Π-conjugated Structure Research Articles

Porous organic cages for efficient gas selective separation and iodine capture

The enantiomeric porous organic cages, (R)/(S)-BTPOC, have been devised and prepared by means of dynamic covalent chemistry, using imine bond formation between bithiophene-based tetraaldehyde and cyclohexanediamine building blocks. These two cage molecules with porous interiors, stable aromatic backbones, and multiple electron-rich building units have been fully characterized by spectroscopy and single crystal X-ray diffraction studies. Self-assembly of BTPOC molecules provided porous crystalline materials with high CO2 adsorption of 265 cm3 g−1 under 760 mmHg and 196 K according to the physical gas sorption analysis. The guest-free cage shows distinct CO2, CH4, and N2 adsorption behaviors. Moreover, BTPOC is able to accommodate a large amount of I2 with a high uptake value of 3.21 g g−1, superior to almost all the porous molecular crystals reported thus far. This stable material has also excellent recyclability, keeping above 85% capacity when being activated for the fourth cycles. Mechanism investigations reveal the close association of the good adsorption ability with the abundant porosity, π-conjugated network structure, and high imine bonds content. The present work shows the great application potentialities of these microporous POCs.

Construction of an electrochemical aptasensor based on a carbazole-bearing porous organic polymer for rapid and ultrasensitive detection of penicillin

A carbazole-bearing porous organic polymer (POP) was successfully prepared by an efficient Friedel − Crafts coupling reaction of 2,4,6-tri(9H-carbazol-9-yl)-1,3,5-triazine and 2,4,6-tris(bromomethyl)mesitylene. The as-synthesized POP can load aptamers to fabricate an electrochemical aptasensor because of its high surface area, outstanding stability, and extended π-conjugation structure, which can rapidly monitor penicillin (PCL) with excellent sensitivity, high selectivity, fine reproducibility, and good stability. More importantly, the POP-based aptasensor can precisely detect trace PCL in various real samples.

N-contained organic carbonyl potassium salt with Mult-active sites as a High-capacity anode for Potassium-ion batteries

A novel organic 2,2′-bipyridine-5,5′-potassium dicarboxylate (K2C12H6N2O4) was designed and synthesized as an anode material in potassium-ion batteries. Multiple active sites and large π-conjugated plane molecular structure promote K2C12H6N2O4 to exhibit a high specific capacity of 840 mAh g−1 at 20 mA g−1, which exceed most of the reported K-storage anode materials.

Insights into the Mechanism of Elemental Mercury Adsorption on Graphitic Carbon Nitride: A Density Functional Theory Study

Recently, graphitic carbon nitride (g-C3N4) has been proven to be a novel and effective carbon-based adsorbent for elemental mercury (Hg0) removal in flue gas due to its peculiar π-conjugated electronic structure and chemical and thermal stability. However, the active sites and detailed reaction pathways occurring on the g-C3N4 surface are still unknown. Here, g-C3N4 nanoplates with abundant active edge sites (surface defects) are successfully prepared via a thermal polymerization method, which display good Hg0 adsorption ability. The adsorption behavior of Hg0 over g-C3N4 is further studied using quantum chemistry calculations based on density functional theory (DFT), aiming at gaining a better understanding of the Hg0 adsorption structures and bonding mechanisms on the g-C3N4 surface at the atomic level. The calculation results show that the adsorption of Hg0 on intact g-C3N4 surfaces is poor due to the stable chemical structure of intact g-C3N4 and lack of active electron orbitals. In contrast, g-C3N4 with surface defects, i.e., exposed C or N sites, possesses enhanced Hg0 adsorption ability probably owing to the unsaturated coordination bond environment and the formation of chemical bonds with mercury atoms at the defective sites. The location of defects also has a big influence on the mercury capture ability of g-C3N4. The exposed surface nitrogen is more favorable for mercury capture than the exposed surface carbon.

Caesium sites coordinated in Boron-doped porous and wrinkled graphitic carbon nitride nanosheets for efficient charge carrier separation and Transfer: Photocatalytic H2 and H2O2 production

This study reports the synthesis of a highly efficient visible-light-driven photocatalyst for hydrogen evolution and H2O2 production by manipulating the electronic band structure and surface properties of g-C3N4. Boron and caesium co-doped g-C3N4 porous and wrinkled nanosheets were nobly synthesized by using recrystallization of melamine in water in the presence of boric acid and CsCl followed by calcination and thermal etching. The prepared nanosheets showed an extremely porous and wrinkled structure with high surface area and edge sites. The optimized B, Cs co-doped g-C3N4 nanosheets exhibited a stable hydrogen evolution rate of 1,120 μmolg-1h−1 in the presence of triethanolamine, which is 7.7 times higher than that of the bulk. Moreover, this optimized structure showed a greatly increased hydrogen peroxide production rate of 113 μmolg-1h−1 compared to that (19 μmolg-1h−1) of the bulk GCN-B. Meanwhile, the optimized structure showed a high photooxidation ability toward RhB oxidation. This outstanding improvement in photocatalytic performance is attributed to the enhanced charge carrier mobility in the π-conjugated structure and increased accessible reaction sites for photocatalytic reactions originated from the synergetic effect of co-doping and formation of the porous and wrinkled nanosheets.

Temperature-modulated porous gadolinium micro-networks with hyperchrome-enhanced fluorescence effect

Porous gadolinium micro-networks with hyperchrome-enhanced fluorescence effect are prepared for white light-emitting diodes and highly-efficient peroxidase-like catalyst. • Gd-MNs with hyperchrome-enhanced fluorescence are prepared by a facile one-pot hydrothermal method. • Porous Gd-MNs with tunable porosity can be obtained by controlling the reaction temperature. • Porous Gd-MNs as the carrier can be well used for white light-emitting diodes and peroxidase-like catalyst. Porous and luminescent functional materials having well-controlled morphology are crucial in the field of adsorption, catalysis, and drug release. Herein, we propose the mechanism of hyperchrome-enhanced fluorescence (HEF) for the synthesis of highly fluorescent gadolinium micro-networks (Gd-MNs) via a facile one-pot hydrothermal treatment of almost non-luminescent Gd 3+ ions / citric acid (Gd 3+ /CA) complexes. It is found that after high-temperature polymerization, a strong π-π* transition occurs in the Gd-MNs, which significantly enhances the absorption of light. So, our proposed HEF effect as a new photoactivation strategy can efficiently improve the fluorescence (FL) emission of optical materials by creating a large π-conjugated structure. Surprisingly, the FL of Gd-MNs is 152 times higher compared to that of Gd 3+ /CA complexes. In particular, porous Gd-MNs (P-Gd-MNs) having tunable porosity can be obtained by changing the reaction temperature, as the formation of the porous structure is strongly dependent on the release of H 2 O molecules, coordinated with Gd 3+ ions. Because of their porous structure and good FL properties, P-Gd-MNs is an ideal material for white light-emitting diodes (WLEDs) with adjustable correlation color temperature, by embedding fluorescent carbon dots into their pores. Besides, P-Gd-MNs can also be transformed into a peroxidase-like catalyst by directly reducing the Cu 2+ ions of the porous surface. Moreover, Cu coated P-Gd-MNs can also be used for catalysing the degradation of rhodamine 6G dye with a degradation efficiency of about 100%. Hence, the facile synthesis of P-Gd-MNs opens new avenues for its potential applications in WLEDs fabrication and biocatalysis.

Bioinspired Applications of Porphyrin Derivatives.

Porphyrin derivatives are ubiquitous in nature and have important biological roles, such as in light harvesting, oxygen transport, and catalysis. Owing to their intrinsic π-conjugated structure, porphyrin derivatives exhibit characteristic photophysical and electrochemical properties. In biological systems, porphyrin derivatives are associated with various protein molecules through noncovalent interactions. For example, hemoglobin, which is responsible for oxygen transport in most vertebrates, consists of four subunits of a globular protein with an iron porphyrin derivative prosthetic group. Furthermore, noncovalently arranged porphyrin derivatives are the fundamental chromophores in light-harvesting systems for photosynthesis in plants and algae. These biologically important roles originate from the functional versatility of porphyrin derivatives. Specifically, porphyrins are excellent host compounds, forming coordination complexes with various metal ions that adds functionality to the porphyrin unit, such as redox activity and additional ligand binding at the central metal ion. In addition, porphyrins are useful building blocks for functional supramolecular assemblies because of their flat and symmetrical molecular architectures, and their excellent photophysical properties are typically utilized for the fabrication of bioactive functional materials. In this Account, we summarize our endeavors over the past decade to develop functional materials based on porphyrin derivatives using bioinspired approaches. In the first section, we discuss several synthetic receptors that act as artificial allosteric host systems and can be used for the selective detection of various chemicals, such as cyanide, chloride, and amino acids. In the second section, we introduce multiporphyrin arrays as mimics of natural light-harvesting complexes. The active control of energy transfer processes by additional guest binding and the fabrication of organic photovoltaic devices using porphyrin derivatives are also introduced. In the third section, we introduce several types of porphyrin-based supramolecular assemblies. Through noncovalent interactions such as metal-ligand interaction, hydrogen bonding, and π-π interaction, porphyrin derivatives were constructed as supramolecular polymers with formation of fiber or toroidal assembly. In the last section, the application of porphyrin derivatives for biomedical nanodevice fabrication is introduced. Even though porphyrins were good candidates as photosensitizers for photodynamic therapy, they have limitations for biomedical application owing to aggregation in aqueous media. We suggested ionic dendrimer porphyrins and they showed excellent photodynamic therapy (PDT) efficacy.

Synergy of semiconductor components of non-covalent functionalized (PdS doped)-G CdS NPs composite provide efficient photocatalytic water reduction under visible light

A new composite based on a few-layered pristine graphene, G, was prepared under mild conditions by adsorption of a functionalized pyrimidine derivative, Tren, followed by sequential precipitation of PdS and CdS NPs. The composite G-Tren-PdS-CdS showed high photocatalytic activity in water reduction providing a constant average H2 production of 2.3 mmol·g−1·h−1 during 24 h, which exceded 18.9 times that of the bare CdS. Structural analyses of the fresh and used phocatalyst revealed high robustness of the material. A systhematic study of the structure and optical properties of the materials revealed the pyrimidine-G moiety, G-Tren, behaves as a semiconductor with a band gap which can be finelly tuned through the control of the amount of adsorbed pyrimidine. The study also allowed to propose a reliable mechanism for the photocatalytic process. The excellent performance of the photocatalyst, in which CdS acts as electron provider for the hydrogen reduction and PdS and G-Tren moieties as cocatalysts, is attributed mainly to the complementary of the ranges of visible light absorption of the components, G-Tren, CdS and PdS, and to the possible role played by the arene basic centers provided by the unaltered π-conjugated structure of G, as reduction active sites.

Excited state quantum modulations in organic semiconductors

Organic semiconductors are formed by coupling organic molecules with π-conjugated structure through van der Waals interactions. Different from traditional inorganic semiconductors, such as silicon, the core element of organic semiconductors is carbon atom. Generally, in a π-conjugated organic molecule, carbon atoms are polymerized by sp or sp2 hybridization, forming small molecules or polymers due to the molecular size. Taking the polymer cis -polyacetylene as an example, each carbon atom has three 2sp2 hybrid orbitals in a plane and one 2p z orbital orthogonal to this plane. The 2sp2 orbitals give rise to three σ-bonds, two of which are formed with neighboring carbons and one with a hydrogen. The electron in the 2p z orbital of one carbon atom will be paired with the electron in the neighboring carbon’s 2p z orbital, such that this electron can be delocalized along the chain, denoted as π-electron. For such an organic molecule, according to the Peierls instability, it will be dimerized and form a single-double bond alternation lattice structure, behaving in a semiconductor character. Through doping, the conductivity of organic molecules can be greatly improved and become good conductors. This is the reason why the functional properties of organic molecules first attracted great attention in the 1970s, by which, Heeger, MacDiarmid and Shirakawa won the 2000 Nobel Prize in Chemistry. When organic molecules form solids, the packing of molecules will ultimately determine their functional properties and applications, such as organic polymer films and organic small molecule crystals. Over the past few decades, due to the flexibility and ease of processing, organic semiconductors have become very promising materials in functional devices, such as field-effect transistors, light-emitting diodes, solar cells, as well as organic spin valves. In general, the functional processes of these organic devices are closely related to the quantum dynamics of the formed excited states, including soliton, polaron, bipolaron, exciton, biexciton, charge transfer state, and trion, etc. These excited states are spatially localized due to the self-trapping effect of organic molecules, which arises from their strong electron-lattice interactions. Especially, these excited states behave in abundant and unusual charge-spin relations. For these reasons, the functional processes in organic devices are usually more unique and complex compared with conventional inorganic devices. To date, although many kinds of organic functional devices have been successfully developed, there are still many unsolved questions in their functional mechanisms. The excited state research is the key to solve these questions, and thus the core of organic semiconductor physics and device research. In view of this, through the combination of theoretical and experimental methods, we studied the quantum effects and modulation mechanisms of different excited states in organic semiconductors and their hetero structures. The main contents included are as follows: Quantum dynamics and field modulations for the photoexcitation, interfacial charge separation, and resonance energy transfer in organic photovoltaic systems; spin injection and transport in organic semiconductors, organic magnetoresistance effect, excited ferromagnetism, spin current and organic chiral spin effects. On the one hand, these studies greatly enrich the understanding for the physical phenomena and mechanisms in organic semiconductors; on the other hand, they should greatly promote the designs and applications of organic functional devices.

Nonconjugated Terpolymer Acceptors with Two Different Fused-Ring Electron-Deficient Building Blocks for Efficient All-Polymer Solar Cells.

The ternary polymerization strategy of incorporating different donor and acceptor units forming terpolymers as photovoltaic materials has been proven advantageous in improving power conversion efficiencies (PCEs) of polymer solar cells (PSCs). Herein, a series of low band gap nonconjugated terpolymer acceptors based on two different fused-ring electron-deficient building blocks (IDIC16 and ITIC) with adjustable photoelectric properties were developed. As the third component, ITIC building blocks with a larger π-conjugation structure, shorter solubilizing side chains, and red-shifted absorption spectrum were incorporated into an IDIC16-based nonconjugated copolymer acceptor PF1-TS4, which built up the terpolymers with two conjugated building blocks linked by flexible thioalkyl chain-thiophene segments. With the increasing ITIC content, terpolymers show gradually broadened absorption spectra and slightly down-shifted lowest unoccupied molecular orbital levels. The active layer based on terpolymer PF1-TS4-60 with a 60% ITIC unit presents more balanced hole and electron mobilities, higher photoluminescence quenching efficiency, and improved morphology compared to those based on PF1-TS4. In all-polymer solar cells (all-PSCs), PF1-TS4-60, matched with a wide band gap polymer donor PM6, achieved a similar open-circuit voltage (Voc) of 0.99 V, a dramatically increased short-circuit current density (Jsc) of 15.30 mA cm–2, and fill factor (FF) of 61.4% compared to PF1-TS4 (Voc = 0.99 V, Jsc = 11.21 mA cm–2, and FF = 55.6%). As a result, the PF1-TS4-60-based all-PSCs achieved a PCE of 9.31%, which is ∼50% higher than the PF1-TS4-based ones (6.17%). The results demonstrate a promising approach to develop high-performance nonconjugated terpolymer acceptors for efficient all-PSCs by means of ternary polymerization using two different A–D–A-structured fused-ring electron-deficient building blocks.

π-π conjugation promoted nanocatalysis for cancer therapy based on a covalent organic framework.

The production of reactive oxygen species (ROS) to elicit lethal cellular oxidative damage is an attractive pathway to kill cancer cells, but it is still hindered by the low ROS production efficiency of the current methods. Herein, we design a one-dimensional (1D) π-π conjugated ferriporphyrin covalent organic framework on carbon nanotubes (COF-CNT) for activating nanocatalytic and photodynamic cancer therapy. The COF-CNT can catalyze the generation of ROS and O2 in the tumor microenvironment (TME), and realize a self-oxygen-supplying PDT under near-infrared (NIR) light irradiation, simultaneously. With the full electron delocalization at the atomically dispersed active center, the catalytic activity of COF-CNT with extended π-conjugation is 6.8 times higher than that without the π-conjugated structure. The formation of the COF structure with π-π conjugation also changes the density of states (DOS) profile of its functional building block for improving PDT. Through one single treatment, it successfully achieves complete tumor regression of 4T1 breast carcinoma in mice with immunoregulation.

Developing strong NIR absorption materials through linear planar π-conjugated cyclopalladated complex dimers.

Near-infrared absorption metal complexes (NIRMCs) have been traditionally associated with the π-expanded macrocycle structure. However, macrocyclic ligands suitable for NIRMCs require a laborious synthetic route, and are a limited few. Herein, we report a kind of NIRMC based on linear large planar π-conjugated cyclopalladated dimers, which can be obtained by a facile base-induced dimerization of corresponding monomers. These dimers show an intense absorption in the NIR region with ε770 nm = 2.5 × 105 cm-1 M-1, and display a fluorescence emission peak at ca. 910 nm. Quinoid thiophene methine (QTM) and the cyclopalladated structure are speculated to be the key factors for their strong NIR absorption, which provides a different perspective of preparing NIR absorption metal complexes.

Utilizing spent Li-ion batteries to regulate the π-conjugated structure of g-C3N4: a win–win approach for waste recycling and highly active photocatalyst construction

This study utilizes spent LIBs to regulate the π-conjugated structure of g-C3N4, which realizes an all-win situation for waste recycling, highly active photocatalyst construction and environmental protection.

An extended carbonyl-rich conjugated polymer cathode for high-capacity lithium-ion batteries

A novel polymer with an extended π-conjugated structure (PPh-PTO) can show a delocalized electronic distribution and achieve a higher voltage, excellent cycle life, and good rate capabilities.

Efficient promotion and transfer of excited charge carriers in phosphorus doped and Ni complex modified g-C3N4

Solar hydrogen energy generation via photocatalysis can play a vital role in reducing global warming, environmental pollution, and the ever-increasing energy demand. Herein, phosphorus and Ni complex modified g-C3N4 were prepared by a hydrothermal method. The bonding of electron-rich phosphorous heteroatom to the g-C3N4 changed the morphology of the g-C3N4 from nanosheets into nano-rods and significantly altered the electronic structure, as evident by the shift in the conduction band edge and bandgap of g-C3N4. FTIR and XPS measurements revealedthat the triazine ring is oxygen functionalized and the P atom bonded to g-C3N4 via PN bond. Furthermore, EPR, UPS, and UV-DRS measurements revealed that the P and Ni complex reduced the localized π-conjugated structure defects of g-C3N4 and extended the light absorption into the near IR region. The Ni complex in the photocatalysts provided the additional charge transfer band of IMCT and OMCT. EDS color mapping revealed that the Ni complex is distributed uniformly on the P-g-C3N4 surface. These surface embedded Ni complex acts as an electron trap state, thereby suppressing the charge pair recombination rate which was confirmed by the PL and TRPL measurements. The synergetic effect of Ni complex and P resulted in 86 % tetracycline degradation in 20 min. and 3272 μmol/g of H2 production in 4 h. Compared to bulk g-C3N4, 818 times higher H2 production activity was achieved for the P and Ni complex modified g-C3N4.

Enhanced Two-Photon Absorption of Cross-Conjugated Chalcone Derivatives: Modulation of the Effective π-Conjugated Structure.

Three cross-conjugated chalcone derivatives T3CT, T3CP2, and T3CP3 were designed and synthesized to develop excellent organic nonlinear optical (NLO) materials. In a Z-scan experiment, all compounds show good NLO absorption characteristics in the visible to near-infrared region. The photophysical mechanism is confirmed to be two-photon absorption (TPA)-induced excited-state absorption (ESA). Intramolecular charge transfer (ICT) observed in transient absorption spectra (TAS) significantly affects molecular NLO properties. We define the π-conjugated system that dominates the electron transition process in the cross-conjugated structure as the effective π-conjugated structure. Electron transition analysis shows a sufficiently strong ICT can effectively expand the effective π-conjugated structure in these cross-conjugated structures. The TPA cross sections of these compounds at 650 and 750 nm are only in the range of 17-97 GM. However, we achieve a significant enhancement of the TPA cross section at 580 nm (1737-2027 GM) by extending the effective π-conjugated structure. Excited by 580 nm femtosecond laser pulses, all compounds exhibit excellent OL performance and the minimum OL threshold is 4.71 × 10-3 J/cm2. The results show that these cross-conjugated chalcone derivatives have promising applications in OL, and their NLO performance can be effectively improved by modulating the effective π-conjugated structure.

A novel long-wavelength off-on fluorescence probe for nitroreductase analysis and hypoxia imaging

Hypoxia is one of the most important features of various diseases including solid tumors. It is of significant clinical importance for hypoxia analysis in tumors, and the analysis of hypoxia can be moved away to the indirect detection of nitroreductase. Various fluorescence methods have been developed for the analysis of nitroreductase and tumor hypoxia due to their simplicity, non-invasiveness and excellent spatial-temporal resolution. Here, we synthesized a multifunctional fluorophore, which possesses larger π-conjugation structure, leading to the red-shift of absorption and fluorescence emission to long-wavelength region. This fluorophore (RCOH) can be further used to prepare the off-on hypoxia probe (RCO-NTR) by introducing the electron withdrawing group of nitrobenzyl, leading to the quenching of fluorescence emission through an electron transfer process. After reaction with NTR accompanied by NADH as an electron donor, the nitro group in the RCO-NTR probe can be reduced and then the RCOH fluorophore can be released through rearrangement and elimination, leading to the enhancement of fluorescence signal. Thus, the prepared RCO-NTR probe can be used for nitroreductase analysis, which can be further used for hypoxia imaging at both cellular and animal levels.

Covalent Graphene-MOF Hybrids for High-Performance Asymmetric Supercapacitors.

In this work, the covalent attachment of an amine functionalized metal-organic framework (UiO-66-NH2 = Zr6 O4 (OH)4 (bdc-NH2 )6 ; bdc-NH2 = 2-amino-1,4-benzenedicarboxylate) (UiO-Universitetet i Oslo) to the basal-plane of carboxylate functionalized graphene (graphene acid = GA) via amide bonds is reported. The resultant GA@UiO-66-NH2 hybrid displayed a large specific surface area, hierarchical pores and an interconnected conductive network. The electrochemical characterizations demonstrated that the hybrid GA@UiO-66-NH2 acts as an effective charge storing material with a capacitance of up to 651 F g-1 , significantly higher than traditional graphene-based materials. The results suggest that the amide linkage plays a key role in the formation of a π-conjugated structure, which facilitates charge transfer and consequently offers good capacitance and cycling stability. Furthermore, to realize the practical feasibility, an asymmetric supercapacitor using a GA@UiO-66-NH2 positive electrode with Ti3 C2 TX MXene as the opposing electrode has been constructed. The cell is able to deliver a power density of up to 16kW kg-1 and an energy density of up to 73Wh kg-1 , which are comparable to several commercial devices such as Pb-acid and Ni/MH batteries. Under an intermediate level of loading, the device retained 88% of its initial capacitance after 10 000 cycles.

Self-assembled supramolecular nanostructure photosensitizers for photocatalytic hydrogen evolution

Supramolecular self-assembly as a breakthrough methodology in the nanoscience and nanotechnology fields has attracted increasing attention. Highly ordered self-assembled supramolecular nanostructures aim to emulate natural light-harvesting and energy transfer and electron transfer processes, which have been an active and rapidly developing field for visible-light-driven photocatalytic applications. This Research Update aims to present the recent progress of the self-assembly of π-conjugated molecules, including perylene diimides (PDIs), porphyrin, and co-assembly of peptide–porphyrin as well as the shape-defined functional hierarchical structures. First, the basic principles of π-conjugated molecular structure design are described. The two nitrogen positions and the bay positions of PDIs can effectively regulate their electronic properties and geometric skeleton, and the functional groups and the good solvents of porphyrin effectively determine the choice of self-assembly methods. Then, the key morphology dependent optoelectronic properties and charge-transport and energy-transport functionalities are also discussed. These self-assembled supramolecular nanostructures’ inherent optoelectronic properties correlated with applications in photocatalytic water splitting into hydrogen evolution are overviewed. By now, the self-assembled In(III) meso-tetraphenylporphine (InTPP) porphyrin nanostructures exhibited the highest photocatalytic hydrogen generation activity among the reported supramolecular nanostructures owing to the central metal of porphyrin and small size of the InTPP nanostructure. Finally, perspectives on the crucial issues and potential future research directions are addressed. This Research Update will provide a new reference for building high performance, stable, and durable photosensitizers based on the supramolecular assembly.

Molecular design of dibenzo[g,p]chrysene-based hole-transporting materials for perovskite solar cells: A theoretical study

Designed with a steric twisted, π-conjugated dibenzochrysene (DBC) core and arylamine-based electron-donating side arms, four small molecules as hole-transporting materials (HTMs) are simulated with density functional theory and Marcus theory of electron transfer. Our results show that, adding the fluorene moiety in auxiliary side arms and extending the π-conjugated structure can make the highest occupied molecular orbital (HOMO) energy levels down-shifted. By tailoring of electron-donating side arms, the HOMO levels of designed HTMs range from −4.95 to −5.24 eV, which affords a chance for the interfacial energy regulation. Meanwhile, we also find that the suitable extension of π-conjugated side arms and the accessorial sulfur-sulfur interaction may be beneficial for promoting the intermolecular electronic coupling. Coupled with the lower reorganization energy, the DBC-4 (7.08 × 10−1 cm2 v−1 s−1) displays the largest hole mobility. In addition, the better solubility can be expected for the DBC-4 due to the larger solvation free energy, whereas its stability may be somewhat lower. Adding thiophene unit in side arms makes the absorption spectra obviously red-shift. Overall, this work provides some useful clues for designing of high-efficient HTMs, and the DBC-4 is proposed as potential HTM.