Electron Acceptor Research Articles

Side Chain Enabling High-Performance Nonfused Ring Electron Acceptor with Controlled Aggregation Behavior

Side Chain Enabling High-Performance Nonfused Ring Electron Acceptor with Controlled Aggregation Behavior

Electron Sponge Effect by Dynamic-Regulated Electron Self-Flow toward Coupled Electrochemical Ammonia Synthesis.

A dynamic-regulated Pd-Fe-N electrocatalyst was effectively constructed with electron-donating and back-donating effects, which serves as an efficient engineering strategy to optimize the electrocatalytic activity. The designed PdFe3/FeN features a comprehensive electrocatalytic performance toward the nitrogen reduction reaction (NRR, yield rate of 29.94 μg h-1 mgcat-1 and FE of 38.43% at -0.2 V vs RHE) and oxygen evolution reaction (OER, 308 mV at 100 mA cm-2). Combining in situ ATR-FTIR, XAS, and DFT results, the role of the interstitial-N-dopant-induced electron sponge effect has been significantly elucidated in strengthening the electrocatalytic NRR process. Specifically, the introduction of a N dopant, an electron acceptor, initiates the generation of robust Lewis-acidic Fe sites, facilitating free N2 capture and bonding. Simultaneously, after NH3 adsorption, the N dopant can back-donate electrons to Fe sites, strengthening the NH3 deportation through weakening the Lewis acidity of Fe centers. Besides, the electron-deficient Fe sites contribute to the reconstruction of FeOOH, the real active species during the OER, which accelerates the four-electron reaction kinetics. This research offers a perspective on electrocatalyst design, potentially facilitating the evolution of advanced material engineering for efficient electrocatalytic synthesis and energy storage.

Control of Dynamic Chirality in Donor-Acceptor Fluorophores.

Very recently, the control of dynamic chirality has emerged as a powerful strategy to design chiral functional materials. In this context, we describe herein a molecular design in which a tethered configurationally stable binaphthyl chiral unit efficiently controls the dynamic chirality of donor-acceptor fluorophores, involving diverse indolocarbazoles as electron donors and terephthalonitrile as an electron acceptor. The high conformational discrimination in such a molecular system suggested by density functional theory calculations is experimentally probed using electronic and vibrational circular dichroism and confirmed by the crystallization of these chiral molecules in gel and their single crystal X-ray diffraction analysis. In addition to extending the scope of dynamic chirality control to donor-acceptor fluorophores, this work also highlights the positive effect of the configurationally stable chiral inductor on the magnitude of the dissymmetry factors of the active dynamically chiral fluorophores, both in ground and excited states, through chiral perturbation.

Control of Dynamic Chirality in Donor‐Acceptor Fluorophores

Very recently, the control of dynamic chirality has emerged as a powerful strategy to design chiral functional materials. In this context, we describe herein a molecular design in which a tethered configurationally stable binaphthyl chiral unit efficiently controls the dynamic chirality of donor‐acceptor fluorophores, involving diverse indolocarbazoles as electron donors and terephthalonitrile as an electron acceptor. The high conformational discrimination in such a molecular system suggested by density functional theory calculations is experimentally probed using electronic and vibrational circular dichroism and confirmed by the crystallization of these chiral molecules in gel and their single crystal X‐ray diffraction analysis. In addition to extending the scope of dynamic chirality control to donor‐acceptor fluorophores, this work also highlights the positive effect of the configurationally stable chiral inductor on the magnitude of the dissymmetry factors of the active dynamically chiral fluorophores, both in ground and excited states, through chiral perturbation.

Impact of Donor and Acceptor Modification on TADF and Roll‐Off Behaviors in Solution Processed OLED

AbstractUp‐conversion of triplet into singlet exciton in the emitting layer is believed to be one of the ways that thermally activated delayed fluorescent (TADF) materials may employ to reduce triplet exciton density hence preventing device quenching by triplet excitons. Yet, two donor‐acceptor type molecules; 5‐(4‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)phenyl)‐12‐(3‐(triphenylsilyl) phenyl)‐5,12‐dihydroindolo[3,2‐a]carbazole (SiPhCzTrz) and 5‐phenyl‐12‐(4‐(4‐phenyl‐6‐(3‐(triphenylsilyl) phenyl)‐1,3,5‐triazin‐2‐yl)pheny‐l)‐5,12‐dihydroindolo [3,2‐a]carbazole (SiTrzPhCz), which exhibited different TADF properties depending on the relative positions of their electron donor unit (PhCz) and electron acceptor unit (Trz), show opposite behaviors. These materials are used as sensitizer in phosphorescent solution‐processed organic light emitting diodes (s‐OLEDs) showing moderately high current efficiencies of 19.3 and 20 cd/A, respectively. SiTrzPhCz exhibits stronger TADF properties compared to SiPhCzTrz; however, these stronger TADF characteristics lead to a more pronounced efficiency roll‐off, mainly due to the longer residence time of excitons in SiTrzPhCz, leading to exciton quenching. In contrast, due to their twisted structures, the efficiency roll‐off is efficiently suppressed, particularly for SiTrzPhCz, when both materials are used as hosts. Their twisted structures promote aggregate‐induced emission and prevent aggregation‐caused quenching. Further analysis of exciton dynamics reveals faster decay rate for both singlet and triplet densities in SiPhCzTrz compared to SiTrzPhCz, indicated by its higher fast prompt emission, kFRET and knrT.

A first-principles investigation into the adsorption behavior and deposition mechanism of boron-containing gases on Si(100) surfaces during chemical vapor deposition

Polysilicon serves as a primary raw material in the production of solar cells and semiconductors. However, its impurity content, particularly boron, poses significant challenges during the chemical vapor deposition (CVD) process. Therefore, it is essential to investigate the behavior of boron impurities during CVD. In this study, we conducted first-principles calculations to explore the adsorption behavior and deposition mechanism of boron-containing gases (BCl3, BHCl2, B2H6) on the Si(100) surface. We considered different adsorption sites and performed a systematic analysis of various adsorption systems' adsorption energy, charge transfer, and electronic properties. Our findings indicate that BCl3, BHCl2, and B2H6 molecules undergo dissociative chemisorption at specific adsorption sites. Moreover, charge transfer analysis confirms that each of these adsorbed molecules functions as an electron acceptor. Subsequent analyses, including total charge density (TCD), charge density difference (CDD), total density of states (TDOS), and projected density of states (PDOS), collectively underscore the robust electronic interactions between the gaseous molecules and the Si(100) surface. Through the computation of transition states and energy barriers across three potential reaction pathways, we identify a predominant sequence: BCl3→BCl2+Cl→BCl+Cl→B+Cl, that governs boron impurity formation on the Si(100) surface during CVD. Our work elucidates the underlying microscopic mechanisms of boron-containing gas adsorption and deposition in the CVD context.

Multi-Functional AIE Phototheranostic Agent Enhancing αPD-L1 Response for Oral Squamous Cell Carcinoma Immunotherapy.

Oral squamous cell carcinoma (OSCC) represents a prevalent head and neck malignancy with surgical intervention as the primary clinical option. Immunotherapy, particularly immune checkpoint blockade (ICB) targeting PD-1/PD-L1 shows great promise but is impeded by the immunosuppressive tumor microenvironment and low PD-L1 expression in OSCC. Herein, the "all-in-one" phototherapeutic nanoparticles (TSD NPs) are reported with balanced reactive oxygen species and photothermal conversion capacity for combined photoimmunotherapy and ICB immunotherapy against OSCC. A novel electron acceptor, 3-(dicyanomethylene)-2,3-dihydrobenzothiophene-1,1-dioxide (DTM), is introduced to develop the phototherapeutic agent with aggregation-induced emission (AIE) feature and NIR-II fluorescence centered at 1000nm. Benefiting from the AIE feature and the DTM acceptor, the resultant TSD NPs also exhibit strong type I reactive oxygen species (ROS) generation and high photothermal conversion efficiency (45.3%), which can profoundly induce immunogenic cell death (ICD), activate cytotoxic T lymphocytes, and convert the immunosuppressive tumor microenvironment into an immune-supportive one. Additionally, TSD NPs upregulate the PD-L1 expression on OSCC cells, thus enhancing the efficacy of combined treatment with αPD-L1 ICB immunotherapy. This results show that the synergistic treatment of TSD NPs and αPD-L1 effectively eradicates solid OSCC tumors without adverse effects on normal tissues, proving a novel and promising strategy for OSCC management.

Porphyrins on acid: kinetics of the photoinduced-protonation of tetrakis(4-carboxyphenyl)-porphyrin.

Free-base porphyrins can be protonated, which significantly impacts their electronic and excited state properties. While excited state dynamics are well explored for either neutral or fully protonated porphyrins, the intermediate region has not yet been explored, although their potential implications for photocatalytic reactions are evident. This study explores how partial protonation affects the nature and properties of photoexcited states of tetrakis(4-carboxyphenyl)porphyrin (TCPP) using steady-state and nanosecond transient absorption spectroscopy. Global-fit analysis of the decay curves revealed the formation of a protonated excited triplet state from the neutral triplet state, as well as the long lifetimes of these species of up to 120 μs. The photoexcited triplet state of TCPP functions as a photobase, which was confirmed by computational analysis of the electron density of the exited states showing increased nucleophilicity at the unprotonated nitrogen atoms of the porphyrin core. These findings indicate that photoinduced protonated excited triplet states can function as electron acceptors with anodically shifted redox potentials, opening new pathways for porphyrin-based photoreactions.

A novel method to evaluate insulation performance of SF6 alternative gases based on modified GIPF-Local properties model

Abstract The development of structure-activity relationships (SAR) emerges as a crucial strategy to establish the correlations between molecular micro-parameters and the macroscopic dielectric strength, thus markedly improving the gases screening efficiency. However, conventional prediction approaches have failed to characterize the molecule electronegativity accurately, resulting in inadequate prediction precision within extensive gas databases. To address this limitation, we have devised an insulation prediction method that incorporates corrections based on molecular local properties, including local ionization energy and local electron affinity. They enable us to determine both the electron acceptance and donation capacity of the whole molecular orbital electron cloud: a more accuracy assessment of electronegativity. Compared with previous method, our enhanced approach combined local properties with structural and GIPF parameters. It has yielded substantial improvements based on an extensive database comprising 91 gases, as evidenced by an increase in the correlation coefficient from 0.848 to 0.969. Utilizing the modified GIPF-Local properties model, over ten potential gases were found and categorized according to their application. This innovative screening strategy provides crucial insights for exploration and design of new eco-friendly gases as substitute for SF6 used in high-voltage power equipment.

Boosting photocatalytic efficiency and nonlinear optical response of graphitic carbon nitride by infusing carbon nanotubes

Nanostructured materials are widely studied for their light-driven physical and chemical processes, which are key to their potential in photophysical applications. We introduce a one-pot solid-state pyrolysis technique for the synthesis of graphitic carbon nitride/carbon nanotube (g-C3N4/CNT) composites. The formation of the composite was characterized through X-ray diffraction, scanning and transmission electron microscopy, and X-ray photoelectron spectroscopy. Notably, UV-vis diffuse reflectance spectroscopy indicated a reduction in the bandgap of pure g-C3N4 from 2.6 eV to 2.35 eV with the incorporation of 0.5 wt% CNT. The nonlinear optical transmission of the samples was analyzed at 532 nm using the open-aperture Z-scan technique employing 5 ns laser pulses, revealing a twelve-fold increase in the two-photon absorption coefficient (b) for g-C3N4/CNT0.5 compared to pristine g-C3N4. Remarkably, g-C3N4/CNT0.5 showed enhanced photocatalytic efficiency in degrading bisphenol A (BPA), with the kinetic constant (k) being ten times higher than that of pure g-C3N4. The improved photocatalytic performance of g-C3N4/CNT0.5 is attributed to the presence of CNTs, which act as effective electron acceptors and transfer channels, significantly enhancing the separation of photogenerated charge carriers in g-C3N4, as evidenced by the decreased intensity in the photoluminescence spectrum.

Rational Molecular Design of Phenanthroimidazole-Based Fluorescent Materials toward High-Efficiency Deep-Blue OLEDs by Molecular Isomer Engineering.

Organic light-emitting diodes (OLEDs) have been extensively investigated in full-color displays and energy-saving lighting owing to their unique advantages. However, deep-blue OLEDs based on nondoped emitting layers with a satisfactory external quantum efficiency (EQE) are still rare for applications. In this work, six hot exciton materials, PPIM-12F, PPIM-22F, PPIM-13F, PPIM-23F, PPIM-1CN, and PPIM-2CN, are designed and synthesized via an isomer engineering design strategy and their photophysical properties and OLED performance are systematically investigated. These emitters all possess wide band gaps (3.53-3.69 eV), hybrid local and charge transfer (HLCT) characteristics, and good thermal stabilities. The C2 series compounds, PPIM-22F, PPIM-23F, and PPIM-2CN, all show redder emission peaks than the N1 series counterparts of PPIM-12F, PPIM-13F, and PPIM-1CN. In addition, the LUMO energy levels decrease consecutively in the sequence of PPIM-22F < PPIM-23F < PPIM-2CN and are all lower than their respective N1 series position isomers of PPIM-12F, PPIM-13F, and PPIM-1CN. The CV measurements indicate that such a design strategy renders the fine-tuning of LUMO energy levels, and the incorporation of electron acceptors at the extended C2 position of the PI unit is a better choice to improve the electron injection ability. Theoretical simulations indicate that they may harvest the triplet exciton through an upper-level reverse intersystem crossing process, which decreases the gathering of triplet excitons and allows the OLEDs to be fabricated by nondoping technology. Among them, PPIM-22F with a difluorobenzene substituent at the C2 position manifests the best performance in OLEDs, which exhibits the maximum EQE of 7.87% and Commission Internationale de ĺEclairage (CIE) coordinates of (0.16, 0.10). This work demonstrates an effective strategy for considerable improvement in device performance by a subtle change in the molecular structure through isomer engineering.

Microbial Ecology of Nitrate-, Selenate-, Selenite-, and Sulfate-Reducing Bacteria in a H2-Driven Bioprocess.

A hydrogen (H2)-based membrane biofilm reactor (H2-MBfR) can reduce electron acceptors nitrate (NO3-), selenate (SeO42-), selenite (HSeO3-), and sulfate (SO42-), which are in wastewaters from coal mining and combustion. This work presents a model to describe a H2-driven microbial community comprised of hydrogenotrophic and heterotrophic bacteria that respire NO3-, SeO42-, HSeO3-, and SO42-. The model provides mechanistic insights into the interactions between autotrophic and heterotrophic bacteria in a microbial community that is founded on H2-based autotrophy. Simulations were carried out for a range of relevant solids retention times (0.1 to 20 days) and with adequate H2-delivery capacity to reduce all electron acceptors. Bacterial activity began at an ∼0.6-day SRT, when hydrogenotrophic denitrifiers began to accumulate. Selenate-reducing and selenite-reducing hydrogenotrophs became established next, at SRTs of ∼1.2 and 2 days, respectively. Full nitrate, selenate, and selenite reductions were complete by an SRT of ∼5 days. Sulfate reduction began at an SRT of ∼10 days and was complete by ∼15 days. The desired goal of reducing nitrate, selenate, and selenite, but not sulfate, was achievable within an SRT window of 5 to 10 days. Autotrophic hydrogenotrophs dominated the active biomass, but non-active solids were a major portion of the solids, especially for an SRT ≥ 5 days.

Synergy of Ag and Interfacial Oxygen Vacancies on TiO2 for Highly Efficient Photocatalytic Production of H2O2.

Photocatalytic H2O2 production stands as a promising sustainable technology for chemical synthesis. However, rapid charge recombination and limited oxygen adsorption by photocatalysts often limit its efficiency. Herein, we demonstrate that the synergy of Ag and interfacial oxygen vacancies on TiO2 could overcome these challenges. The optimized Ag/TiO2-50 photocatalyst achieved an impressive H2O2 production rate of 12.9 mmol h-1 g-1 and maintained a steady-state concentration of 12.8 mM, significantly outperforming most TiO2-based photocatalysts documented in the literature. Detailed mechanistic studies, aided by TAS, in situ X-ray photoelectron spectroscopy (XPS), and in situ electron paramagnetic resonance (EPR) techniques, indicate that the oxygen vacancies at the Ag-TiO2 interface act as an interfacial hole trap, inducing a directional hole transfer. This, coupled with Ag acting as an electron acceptor, synergistically boosts the electron-hole separation. Additionally, the increased amount of oxygen vacancies at the Ag-TiO2 interface of Ag/TiO2-50 leads to enhanced O2 adsorption, thus contributing to its superior catalytic performance. This study provides valuable insights into interfacial traps in the charge transfer process and highlights the potential of interface regulation for achieving efficient photocatalytic conversion.

Microfluidic Platform for Semiconductor and MOF Integrated Photocatalysts: A Review over Synthesis Approaches and Applications

AbstractThe synergy of integrating semiconductors and MOF photocatalysts is the chief motive for this review paper. This merit has been combined with the microfluidic platforms, which are the cutting‐edge technology of synthesis. The microfluidic synthesis of semiconductors and MOF photocatalysts are categorized according to morphology and linker, respectively. Enhancing the effectiveness of photocatalysis comes along with adding a proper amount of electron acceptor or hole scavenger, combing electrochemical with photocatalytic degradation, and optimizing the photocatalyst band gap. Moreover, approaches for improving photocatalytic activity of MOFs can be classified as functionalization of organic linkers/metal centers, sensitization, incorporation of nanoparticles, and hybridization with semiconductors. Finally, the current applications of microfluidic devices, from the detection of water quality parameters to the elimination of water contaminants, have been addressed.

Systems biology of electrogenic Pseudomonas putida - multi-omics insights and metabolic engineering for enhanced 2-ketogluconate production

BackgroundPseudomonas putida KT2440 has emerged as a promising host for industrial bioproduction. However, its strictly aerobic nature limits the scope of applications. Remarkably, this microbe exhibits high bioconversion efficiency when cultured in an anoxic bio-electrochemical system (BES), where the anode serves as the terminal electron acceptor instead of oxygen. This environment facilitates the synthesis of commercially attractive chemicals, including 2-ketogluconate (2KG). To better understand this interesting electrogenic phenotype, we studied the BES-cultured strain on a systems level through multi-omics analysis. Inspired by our findings, we constructed novel mutants aimed at improving 2KG production.ResultsWhen incubated on glucose, P. putida KT2440 did not grow but produced significant amounts of 2KG, along with minor amounts of gluconate, acetate, pyruvate, succinate, and lactate. 13C tracer studies demonstrated that these products are partially derived from biomass carbon, involving proteins and lipids. Over time, the cells exhibited global changes on both the transcriptomic and proteomic levels, including the shutdown of translation and cell motility, likely to conserve energy. These adaptations enabled the cells to maintain significant metabolic activity for several weeks. Acetate formation was shown to contribute to energy supply. Mutants deficient in acetate production demonstrated superior 2KG production in terms of titer, yield, and productivity. The ∆aldBI ∆aldBII double deletion mutant performed best, accumulating 2KG at twice the rate of the wild type and with an increased yield (0.96 mol/mol).ConclusionsBy integrating transcriptomic, proteomic, and metabolomic analyses, this work provides the first systems biology insight into the electrogenic phenotype of P. putida KT2440. Adaptation to anoxic-electrogenic conditions involved coordinated changes in energy metabolism, enabling cells to sustain metabolic activity for extended periods. The metabolically engineered mutants are promising for enhanced 2KG production under these conditions. The attenuation of acetate synthesis represents the first systems biology-informed metabolic engineering strategy for enhanced 2KG production in P. putida. This non-growth anoxic-electrogenic mode expands our understanding of the interplay between growth, glucose phosphorylation, and glucose oxidation into gluconate and 2KG in P. putida.

Charge separation in a copper(I) donor-chromophore-acceptor assembly for both photoanode and photocathode sensitization.

A copper(I) donor-chromophore-acceptor triad bearing 1,8-napthalenemonoimide as the electron acceptor and triphenylamine as the electron donor was synthesized. Photophysical and electrochemical characterization suggest stepwise photoinduced charge separation upon excitation of the copper(I)-based metal-to-ligand charge transfer (MLCT) transition. Analyses of femtosecond transient absorption data of the triad show that intersystem crossing from the 1MLCT to the 3MLCT state is followed by two electron-transfer steps with time constants of 20 ps and 722 ps yielding a presumed final charge-separated state with a radical cation on the donor and radical anion on the acceptor that has an 18 ns lifetime in acetonitrile. Finally, this triad was anchored onto n-type (ZnO) and p-type (NiO) semiconductor surfaces to construct a photoanode and photocathode respectively. Successful photocurrent generation from both electrodes upon white light illumination confirms the potential utilization of such systems in dye-sensitized photoelectrochemical cells.

Polymer Based on Asymmetrically Halogenated Benzotriazole Enables High Performance Organic Solar Cells Prepared in Nonhalogenated Solvent.

Halogenation on the A unit of the D-π-A-type polymer donor has been proven as an effective strategy to improve the performance of organic solar cells (OSCs). Compared with fluorination, chlorination usually increases the open-circuit voltage because of the downward shift of energy levels, but decreases the charge transport ability due to the large steric hindrance of the chlorine atom. We reported herein a method to balance the energy loss and charge transport through asymmetric halogenation on the benzotriazole (BTA) unit of the polymer. The designed PE3-FCl based on the BTA unit containing fluorine and chlorine atoms rendered the highest power conversion efficiency (PCE) of 17.83% when eC9-2Cl-γ and o-xylene were used as the electron acceptor and solvent, respectively. The performance is obviously higher than that of the polymer PE3 containing a difluorinated BTA unit (16.65%) and polymer PE3-2Cl with dichlorinated BTA (14.65%) due to the manipulated morphology by preaggregation, improved and more balanced charge carrier transport, and reduced recombination loss. Notably, this PCE is a breakthrough for the BTA-based polymers processed by nonhalogenated solvent. This work gives deep insight into the asymmetric halogenation of polymer donors for high-performance green solvent-processed OSCs.

Enhanced Efficiency of Dye-Sensitized Solar Cells by Controlled Co-Adsorption Self-Assembly of Dyes.

Single dyes typically exhibit limited light absorption in dye-sensitized solar cells (DSSCs). Thus, cosensitization using two or more dyes to enhance light-harvesting efficiency has been explored; however, the aggregation of dyes can adversely affect electron injection capabilities. This study focused on the design and synthesis of three dyes with a common carbazole donor for DSSCs: DZ102, TZ101, and JM102. JM102 broadens the absorption spectrum by replacing the benzoic acid electron acceptor of TZ101 with acetylenic benzoic acid. A cosensitized DSSC device based on CO-1 [DZ102:TZ101 = 1:1 (50 μM:50 μM)] achieved a short-circuit current density of 19.4 mA/cm2 and a power conversion efficiency of 10.9%. For the first time, the molecular interactions between the dyes in the photoanode were demonstrated using cyclic voltammetry, which revealed the presence of intermolecular forces. Adsorption kinetics further indicated that these forces promoted the self-assembly of dyes during adsorption, which resulted in a cosensitization adsorption amount greater than the sum of the individual dye adsorptions. This study provides novel insights into the selection of cosensitizing dyes for DSSCs.

Phe265 of the D1 protein is required to stabilize plastoquinone binding in the QB-binding site of photosystem II in Synechocystis sp. PCC 6803

In Photosystem II electrons from water splitting pass through a primary quinone electron acceptor (QA) to the secondary plastoquinone (QB). The D2 protein forms the QA-binding site and the D1 protein forms the QB-binding site. A non-heme iron sits between QA and QB resulting in a quinone-Fe-acceptor complex that must be activated before assembly of the oxygen-evolving complex can occur. An extended loop (residues 223–266) between the fourth (helix D) and fifth (helix E) helices of the D1 protein activates forward electron transfer via a conformational change that stabilizes a bidentate bicarbonate ligand to the non-heme iron while simultaneously stabilizing the binding of QB. We show that positioning of D1:Phe265 to provide a hydrogen bond to the distal oxygen of QB is required for forward electron transfer. In addition, mutations targeting D1:Phe265, resulted in a 50 mV decrease in the QB/QB– midpoint potential.

Efficient thermally activated delayed fluorescence materials from symmetric anthraquinone derivatives for high-performance red OLEDs

Constructing efficient red thermally activated delayed-fluorescence (TADF) materials for high-performance organic light-emitting diodes (OLEDs) remains challenging due to the formidable barrier of energy gap law. In this work, a design strategy of connecting two donor units to the adjacent positions of electron acceptor is proposed for creating red luminescent materials, and four Y-shaped TADF molecules consisting of strong electron-withdrawing anthraquinone (AQ) acceptor and triphenylamine or acridine-based donors are designed and synthesized. They exhibit strong red emissions (604−618 nm) in toluene solutions and orange/red emissions (566−608 nm) with good photoluminescence quantum yields (43−68%) in doped films, and enjoy small singlet-triplet energy gaps (0.02−0.10 eV) and fast reverse intersystem crossing processes (1.5–7.3 × 105 s−1), which are attributed to the unique Y-shape structure. A maximum external quantum efficiency of 19.5% with an electroluminescence peak at 616 nm is achieved for AQ-PTPA-based red doped device, representing the highest level for red TADF-OLEDs based on AQ acceptor in the literature. This work can provide guidance for the design of efficient red delayed-fluorescence molecules for the application in OLEDs.