastewater. Mechanism studies reveal that the unique intramolecular charge transfer process in the catalysts enhances visible-light harvesting capacity, boosts directional transfer of the photogenerated charges and increases adsorption towards oxygen molecules. These collective improvements can maximum utilization the photogenerated electrons and holes to yield plentiful reactive oxygen species for deep oxidization of the pollutants.

Controllable Supramolecular Aggregation of Hydroazaheptacene Tetraimides and Derivatives in Nonpolar and Polar Solvents.

Rational control of the supramolecular aggregation of π-conjugated molecules plays an important role in determining their optoelectronic properties and applications. Here, we report a systematic study of the factors, including solvent polarity, concentration, and surfactants, that affect the aggregation behavior of a brominated hydroazaheptacene tetraimide (HATI) and its thiophene-substituted derivative, Th-HATI, as near-infrared fluorophores, in both nonpolar and polar solvents. The thermal stability of the aggregates is also studied by monitoring their optical absorption against temperature change. Our results indicate that the aggregation of HATI is highly sensitive to the solvent polarity. Moreover, the average aggregation number of HATI inside the colloidal nanoparticles formed in aqueous media can be controlled by surfactants. The substitution of the bromo groups in HATI by thiophene units induces a slight blue shift of the optical absorption, enhanced crystallinity, distinct aggregation behavior in both nonpolar and polar solvents, and improved thermal stability. The multifacet understanding of the supramolecular aggregation of these systems may offer insight for other π-conjugated molecular chromophores with various optoelectronic properties and applications.

Asymmetrical Diketopyrrolopyrrole Derivatives with Improved Solubility and Balanced Charge Transport Properties.

The diketopyrrolopyrrole (DPP) unit represents one of the building blocks more widely employed in the field of organic electronics; in most of the reported DPP-based small molecules, this unit represents the electron acceptor core symmetrically coupled to donor moieties, and the solubility is guaranteed by functionalizing lactamic nitrogens with long and branched alkyl tails. In this paper, we explored the possibility of modulating the solubility by realizing asymmetric DPP derivatives, where the molecular structure is extended in just one direction. Four novel derivatives have been prepared, characterized by a common dithyenil-DPP fragment and functionalized on one side by a thiophene unit linked to different auxiliary electron acceptor groups. As compared to previously reported symmetric analogs, the novel dyes showed an increased solubility in chloroform and proved to be soluble in THF as well. The novel dyes underwent a thorough optical and electrochemical characterization. Electronic properties were studied at the DFT levels. All the dyes were used as active layers in organic field effect transistors, showing balanced charge transport properties.

Synthesis, characterization, and electronic transport properties of o-carborane-bridged thiophene derivatives

Here, α- or β-thiophene-substituted derivatives bridged by an o-carborane group were synthesized. Scanning tunneling microscope break junction techniques have revealed that the thiophene anchoring groups form a single-molecule junction with an Au electrode. Flicker noise analysis suggests the existence of through-space transmission pathways between the thiophene units. Furthermore, the electronic coupling of the β-thiophene substituted molecule with the electrode is found to be more stable, resulting in a 70 % increase in conductance compared to the α-isomer counterpart.These findings offer valuable insights for the design and development of o-carborane-based molecules, underscoring the significance of molecular backbones and substitution patterns on their electrical transport properties.

Enhanced Intersystem Crossing in a Thiohelicene

AbstractThe photophysics of a helicene derivative in which two benzene units are replaced by thiophene units (thiohelicene, 6H) was studied by steady state and transient absorption and emission spectroscopies covering time ranges from femtoseconds to minutes. Efficient intersystem crossing (ISC) to the triplet state was observed, by far exceeding that of the parent helicene and the corresponding oxo‐helicene. Quantum chemical calculations indicate that the helical distortion and the heavy atom effect of sulfur cooperate in promoting spin‐orbit coupling, and that the most efficient decay channel involved the T2 or even the T3 state. These insights can help in the design of more efficient triplet sensitizers for many applications.

Prominent Intrinsic Proton Conduction in Two Robust Zr/Hf Metal-Organic Frameworks Assembled by Bithiophene Dicarboxylate.

To date, developing crystalline proton-conductive metal-organic frameworks (MOFs) with an inherent excellent proton-conducting ability and structural stability has been a critical priority in addressing the technologies required for sustainable development and energy storage. Bearing this in mind, a multifunctional organic ligand, 3,4-dimethylthiophene[2,3-b]thiophene-2,5-dicarboxylic acid (H2DTD), was employed to generate two exceptionally stable three-dimensional porous Zr/Hf MOFs, [Zr6O4(OH)4(DTD)6]·5DMF·H2O (Zr-DTD) and [Hf6O4(OH)4(DTD)6]·4DMF·H2O (Hf-DTD), using solvothermal means. The presence of Zr6 or Hf6 nodes, strong Zr/Hf-O bonds, the electrical influence of the methyl group, and the steric effect of the thiophene unit all contribute to their structural stability throughout a wide pH range as well as in water. Their proton conductivity was fully examined at various relative humidities (RHs) and temperatures. Creating intricate and rich H-bonded networks between the guest water molecules, coordination solvent molecules, thiophene-S, -COOH, and -OH units within the framework assisted proton transfer. As a result, both MOFs manifest the maximum proton conductivity of 0.67 × 10-2 and 4.85 × 10-3 S·cm-1 under 98% RH/100 °C, making them the top-performing proton-conductive Zr/Hf-MOFs. Finally, by combining structural characteristics and activation energies, potential proton conduction pathways for the two MOFs were identified.

Intrinsically Stretchable Organic Thermoelectric Polymers Enabled by Incorporating Fused-Ring Conjugated Breakers.

While research on organic thermoelectric polymers is making significant progress in recent years, realization of a single polymer material possessing both thermoelectric properties and stretchability for the next generation of self-powered wearable electronics is a challenging task and remains an area yet to be explored. A new molecular engineering concept of "conjugated breaker" is employed to impart stretchability to a highly crystalline diketopyrrolepyrrole (DPP)-based polymer. A hexacyclic diindenothieno[2,3-b]thiophene (DITT) unit, with two 4-octyloxyphenyl groups substituted at the tetrahedral sp3-carbon bridges, is selected to function as the conjugated breaker that can sterically hinder intermolecular packing to reduce polymers' crystallinity. A series of donor-acceptor random copolymers is thus developed via polymerizing the crystalline DPP units with the DITT conjugated breakers. By controlling the monomeric DPP/DITT ratios, DITT30 reaches the optimal balance of crystalline/amorphous regions, exhibiting an exceptional power factor (PF) value up to 12.5 µW m-1 K-2 after FeCl3-doping; while, simultaneously displaying the capability to withstand strains exceeding 100%. More significantly, the doped DITT30 film possesses excellent mechanical endurance, retaining 80% of its initial PF value after 200 cycles of stretching/releasing at a strain of 50%. This research marks a pioneering achievement in creating intrinsically stretchable polymers with exceptional thermoelectric properties.

Enhancement of thermoelectric performance of thienoisoindigo based D‐A conjugated polymers through the incorporation of 3,4‐ethylenedioxythiophene as donor unit

AbstractWith the good planarity of conjugated backbone and high charge carrier mobilities, thienoisoindigo (TIIG)‐based polymers show great potential in organic electronic devices. In this work, two TIIG‐based D‐A conjugated polymers (PTIIG‐3T and PTIIG‐2T‐EDOT) were designed and synthesized, which exhibit high lying highest occupied molecular orbital (HOMO) energy level and can be facilely doped by FeCl3. Compared with PTIIG‐3T, one thiophene unit in the donor building block is replaced by 3,4‐ethylenedioxythiophene (EDOT) in PTIIG‐2T‐EDOT, and PTIIG‐2T‐EDOT shows a higher HOMO level with slightly higher coplanarity than PTIIG‐3T, which induce an enhancement in electrical conductivity after oxidation doping. After proper doping, doped PTIIG‐2T‐EDOT film achieved a higher TE power factor of 17.9 μW m−1 K−2 than that of PTIIG‐3T due to its higher conductivity. The results indicate that TIIG unit is a promising building block for future high‐performance conjugated polymers for thermoelectric applications, and incorporation of the EDOT unit into D‐A conjugated polymers could be an effective way to develop high performance thermoelectric polymers.

Developing Benzodithiophene-Free donor polymer for 19.36% efficiency Green-Solvent-Processable organic solar cells

In this work, a newly benzodithiophene-free D-A polymer donor, named PDTP-BDD, was developed for realizing green-solvent processed high-performance OSCs. By bridging two electron-rich unit of dithieno[3,2-b:2′,3′-d]pyridin-5(4H)-one (DTP) and electron-deficient benzo[1,2-c:4,5c′]dithiophene-4,8-dione (BDD) with thiophene units, PDTP-BDD possesses high absorption in the short wavelength range and a deep HOMO energy level. The rigid building blocks also make PDTP-BDD has strong aggregation and poor solubility in common halogen-free solvents (such as o-xylene) at room temperature, but it is readily dissolved and disaggregated at high temperature (120 °C). After cooling down to a lower temperature (60 °C), PDTP-BDD self-assembled and pre-aggregated slowly in the solution at a long time. By employing a delayed processing strategy in the layer-by-layer processed OSCs (LbL-OSCs), an optimized fibril network of the underling layer was realized, enabling the permeation of acceptor into the donor network. The optimized PDTP-BDD/L8-BO-based LbL-OSCs realized a high PCE of 18.42 %. By adding a small amount of D18 to further optimize the PDTP-BDD fibril network, an impressive PCE of 19.36 % was achieved finally in the resulting ternary LbL-OSCs, which is the highest value for OSCs processed by halogen-free solvents.

Conjugated polymers with thiazolothiazole as the acceptor unit for high performance organic solar cells

In this study, we used a simple, cost-effective, and high-yield synthetic route to successfully synthesize two thiazolothiazole-based wide-bandgap donor polymers, namely TTZ and ANTTZ. We systematically investigated how the solubility, absorption and photoelectric properties of the materials were influenced by the position of ester group at the thiophene unit as π-bridge. Theoretical calculations, UV–vis spectroscopy and GIWAXS results revealed that TTZ possesses planar molecular backbone and higher crystallinity. Ultimately, with BTP-ec9-4F as the acceptor, the TTZ based devices can achieve an impressive power conversion efficiency (PCE) of 13.96%; whereas the ANTTZ based devices can give a PCE of only 3.07%. This research underscores the effectiveness of a cost-efficient donor material synthesis route and highlights the crucial influence of the side chain position on crystallinity of the polymer, offering a new direction for designing low-cost, high-efficiency photovoltaic materials.

Design of non-fused ring electron acceptors with “embracing-type” side chains for organic solar cells

Backbone planarity is an inherent structural feature for fused ring electron acceptors and one of important prerequisites for their high photovoltaic performance. However, for non-fused ring electron acceptors (NFREAs), it is a challenging task to achieve it. In this work, two NFREAs (Ph2TIC and BT2TIC) containing thiophene-benzene-thiophene or thiophene-benzothiadiazole-thiophene three non-fused aromatic rings in central scaffold were designed with an attempt to use a pair of 2,4,6-triisopropylphenyl substituents (referred as “embracing”-type side chains) at 3,3′-positions of the two thiophene units to lock the backbone in a planar conformation. X-ray crystallography revealed that Ph2TIC has a quasi-planar backbone, whereas BT2TIC shows a twisted one, but both tend to form two-dimensional layered arrays through intermolecular π-π stacking involving terminal acceptor moieties. UV–vis light-absorption spectroscopy showed that both compounds have similar optoelectronic properties either in dilute solutions or in solid film state, thus confirming the conformation-lock function of the “embracing”-type side chains. While for photophysical properties, BT2TIC displays a red-shifted broader light absorption spectrum as compared to Ph2TIC due to the introduction of an additional acceptor moiety in the structure. Ph2TIC and BT2TIC were evaluated as the acceptor materials in organic solar cells in combination with PM6, a typical donor polymer, and delivered the optimized power conversion efficiencies of 4.31 % and 3.78 %, respectively. Although the photovoltaic performances are modest, the work provides a new thought for maintaining the backbone planarity in NFREAs and would be useful in their future design.

Wide bandgap polymer donors with an acceptor1-π-acceptor2-π configuration for efficient polymer solar cells

To maximize the photovoltaic performance of polymer solar cells (PSCs), polymer donors and nonfullerene acceptors (NFAs) should be designed with complementarily optical and electronic properties as well as desirable morphological features. Currently, high-performance polymer donors are mainly constructed by alternating copolymerization of electron-rich (D) and electron-deficient (A) units. Here, we demonstrate that acceptor1-π-acceptor2-π (A1-π-A2-π)-type polymer donors constructed by copolymerization of two different A units can achieve comparable photovoltaic properties with those of D-π-A-π-type counterparts. By using the ladder-type 4,10-bis(2-hexyldecyl)-thieno[2ˊ,3ˊ:5,6]pyrido[3,4-g]thieno-[3,2-c]isoquinoline-5,11-dione as A1 unit, difluorobenzotriazole or benzodithiophene-4,8-dione as A2 unit, and thiophene unit as the π bridge, two A1-π-A2-π-type copolymers, P03 and P07, are successfully synthesized. Due to the weakened intramolecular charge-transfer effect, P03 and P07 exhibit wide bandgaps of 1.88 and 1.74 eV, respectively. In combination with the NFA of L8-BO, the P03:L8-BO-based blend shows superior crystallinity and uniform phase-separated morphology thereby leading to a higher power conversion efficiency (PCE) of 15.03 % in comparison with the P07:L8-BO-based blend which shows a PCE of 9.84 %. Notably, the 15.03 % efficiency is by far the highest value for PSCs based on A1-π-A2-π-type polymer donors. These results provide useful guidance for the future design of high-performance donor copolymers for PSCs.

One‐Pot Rh(III)‐Catalyzed Twofold C−H Activation/Oxidative Annulation of N‐Arylpyrroles with Alkynes to Fluorescent Ullazines

AbstractA range of densely functionalized ullazines have been synthesized by a one‐pot Rh(III)‐catalyzed twofold C−H activation/oxidative annulation of N‐arylpyrroles with alkynes. Electrophilic bromination at 5‐ or 5,7‐ positions of the EWG‐substituted ullazine core offers an interesting single or double entry for further extended functionalization. Mechanistic considerations suggest two complementary paths, EWG‐assisted and SEAr, for the C−H activations. All ullazines exhibit strong fluorescence emissions. Ullazines bearing thiophene and triarylamine units at 5‐ and 5,7‐ positions show a significant bathochromic shift in their emission spectra, attributed to the more extended electronic circuits present.

Multimodal phototherapy agents target lipid droplets for near-infrared imaging-guided type I photodynamic/photothermal therapy

The construction and optimization of a single phototherapeutic agent with photoluminescence, type I photodynamic therapy (PDT), and photothermal therapy (PTT) functions remain challenging. In this study, we aimed to design and synthesize four donor–acceptor (D-A) type aggregation-induced emission molecules: PSI, TPSI, PSSI, and TPSSI. We employed phenothiazine as an electron donor and 1,3-bis(dicyanomethylidene)indan as a strong electron acceptor in the synthesis process. Among them, TPSSI exhibited efficient type I reactive oxygen species generation, high photothermal conversion efficiency (45.44 %), and near-infrared emission. These observations can be attributed to the introduction of a triphenylamine electron donor group and a thiophene unit, which resulted in increased D–A strengths, a reduced singlet-triplet energy gap, and increased free intramolecular motion. TPSSI was loaded into bovine serum albumin to prepare biocompatible TPSSI nanoparticles (NPs). Our results have indicated that TPSSI NPs can target lipid droplets with negligible dark toxicity and can efficiently generate O2•− in hypoxic tumor environments. Moreover, TPSSI NPs selectively targeted 4T1 tumor tissues and exhibited a good PDT-PTT synergistic effect in vitro and in vivo. We believe that the successful preparation of multifunctional phototherapeutic agents will promote the development of efficient tumor diagnosis and treatment technologies. Statement of SignificanceThe construction of a single phototherapeutic agent with photoluminescence, type I photodynamic therapy, and photothermal therapy functions, and its optimization remain challenging. In this study, we construct four donor–acceptor aggregation-induced emission molecules using phenothiazine as an electron donor and 1,3-Bis(dicyanomethylidene)indan as a strong electron acceptor. By optimizing the molecular structure, an integrated phototherapy agent with fluorescence imaging ability and high photodynamic / photothermal therapy performance was prepared. We believe that the successful preparation of multifunctional phototherapeutic agents will promote the development of efficient tumor diagnosis and treatment technology.

2,5-dichloro-3,4-diiodothiophene as a versatile solid additive for high-performance organic solar cells

Volatile solid additive (SA) with diverse chemical structures has been proved to be an alternative to prepare high-efficient organic solar cells (OSCs). While, various organic photovoltaic materials raise challenges in selecting suitable SAs during the device optimization. Herein, based on the simple and commonly used thiophene unit, we proposed a perhalogenated 2,5-dichloro-3,4-diiodothiophene (SA-T5) as the SA for the device optimizations. As results, the capacity of SA-T5 in optimizing molecular packings of small-molecular acceptor L8-BO, dimeric acceptor DL8, and polymeric acceptor PY-DT based blend films has been demonstated. Their optimized morphologies assisted by SA-T5 contribute to the suppressed charge recombination and enhanced charge transportation, resulting in their improved short-circuit current density and fill factor, simultaneously. In comparsion with as-cast devices, SA-T5-treated devices showed significantly improved power conversion efficiencies (PCEs) of 18.8 % for PM6:L8-BO, 17.8 % for PM6:DL8, and 17.6 % for PM6:PY-DT, respectively. Furthermore, the potential of SA-T5 in obtaining high-performance ternary OSCs was also confirmed, for example, a 18.1 % efficiency was realized in PM6:DL8:L8-BO based device. To our knowledge, the performance of these SA-T5-treated devices reaches the best results of different acceptor-based OSCs. Importantly, this work provides a rare and successful case to develop versatile SAs for high-performance OSCs.

Optimized Incorporation of Furan into Diketopyrrolopyrrole-Based Conjugated Polymers for Organic Field-Effect Transistors.

Flexible electronics have received considerable attention in the past decades due to their promising application in rollable display screens, wearable devices, implantable devices, and other electronic applications. In particular, conjugated polymers are favored for flexible electronics due to their mechanical flexibility and potential for solution-processed fabrication techniques, such as blade-coating, roll-to-roll printing, and high-throughput printing allowing for high-performance transistor devices. Thiophene is the prevailing conjugated unit to construct these conjugated polymers due to its favorable electronic properties. On the other hand, furans are among the few conjugated moieties that are easily derived from bio renewable resources. To promote sustainability, we selectively introduced furan into the conjugated backbone of a high-mobility polymer scaffold and systematically studied the effect on the microstructure and charge transport. We show that partially and selectively replacing thiophene units with furan can yield nearly comparable performance compared to the all-thiophene polymer. This strategy offers an improvement in the sustainability of the polymer by incorporating bio-sourced furan without sacrificing the high-performance characteristics. Meanwhile, polymers with incorrect or complete furan incorporation show reduced mobilities. This work serves to develop coherent structure-morphology-performance relationships; such knowledge will establish guidelines for the future development of sustainable, furan-based conjugated materials.

Carbazol-benzothiadiazole based D–A–D mesogens: Self-assembly and photophysical characteristics

Three carbazole(C)-benzothiadiazole(B) based D-A-D mesogens CBC/n (n = 12, 16) and CTBTC/16 containing terminal N-trialkoxylbenzyl carbazoles at both side of central benzothiadiazole core have been designed and synthesized. By inserting thiophene (T) unit between B and C units, the rigid core was elongated and the molecular conformation changed from twist to planar one, thereby the liquid crystal (LC) phase changed from SmA to Col/hex phase. Such molecular packings caused by inserting T unit remained in their organogels formed in organic solvents. The long-core compound CTBTC/16 containing T unit with a more planar and tighter π-π packing structure showed a significant optical red shift and a stronger intramolecular charge transfer (ICT) effect than the short-core compounds CBC/n without thiophene unit. These compounds are all strong fluorescent in solution with fluorescence quantum yields (ΦF) ranging from 38 % to 86 %. But their solid fluorescence quantum yields (ΦFs) differ greatly with values of 43 %, 11 % and 0.6 % for CBC/12, CBC/16 and CTBTC/16 respectively. Further, short core compound CBC/12 with the highest ΦFs showed different ΦFs in its three different solid aggregation states. The application of the short twist core compound CBC/12 as white light-emitting diodes (LEDs) has been realized. The influence of the thiophene unit as well as the terminal alkyl chain length on self-assembly and ΦFs of these compounds is discussed.

Triazine Frameworks for the Photocatalytic Selective Oxidation of Toluene

AbstractInvestigations into the selective oxidation of inert sp3 C−H bonds using polymer photocatalysts under mild conditions have been limited. Additionally, the structure‐activity relationship of photocatalysts often remains insufficiently explored. Here, a series of thiophene‐based covalent triazine frameworks (CTFs) are used for the efficient and selective oxidation of hydrocarbons to aldehydes or ketones under ambient aerobic conditions. Spectroscopic methods conducted in situ and density functional theory (DFT) calculations revealed that the sulfur atoms within the thiophene units play a pivotal role as oxidation sites due to the generation of photogenerated holes. The effect of photogenerated holes on photocatalytic toluene oxidation was investigated by varying the length of the spacer in a CTF donor‐acceptor based photocatalyst. Furthermore, the manipulation of reactive oxygen species was employed to enhance selectivity by weakening the peroxidative capacity. As an illustrative example, this study successfully demonstrated the synthesis of a precursor of the neurological drug AMG‐579 using a photocatalytic protocol.

Triazine Frameworks for the Photocatalytic Selective Oxidation of Toluene.

Investigations into the selective oxidation of inert sp3 C-H bonds using polymer photocatalysts under mild conditions have been limited. Additionally, the structure-activity relationship of photocatalysts often remains insufficiently explored. Here, a series of thiophene-based covalent triazine frameworks (CTFs) are used for the efficient and selective oxidation of hydrocarbons to aldehydes or ketones under ambient aerobic conditions. Spectroscopic methods conducted in situ and density functional theory (DFT) calculations revealed that the sulfur atoms within the thiophene units play a pivotal role as oxidation sites due to the generation of photogenerated holes. The effect of photogenerated holes on photocatalytic toluene oxidation was investigated by varying the length of the spacer in a CTF donor-acceptor based photocatalyst. Furthermore, the manipulation of reactive oxygen species was employed to enhance selectivity by weakening the peroxidative capacity. As an illustrative example, this study successfully demonstrated the synthesis of a precursor of the neurological drug AMG-579 using a photocatalytic protocol.

Donor-acceptor type conjugated porous polymers based on benzotrithiophen and triazine derivatives: Effect of linkage unit on photocatalytic water splitting

Donor-acceptor conjugated polymers have received significant attention as the most promising photocatalysts for efficient photocatalytic hydrogen production (PHP). Nonetheless, achieving high photocatalytic PHP performance relies on molecular framework design and the judicious selection of different structural units. Herein, benzotrithiophene (BTT) and triazine derivatives were used as the basic units of organic polymers, and two conjugated porous polymers (CPPs) named as CP1 and CP2 were successfully synthesized by Stille coupling reaction. Compared with benzene as the linkage unit of triazine, it is evident that the incorporation of the thiophene unit in CP2 broadens its light response range, and promotes the generation of electrons/holes induced by light. Density functional theory (DFT) calculations and femtosecond transient absorption(fs-TA) spectroscopy reveal that CP2 effectively inhibits the photogenerated electron-hole pair recombination and promotes carrier transport. Remarkably, CP2 with Pt co-catalyst exhibited a notably superior PHP performance compared with that of CP1 polymer, which achieved an impressive hydrogen evolution rate (HER) of 21702.4 μmol/g/h, surpassing CP1 by approximately 3.7 times. This work provides a new tactic for enhancing the intrinsic PHP activity and reveals the underlying mechanism for the enhanced photocatalytic activity by regulating the different structural units of the donor-acceptor conjugated polymers.