Search Results (67)

We report the synthesis and characterization of the two enantiomeric forms of a thienyl-substituted diketopyrrolopyrrole (DPP) derivative bearing chiral alkyl chains. Thin films were prepared either by spin-coating and drop-casting and analyzed by UV–Visible absorption, electronic circular dichroism (ECD), and circularly polarized (CP) luminescence (CPL). ECD spectra confirmed the opposite chirality of the (R) and (S) isomers, while CPL measurements of the S enantiomer demonstrated solid-state chiroptical activity. Preliminary device tests showed promising optoelectronic behavior, highlighting these chiral DPP materials as potential candidates for CP organic light-emitting diodes (CP-OLEDs) applications, combining strong chiroptical response with good film quality. Full article

This study investigates thienyl-substituted diketopyrrolopyrrole (DPP) derivatives with tailored alkyl chain modifications on the DPP core to tune molecular packing, solubility, and optoelectronic properties critical for device applications. A key advancement is the use of microwave-assisted synthesis, which dramatically reduces reaction times (40 min vs. 12 h), improves yields (up to 80% for long chains), and lowers energy consumption, supporting green chemistry principles. The combined strategy of molecular engineering and efficient synthesis enables sustainable production of high-performance DPP materials. Full article

Mimicking artificial photosynthesis utilizing solar energy for the production of high-value chemicals is a sustainable strategy to tackle the fossil fuel-based energy crisis and mitigate the greenhouse effect. In this study, we developed a two-dimensional (2D) graphene oxide (GO)–diketopyrrolopyrrole (DPP) film photocatalyst. GO nanosheets facilitate the uniform dispersion of DPP nanoparticles (~5 nm) while simultaneously constructing an efficient charge transport network to mitigate carrier recombination. Under visible-light irradiation in an aqueous solution without sacrificial agents, the optimized GO–DPP50 film catalyst exhibited exceptional performance, achieving a CO production rate of 32.62 μmol·g⁻¹·h⁻¹ with nearly 100% selectivity. This represents 2.77-fold and 3.28-fold enhancements over pristine GO (8.65 μmol·g⁻¹·h⁻¹) and bare DPP (7.62 μmol·g⁻¹·h⁻¹), respectively. Mechanistic analysis reveals a synergistic mechanism. The 2D GO framework not only serves as a high-surface-area substrate for DPP anchoring, but also substantially suppresses charge recombination through rapid electron transport channels. Concurrently, the uniformly distributed DPP nanoparticles improve visible-light absorption efficiency and facilitate effective photogenerated carrier excitation. This work establishes a novel paradigm for the synergistic integration of 2D nanomaterials with organic semiconductors, providing critical design principles for developing high-performance film-based photocatalysts and selectivity control in CO₂ reduction applications. Full article

The diketopyrrolopyrrole (DPP) core is widely recognized for its applications in organic electronics and photonics due to its exceptional electronic and optical properties. Recently, DPP-based materials have shown remarkable π–π stacking interactions and tunable self-assembly, making them promising candidates for gel formation. However, the development of DPP-based gels remains in its infancy, primarily hindered by challenges such as limited gelation efficiency, poor mechanical robustness, and sensitivity to environmental conditions. Overcoming these issues is crucial for unlocking their full potential in functional soft materials. This review compiles and analyzes existing studies on DPP-containing gel systems, highlighting their structural versatility, self-assembly mechanisms, and advantages over conventional gelators. By examining these works, we identify key strategies for DPP gel formation, evaluate their physicochemical performance, and discuss innovative approaches to address current limitations. Finally, we propose future research directions to advance the field and establish DPP-based gels as a robust platform for next-generation soft materials. Full article

The market demand for black polyimide (BPI) has grown hugely in the field of flexible copper-clad laminates (FCCLs) as a replacement for transparent yellow polyimide. The 3,6-bis(thiophen-2-yl)diketopyrrolopyrroles (TDPP) derivative is recognized for its high molar extinction coefficient. In this research, we have synthesized a diamine monomer named 3,6-bis[5-(4-amino-3-fluorophenyl)thiophen-2-yl]-2,5-bis(2-ethylhexyl)pyrrolo[4,3-c]pyrrole-1,4-dione (DPPTENFPDA), featuring a TDPP unit attached by fluorinated benzene rings. The subsequent reaction of DPPTENFPDA with pyromellitic dianhydride (PMDA) yielded an inherent BPI (DPPTENFPPI). By introducing chromophores derived from TDPP, the light absorption spectrum of DPPTENFPPI was broadened and red-shifted, thereby achieving full absorption within the visible spectrum and producing a highly black color that has a cut-off wavelength (λ_cut) of 717 nm and a CIE-Lab coordinate L* of 0.86. Additionally, DPPTENFPPI exhibited a low coefficient of thermal expansion (CTE) and remarkable thermal and electrical performance. Density functional theory calculations were conducted to explore the electronic nature of DPPTENFPPI. The outcomes revealed that the excellent light absorption of DPPTENFPPI predominantly originates from the transition from HOMO to LUMO + 1 within the chromophore moiety. The FCCL made from DPPTENFPPI films has high solder heat resistance and peel strength. This research contributes valuable insights into the structure and design of high-performance intrinsically black PIs for microelectronics applications. Full article

Electropolymerization is a convenient way to obtain conducting polymers (CPs) directly adhered to an electrode surface. CPs are well-known for their various application fields in photovoltaic cells, chemical sensors, and electronics. By implementing chirality into a CP, the application possibilities will spread further onto chiral sensors or optoelectronics. In this work, we introduce a new inherently chiral polymer based on a macrocyclic 3,4-ethylenedioxythiophene-diketopyrrolopyrrole-3,4-ethylenedioxythiophene triad (EDOT-DPP-EDOT) fused by 1,4-phenylene groups, which was prepared via oxidative electropolymerization directly on the electrode surface. The investigation of the chiroptical properties was performed by circular dichroism spectroscopy in the solid state. The enantiomeric pure polymer films obtained showed dissymmetry factors of up to −2.71 × 10⁻⁴, whereby linear dichroism contributions can be widely excluded. Full article

Carbazole-based molecules play a significant role in dye-sensitized solar cells (DSSCs) due to their advantageous properties. Carbazole derivatives are known for their thermal stability, high hole-transport capability, electron-rich (p-type) characteristics, elevated photoconductivity, excellent chemical stability, and commercial availability. This review focuses on DSSCs, including their structures, working principles, device characterization, and the photovoltaic performance of carbazole-based derivatives. Specifically, it covers compounds such as 2,7-carbazole and indolo[3,2-b]carbazole, which are combined with various acceptors like benzothiadiazole, thiazolothiazole, diketopyrrolopyrrole, and quinoxaline, as reported over the past decade. The review will also outline the relationship between molecular structure and power-conversion efficiencies. Its goal is to summarize recent research and advancements in carbazole-based dyes featuring a D-π-A architecture for DSSCs. Additionally, this review addresses the evolution of carbazole-based hole-transport materials (HTMs), which present a promising alternative to the costly spiro-OMeTAD. We explore the development of novel HTMs that leverage the unique properties of carbazole derivatives to enhance charge transport, stability, and overall device performance. By examining recent innovations and emerging trends in carbazole-based HTMs, we provide insights into their potential to reduce costs and improve the efficiency of DSSCs. Full article

In recent years, the charge carrier mobility study of organic semiconductors has seen significant progress and surpassed that of amorphous silicon thanks to the development of various molecular engineering, solution processing, and external alignment methods. These advances have allowed the implementation of organic semiconductors for fabricating high-performance organic electronic devices. In particular, diketopyrrolopyrrole-based small-molecular and polymeric organic semiconductors have garnered considerable research interest due to their ambipolar charge-carrier properties. In this article, we focus on conducting a comprehensive review of previous studies that are dedicated to the external alignment, thermal annealing, and molecular engineering of diketopyrrolopyrrole molecular structures and side-chain structures in order to achieve oriented crystal orientation, optimized thin-film morphology, and enhanced charge carrier transport. By discussing these benchmark studies, this work aims to provide general insights into optimizing other high-mobility, solution-processed organic semiconductors and sheds lights on realizing the acceleration of organic electronic device applications. Full article

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. Full article

The design of novel acceptor molecular structures based on classical building blocks is regarded as one of the efficient ways to explore the application of organic conjugated materials in conductivity and electronics. Here, a novel acceptor moiety, thiophene-vinyl-diketopyrrolopyrrole (TVDPP), was envisioned and prepared with a longer conjugation length and a more rigid structure than thiophene-diketopyrrolopyrrole (TDPP). The brominated TVDPP can be sequentially bonded to trimethyltin-containing benzo[c][1,2,5]thiadiazole units via Suzuki polycondensation to efficiently prepare the polymer PTVDPP-BSz, which features high molecular weight and excellent thermal stability. The polymerization process takes only 24 h and eliminates the need for chlorinated organic solvents or toxic tin-based reagents. Density functional theory (DFT) simulations and film morphology analyses verify the planarity and high crystallinity of the material, respectively, which facilitates the achievement of high carrier mobility. Conductivity measurements of the polymeric material in the organic transistor device show a hole mobility of 0.34 cm² V⁻¹ s⁻¹, which illustrates its potential for functionalized semiconductor applications. Full article

Oligomers and polymers consisting of multiple thiophenes are widely used in organic electronics such as organic transistors and sensors because of their strong electron-donating ability. In this study, a solution to the problem of the poor solubility of polythiophene systems was developed. A novel π-conjugated polymer material, PDPP-5Th, was synthesized by adding the electron acceptor unit, DPP, to the polythiophene system with a long alkyl side chain, which facilitated the solution processing of the material for the preparation of devices. Meanwhile, the presence of the multicarbonyl groups within the DPP molecule facilitated donor–acceptor interactions in the internal chain, which further improved the hole-transport properties of the polythiophene-based material. The weak forces present within the molecules that promoted structural coplanarity were analyzed using theoretical simulations. Furthermore, the grazing incidence wide-angle X-ray scanning (GIWAXS) results indicated that PDPP-5Th features high crystallinity, which is favorable for efficient carrier migration within and between polymer chains. The material showed hole transport properties as high as 0.44 cm² V⁻¹ s⁻¹ in conductivity testing. Our investigations demonstrate the great potential of this polymer material in the field of optoelectronics. Full article

In this research, two polymers of P1 and P2 based on monomers consisting of thiophene, 3,4-Ethylenedioxythiophene (EDOT) and diketopyrrolopyrrole (DPP) are designed and obtained via Stille coupling polycondensation. The material shows excellent coplanarity and structural regularity due to the fine planarity of DPP itself and the weak non-covalent bonding interactions existing between the three units. Two different lengths of non-conjugated side chains are introduced and this has an effect on the intermolecular chain stacking, causing the film absorption to display different characteristic properties. On the other hand, the difference in the side chains does not have a significant effect on the thermal stability and the energy levels of the frontier orbitals of the materials, which is related to the fact that the materials both feature extremely high conjugation lengths and specific molecular compositions. Microscopic investigations targeting the side chains provide a contribution to the further design of organic semiconductor materials that meet device requirements. Tests based on organic transistors show a slight difference in conductivity between the two polymers, with P2 having better hole mobility than P1. This study highlights the importance of the impact of side chains on device performance, especially in the field of organic electronics. Full article

Polythiophene, as a class of potential electron donor units, is widely used in organic electronics such as transistors. In this work, a novel polymeric material, PDPPTT-FT, was prepared by incorporating the electron acceptor unit into the polythiophene system. The incorporation of the DPP molecule assists in improving the solubility of the material and provides a convenient method for the preparation of field effect transistors via subsequent solution processing. The introduction of fluorine atoms forms a good intramolecular conformational lock, and theoretical calculations show that the structure displays excellent co-planarity and regularity. Grazing incidence wide-angle X-ray (GIWAXS) results indicate that the PDPPTT-FT is highly crystalline, which facilitates carrier migration within and between polymer chains. The hole mobility of this π-conjugated material is as high as 0.30 cm² V⁻¹ s⁻¹ in organic transistor measurements, demonstrating the great potential of this polymer material in the field of optoelectronics. Full article

Organic dye semiconductors have received increasing attention as the next generation of semiconductors, and one of their potential applications is as a core component of organic transistors. In this study, two novel diketopyrrolopyrrole (DPP) dye core-based materials were designed and separately prepared using Stille coupling reactions under different palladium catalyst conditions. The molecular weights and elemental compositions were tested to demonstrate that both catalysts could be used to successfully prepare materials of this structure, with the main differences being the weight-average molecular weight and the dispersion index. PDPP-2Py-2Tz I with a longer conjugation length exhibited better thermodynamic stability than the counterpart polymer PDPP-2Py-2Tz II. The intrinsic optical properties of the polymers were relatively similar, while the electrochemical tests showed small differences in their energy levels. The polymers obtained with different catalysts displayed similar and moderate electron mobility in transistor devices, while PDPP-2Py-2Tz I possessed a higher switching ratio. Our study provides a comparison of such dye materials under different catalytic conditions and also demonstrates the great potential of dye materials for optoelectronic applications. Full article

In this communication, we report a novel acceptor structural unit, TVDPP, that can be distinguished from classical materials based on TDPP structures. By designing a synthetic route via retrosynthetic analysis, we successfully prepared this monomer and further prepared polymer P2TVDPP with high yield using a Stille-coupling polymerization reaction. The polymer showed several expected properties, such as high molecular weight, thermal stability, full planarity, small π−π stacking distance, smooth interface, and so on. The absorption spectra and energy levels of the polymer were characterized via photochemical and electrochemical analysis. The organic field-effect transistor (OFET), which is based on P2TVDPP, exhibited excellent carrier mobility and an on/off current ratio of 0.41 cm² V⁻¹ s⁻¹ and ~10⁷, respectively, which is an important step in expanding the significance of DPP-based materials in the field of optoelectronic devices and organic electronics. Full article