Cysteine (Cys) plays a critical role in both physiological and food domains, with abnormal levels being closely linked to various diseases. Therefore, the development of highly selective and sensitive detection methods is essential. In this study, a "On-off" fluorescent probe, TPA-DNBS, based on a triphenylamine (TPA) derivative, was designed. Compared to traditional probes, TPA-OH offers greater rigidity, stronger conjugation, and a larger Stokes shift, demonstrating superior signal-to-noise ratio and detection stability in complex biological and environmental samples. The probe exhibits specific response to Cys via a photo-induced electron transfer (PET) mechanism: in the presence of Cys, the DNBS quencher group is cleaved, leading to a significant increase in fluorescence. The probe shows excellent detection performance, with a linear range from 1 × 10⁻³ M to 1 × 10⁻⁹ M and a detection limit as low as 1.05 nM, along with good selectivity, interference resistance, stability, and reproducibility. In practical sample analysis, the recovery rates of spiked Cys in milk and mineral water were 99.7%-106.6% and 102.1%-103.3%, respectively, with relative standard deviations below 2.5%. These results indicate the broad applicability of the probe in complex samples.

A supramolecular fluorescent substance constructed by cucurbit [8]uril and triphenylamine derivate: AIE properties and application for the detection of 4-nitroaniline in aqueous system.

Electrochromic materials have recently aroused extreme attention due to their exceptional application potential in display screens, architectural glass, and coating stealth materials, etc. Developing electrochromic polymers synchronously sharing blue and second near-infrared (NIR-II) transmissive is urgently in demand but extremely scarce. Herein, three kinds of electrochromic polymers featuring redox electrochemical and electrochromic properties are obtained through electrochemical polymerization of three monomers, ProDOT-TPA, ProDOT-TPPA, and ProDOT-2TPA, which are constructed based on 3,4-ethylenedioxythiophene (ProDOT) and triphenylamine (TPA) derivatives. Electrochemical studies reveal that ProDOT-TPA exhibits low initial oxidation potential of 0.59 V, possessing significant advantages for obtaining high-quality polymers. The optimized polymers [P(ProDOT-TPA)] show significant properties in electrochromic devices with optical contrast of 14.38% at 400 nm and 49.55% at 1100 nm, along with coloration efficiency of 123 cm2 C-1 and response times of 0.5 s.

Ammonia borane is a promising hydrogen storage material due to its high hydrogen content, but its use as hydrogen carrier under thermal stimuli involves the production of several byproducts, such as borazine, reducing hydrogen purity and the overall efficiency. This work is focused on the use of high-boiling-point amines to modulate ammonia borane decomposition, aiming to enhance hydrogen release and suppress volatile NxBy species. Kissinger’s equation kinetics revealed that amines significantly influence the decomposition mechanism, and TGA-IR investigation showed a maximum of 2.4 wt.% of pure hydrogen release in the presence of triphenyl amine. Furthermore, the experimental data herein discussed, together with a computational study of activation energies, allowed us to derive a detailed mechanism that leads to a foundation for further advancement in the exploitation of ammonia borane as a hydrogen carrier, suggesting that the formation of linear species is anchored to amine over the release of borazine and production of poly borazine-like species.

Panchromatic dyes extending the absorption up to the near-infrared region stand out as excellent candidates for light harvesting and biological applications. One of the viable ways to construct panchromatic dyes involves the strategic selection of a molecular platform that can accommodate multiple chromophores absorbing at varied wavelength ranges. Even though azadipyrromethene (azaBODIPY) offers such a molecular skeleton, reports on broadband absorbing azaBODIPYs and related photoinduced interchromophore energy/electron transfer events intending to provide desirable functions such as electron migration and charge separation (CS) are still inadequate. In this context, multiheteroaromatic tethered azaBODIPY, (PTZ)2-AB-(TPA)2, containing phenothiazine (PTZ) and triphenylamine (TPA) integrated into azaBODIPY core has been synthesized and light-induced electron transfer events were explored. Parallely, control compounds involving azaBODIPYs with either TPA or PTZ moieties, (Ph)2-AB-(TPA)2 and (PTZ)2-AB-(Ph)2, and pristine Et-PTZ and TPA were synthesized, and the roles of the individual constituents in the photoinduced events are investigated. Optical absorption studies have revealed that the substitution of azaBODIPY skeleton with PTZ and TPA moieties at 1,7- and 3,5-positions enhanced the extended π-conjugation and resulted in broader absorption extending beyond 1000 nm. Electrochemical studies have displayed first oxidation from either TPA or PTZ, and first reduction from the azaBODIPY moieties indicating that TPA or PTZ would behave as electron donors and azaBODIPY as the electron acceptor, and computational studies have corroborated the results. Steady-state fluorescence studies in solvents of varied polarity, involving selective excitation of PTZ at 265 nm and TPA at 300 nm resulted in quenching of the PTZ or TPA emission indicating the occurrence of photoinduced electron transfer (PET) from 1PTZ* or 1TPA* to azaBODIPY. Time-correlated single photon counting studies confirmed the quenching of overall lifetimes of the azaBODIPYs indicating the presence of PET within these systems. Systematic femtosecond transient absorption studies revealed the optical signatures of TPA+• or PTZ+• displayed at 550 and 650 nm, respectively, authenticating the occurrence of PET from excited TPA or PTZ to azaBODIPY with a very short formation time of CS states (14, 61, and 7 ps for (PTZ)2-AB-(Ph)2, (Ph)2-AB-(TPA)2 and (PTZ)2-AB-(TPA)2, respectively), and a long charge recombination in the nanosecond time domain, and highlighted the versatility of azaBODIPY as an electron relay in light-induced events.

Organic small molecules have emerged as promising cathode candidates for aqueous zinc-ion batteries owing to their structural tunability and high redox activity. However, their development is hindered by inherently low operating voltages and limited specific capacities. Herein, a bipolar organic molecule is reported featuring intramolecular asymmetric charge distribution. By incorporating multiple strong electron-withdrawing nitro groups (-NO2) within a single molecular framework, the bandgap is substantially narrowed, leading to enhanced electrochemical activity and improved ion storage capability. Concurrently, the triphenylamine (TPA) moiety serves as an efficient redox-active center, significantly accelerating the redox reaction kinetics. This unique charge asymmetry design achieves an alternating storage mechanism for cations and anions by synergistically enhancing redox activity and kinetic performance. As a result, assembled batteries can deliver high performance (356 Wh kg-1 at 172.5 W kg-1, with cycle stability of 10 000 cycles at 5 A g-1). This study provides a novel design paradigm for high-performance cathode materials by regulating the asymmetry of intramolecular charge distribution.

Multifunctional nile red-triphenylamine AIEgen for optical waveguides, lipid droplet imaging, and photodynamic therapy.

A series of donor-π-acceptor dyes were designed based on the structure of the experimentally reported TPP dye, which incorporates Triphenylamine (TPA) as the donor, Pyrazine as the π-bridge, and a carboxylic acid group as the acceptor. To enhance the photovoltaic performance of dye-sensitized solar cells, five new dyes (TPP1-TPP5) were modelled by introducing different alterations to the π-conjugated bridge. Density functional theory (DFT) and time-dependent DFT (TDDFT) calculations were carried out to examine how the alteration in the π-spacer influences the optical, electronic, and photovoltaic performance. All dyes displayed negative Gibbs free energy values for electron injection into TiO2, confirming the thermodynamic favourability of the charge transfer process. Short-circuit current density (JSC) was found as the highest for TPP3 and TPP4, outperforming the other TPP dyes with 1.40mAcm-2 and 1.87mAcm-2. Furthermore, with the lowest dye regeneration of ΔGreg = 0.46eV and a comparable open circuit voltage (Voc) of 1.17eV, TPA4 demonstrated higher regeneration kinetics. Natural bond order analysis was conducted to assess the bond strength and examine the molecular orbitals associated with the donor, π-spacer and acceptor unit. All the modelled dyes found strong non-linear optical characteristics having the linear polarizability (α) amplitudes greater than the first-order total polarizability (βtotal) relative to the experimental dye. Light harvesting efficiency of the modelled dye TPP4 was found the maximum (89%) among the studied dyes. These findings show that π-spacer alteration is an effective strategy for improving overall dye performance in DSSCs. Optimization of all species by using Gaussian16 with functional B3LYP and basis set 6-311G (d,p). NBO analysis was performed to explore the interactions between the filled orbitals of one part and the vacant orbitals of another part. TDDFT studies were performed using ORCA4.2 with Zeroth-Order Regular Approximation for accounting relativistic effects to calculate excitation energies.

Herein, we report the design and green synthesis of stereodefined tetrasubstituted alkenes (TPA-V-S, TPA-V-SO, and TPA-V-SO2) bearing a triphenyl amine (TPA) and a sulfenyl or sulfoxide, or sulfone functional group situated in the anti-orientation and two phenyl rings anti to each other. Notably, TPA-V-S exhibited reversible vis-to-NIR electrochromism with a high optical contrast of 70.6%, suitable for transparent-to-black (TTB) smart window applications. Additionally, the electrochromic smart window effectively decreased the solar heat gain by 82% in the black state.

The rational design of metal-free organic sensitizers is critical for developing cost-effective, high-efficiency dye-sensitized solar cells (DSSCs). This study uses density functional theory (DFT) to explore how modifying the triphenylamine (TPA) donor with pyridine rings or amino groups at ortho-, meta-, and para-positions affects the optoelectronic properties of D-π-A sensitizers. Our calculations show that para-position amino substitution (dye N3) yields the most red-shifted absorption ( =523, 50 nm beyond reference dyes), the highest theoretical open-circuit voltage (Voc = 1.77 eV, 0.3 eV higher than others), and enhanced charge transfer efficiency. These findings highlight para-position amines as a promising strategy for optimizing DSSC performance and identify N3 as a prime candidate for synthesis and experimental validation. Ground-state geometries, vibrational frequencies, and frontier molecular orbitals were calculated using the M06 functional with the 6-31G(d) basis set, chosen for its accuracy in organic systems. UV-Vis absorption and excited-state properties were predicted via time-dependent DFT (TD-DFT) with the M06-2X functional, optimized for excited-state accuracy, and the 6-31G(d) basis set. Solvation effects in acetonitrile were modeled using the IEF-PCM polarizable continuum model. Calculations were performed with Gaussian 16.

The development of advanced sensing systems for the selective detection of metal ions, such as copper (Cu 2+ ), is a pressing challenge in modern analytical and environmental chemistry due to their dual role as essential elements in biological systems and potential toxins at elevated concentrations. Herein, a novel fluorescent organic cage based on a triphenylamine (TPA) chromophore is introduced, designed specifically for the detection of Cu 2+ ions in water. The design concept involves the incorporation of two dynamic covalent bonds: acylhydrazone and disulfide, within a single cage structure, imparting adaptability and exceptional sensing performance. This cage demonstrates a distinct “turn‐off” fluorescence response, with a pronounced signal decrease upon Cu 2+ binding, offering reliable and accurate quantitative detection. Additionally, the system provides qualitative, visible colorimetric responsivity, enabling straightforward, visual detection without the need for advanced instrumentation. Its high selectivity toward Cu 2+ , combined with a low detection limit of 4.75 μM, ensures precise analysis even in the presence of competing metal ions. Practical applicability is demonstrated through the successful detection of Cu 2+ in real water samples, highlighting the system's potential for environmental monitoring and field application.

Donor-Acceptor (D-A) systems in which a triphenylamine has tethered at meso phenyl position of corrole (1-TPA-Cor) corrole monomer, (2-TPA-Cor) corrole dimer, and (3-TPA-Cor) corrole trimer have been designed and synthesized. All three D-A systems have been characterized by various spectroscopic techniques that include 1H NMR, 13C NMR, HR -MS, absorption, and emission (both steady-state and lifetime) spectroscopies as well as electrochemical methods. Optical and theoretical studies suggest that there will be π-π interactions between donor triphenylamine (TPA) and acceptor corrole (Cor) units and as a result both Soret and Q-bands are red-shifted with broadening of Soret band. Selective excitation of TPA in these D-A systems at 300nm resulted in the quenching of TPA emission suggested the photo-induced electron transfer (PET) from 1TPA* to corrole. In contrast, excited at 405nm also resulted in quenching of emission of Cor. As the number of corrole units and polarity of the solvent increased the quenching is more and suggested that PET reactions in these D-A systems. Time-resolved fluorescence studies shown the presence of PET within these systems and revealed an ultra-fast electron rate of ∼108 to 1010s-1, follows the order 3-TPA-Cor>2-TPA-Cor>1-TPA-Cor and are polarity of solvent dependent.

Abstract Long‐lived luminescent materials have garnered considerable attention due to their fascinating self‐sustained afterglow emission and promising applications. However, most afterglow materials remain constrained to high‐energy excitation, inducing accelerated photodegradation and posing biosafety risks through mutagenic effects. Herein, the study presents a molecular engineering paradigm in low‐energy excitation to realize long‐lived visible‐light‐excitable phosphorescence (VEP) via controllably modulating charge transfer (CT) processes in donor‐acceptor (D‐A) designed fluorophores. By anchoring electron‐donating triphenylamine (TPA) to a π‐accepting terpyridine (Tpy) unit, the D‐A engineered fluorophores serve as versatile platforms for introducing dynamic Zn(II)‐Tpy coordination and sequential protonation to largely enhance CT for bathochromic absorption shift, thereby enabling tunable and multicolor VEP. Furthermore, the photo‐oxidation process induces structural evolutions of fluorophores to modulate intramolecular CT (ICT), resulting in ultralong VEP lasting more than 3 s (artificial sunlight excitation) and 1 s (low‐power LED) under ambient conditions. Encouraged by the tunable properties of these versatile VEP materials, time‐gated anti‐counterfeiting and multi‐level encryption are demonstrated with a high security level. This work establishes an effective toolbox for designing and fabricating VEP materials through precise CT engineering, advancing their adaptability for next‐generation photonic technologies.

Generating a vast chemical space for high polar surface area triphenylamine polymers by machine learning-DFT calculations assisted reverse engineering for photovoltaics.

Photodynamic therapy (PDT) has emerged as a promising strategy for pancreatic cancer treatment, yet its efficacy is hindered by the limited reactive oxygen species (ROS) generation efficiency of conventional photosensitizers (PSs). Herein, we adopted a PS with a donor-acceptor structure as the researched object, which chose triphenylamine (TPA) and benzothiadiazole as an electronic donor and an acceptor. Another electronic donor of anisole and an electronic acceptor of nitrophenyl were introduced to the researched object to obtain two PSs of BLY-719 and BLY-720, which aimed to enhance PDT performance through rational modulation of electronic donor/acceptor pairs. Systematic investigations revealed that the enhancement of acceptor strength significantly reduced energy splitting between the singlet and triplet states, thereby boosting ROS generation, including singlet oxygen and hydroxyl radical, but the fluorescent intensity of the emitter showed an obvious reduction. However, the introduction of the electronic donor anisole not only achieved better fluorescent strength but also maintained satisfactory ROS efficiency. The investigation of therapeutic effect using pancreatic cancer cells of SW1990 as the object demonstrated that the donor-modified PS-based nanoparticles (NPs) achieved the most cell mortality at a 100 μg/mL dosage after undergoing white light irradiation. This work provides a molecular design paradigm for developing highly efficient therapeutic agents against intractable cancers.

Spectroscopic and computational analyses were employed to investigate a series of donor-acceptor dyes connected by a fused dithiophene (dctp) 4,4-dihexyl-4H-cyclopenta[2,1-b:3,4-b']. The donor units employed were triphenylamine (TPA) and carbazole (Cbz), while the acceptor units included Indane-based 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (InOCN) and 1H-indene-1,3(2H)-dione (IndO). A charge-transfer (CT) transition was evident in the electronic absorption spectra between 17,300 and 15,000 cm-1. Each dye exhibited a singlet state of CT emission across all of the dyes. Emission spectra were observed from 14,700 to 13,100 cm-1. Resonance Raman spectroscopy (RRS) was utilized to experimentally validate the time-dependent density functional (TD-DFT) findings. Furthermore, the results reveal that CT in 2-((6-(9-ethylcarbazol-3-yl)-4,4-dihexylcyclopenta[2,1-b:3,4-b']dithiophen-2-yl)methylene)indene-1,3-dione (PX134) and 2-(2-((6-(9-ethylcarbazol-3-yl)-4,4-dihexylcyclopenta[2,1-b:3,4-b']dithiophen-2-yl)methylene)-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (PX135) occurs from the donor-π system to the acceptor, whereas in ((6-(4-(diphenylamino)phenyl)-4,4-dihexylcyclopenta[2,1-b:3,4-b']dithiophen-2-yl)methylene)indene-1,3-dione (PX137) and 2-(2-((6-(4-(diphenylamino)phenyl)-4,4-dihexylcyclopenta[2,1-b:3,4-b']dithiophen-2-yl)methylene)-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (PX138), it proceeds from the donor to the π-acceptor units. These compounds exhibited distinct solvatochromic behavior in their absorption and emission spectra. These variations are analyzed using Lippert-Mataga (LM), McRae (MR), and Weller plots, which indicate changes in dipole moments between the ground and excited states. The linear slopes derived from the LM, MR, and Weller plots suggest a well-defined CT process with minimal specific solvent interactions. Density functional theory (DFT) modeling also suggests a significant level of planarity across all four dyes, and the experimental Raman spectra closely match the calculated Raman spectra. Compared to IndO groups, malononitrile units induce a greater CT character in the spectral emission behavior of each molecule. Variable temperature (VT) study reveals a blue shift with the increase in temperature across all of the dyes, indicating no evidence of aggregation.

Three new fluorene-9-ylidene (F-9-Y)-based donor-acceptor dyes with varying donor strength and linker length were synthesized and studied to understand their photophysical properties for potential optoelectronic applications. The dyes incorporate dimethylaniline (DMA), triphenylamine (TPA), and bis(diethylaniline) (B-DEA) as donor groups, with B-DEA having an extended allyl linker. Spectroscopic techniques (UV-vis, emission, Raman) and DFT calculations (B3LYP/6-31G(d)) were used to probe their electronic structure and charge transfer behavior. B-DEA exhibited broader absorption (360-600 nm) due to an additional intramolecular charge transfer transition (CT2), although CT2 showed a lower charge transfer character than CT1 in DMA and TPA. Stokes shifts, dipole moment changes, and excited-state geometries confirmed this. The extent of the conjugation and orbital alignment had a more pronounced effect on the charge transfer efficiency than the donor. Due to the nonradiative decay pathways, low quantum yield and short lifetimes were recorded for all dyes. These findings highlight how structural variations influence charge transfer properties and suggest promising applications in organic solar cells.

Dual-state luminescent materials, which emit strongly in both dispersed and aggregate states, are highly desirable for advanced optoelectronic and sensing applications. In this study, we rationally designed a series of benzimidazole-based donor-π-acceptor (D-π-A) compounds using triphenylamine (TPA) as the donor and benzimidazole as the acceptor, functionalized with flexible alkyl chains to modulate intermolecular packing. Benefitting from their rigid planar molecular conformation, all four compounds exhibit intense blue fluorescence in both solution and the PMMA-doped state. Among them, the highest luminescence efficiencies of the molecule C0 in the DCM- and PMMA-doped films reach 78.72% and 65.28%, respectively. Notably, their PMMA-doped films also exhibit obvious yellowish-green afterglows after5s continuous UV irradiation. In the solid state, the chain-free molecule C0 forms a staggered stacking with intermolecular hydrogen bonds, resulting in a bright excimer emission. As the alkyl chain length increases, the added steric bulk gradually suppresses the intermolecular interactions, inducing a significant transition from excimer emission to blue-shifted monomer emission. Furthermore, the nitrogen atom of benzimidazole endows these luminophores with pronounced acid-responsive fluorescence behavior. By exploiting the distinct luminescent contrast between the excimer and monomer emissions of C0, we developed a temperature-responsive fluorescence system through embedding C0 into a phase-change matrix, which enables a reversible thermochromic fluorescence switching. This work provides a valuable strategy for designing dual-state emission and stimuli-responsive benzimidazole-based materials with potential applications in optical sensing and display technologies.

We report the excited-state dynamics of π-orthogonal donor–acceptor dyads based on perylene (Pe) and phenothiazine (PTZ), in which triphenylamine (TPA) units and a phenyl spacer were introduced to modulate donor strength and spatial separation. Among the series, Pe–PTZ(TPA)2 exhibits a distinct thermal equilibrium between the locally excited (LE) state of the PTZ moiety and the photoinduced charge-transfer (CT) state. Femtosecond to microsecond transient absorption spectroscopy reveals that this equilibrium is facilitated not simply by enhanced donor ability, but presumably by excited-state planarization of the PTZ moiety, which lowers the energy of the LE state of the PTZ moiety. In contrast, Pe-Ph–PTZ(TPA)2, in which the donor–acceptor distance is increased by a phenyl spacer, does not show clear equilibrium behavior. These results underscore the crucial role of excited-state structural relaxation in tuning photoinduced charge separation, and demonstrate that precise electronic and geometric design can enable controllable excited-state behavior in orthogonal molecular systems.

Advancements and future perspectives of triphenylamine-based fluorescent probes in biomedical applications.