Organic photodetectors (OPDs) have emerged as promising alternatives to inorganic photodetectors because of their low-cost fabrication, lightweight, ease of processing, mechanical flexibility, and tailorable optical properties. Herein, a new donor polymer based on a naphtho[2,1-b:3,4-b’]dithiophene (NDT) backbone, which is a rigid, planar, symmetric, and electron-rich π-conjugated framework, was synthesized for green-selective OPDs. The polymer exhibited strong absorption at 535 nm and suitable optoelectronic properties for device fabrication. Bulk heterojunction OPDs were fabricated using PNDT and PCBM blend ratios of 1:1, 1:2, and 1:4, with different donor-to-acceptor weight ratios. Device performance strongly depended on the PNDT: PCBM blend ratio. Increasing the PCBM content enhanced photocurrent generation, whereas excessive PCBM also increased the reverse dark current. Consequently, the 1:1 blend exhibited the highest specific detectivity owing to its suppressed dark current with moderate photocurrent. These results highlight PNDT as a promising active material for high-performance green-selective organic photodetectors.
ZnSe/ZnTe Type-II hybrid interfaces were formed within honeycomb-patterned porous polymer films through a modified breath figure method under ambient conditions. The resulting hybrid films exhibited broadened visible-light absorption and markedly suppressed photoluminescence, indicating efficient interfacial charge separation. The hydrophobic porous framework further promoted the preferential localization of poorly water-soluble dye molecules, leading to enhanced visible-light photocatalytic degradation, particularly for alizarin. This simple fabrication strategy provides an effective platform for constructing immobilized hybrid semiconductor interfaces within porous polymer films. ZnSe/ZnTe Type-II hybrid interfaces were successfully immobilized within honeycomb-patterned porous polymer films by a modified breath figure method under ambient conditions. The hybrid-interface films exhibited broadened visible-light absorption and markedly suppressed photoluminescence, indicating enhanced interfacial charge separation. The hydrophobic porous framework further promoted preferential localization of poorly water-soluble dye molecules, resulting in significantly improved visible-light photocatalytic degradation, particularly toward alizarin.
Neutral organic radicals represent a highly promising class of materials for next-generation optoelectronic devices due to their unique open-shell electronic structures characterized by unpaired electrons. When incorporated into the backbone of conjugated polymers, these organic radicals can yield highly emissive materials suitable for organic light-emitting applications. To achieve practical utility, these polymers must carefully balance electronic delocalization with necessary steric shielding to protect the reactive radical centers. While such structural designs afford stability, realizing efficient radical-based emission in the near-infrared spectrum—particularly at wavelengths exceeding 750 nm—remains a formidable scientific challenge. Herein, we report a new series of highly stable donor–acceptor open-shell π-conjugated polymers based on a mesitylated tris(2,4,6-trichlorophenyl)methyl (TTM) radical core, giving tunable near-infrared doublet emission up to 883 nm. The polymers were prepared by Suzuki–Miyaura cross-coupling of the mesitylated TTM acceptor with fluorene, diphenylamine, and phenothiazine donor monomers, followed by deprotonation and oxidation to generate the corresponding polyradicals. Optical measurements showed that the donor unit effectively controlled the emission wavelength, whereas cyclic voltammetry indicated reversible redox behavior. Time-dependent ultraviolet–visible spectroscopy further confirmed the excellent solution stability over 37 d under ambient conditions. These results demonstrate that donor tuning in TTM-based polyradicals is an effective strategy for accessing stable NIR-emissive open-shell materials for next-generation organic luminescent materials. Donor-tunable NIR emission from TTM-based open-shell polymers
Wood-plastic composites (WPCs) are recognized as eco-friendly materials, yet their mechanical performance is often limited by the inherent incompatibility between hydrophilic wood flour and a hydrophobic polypropylene (PP) matrix. To address this challenge, resource-circulating WPCs were fabricated by compounding post-industrial recycled polypropylene (PIR PP) injection-molding waste with Larix kaempferi wood flour and maleic anhydride-grafted-polypropylene (MAPP) using twin-screw extrusion. The effects of varying MAPP content on chemical bonding, morphology, tensile properties, and thermal stability were systematically investigated. The composite containing an optimal 5 phr MAPP loading demonstrated the highest performance, achieving a tensile strength of 44.84 MPa and a tensile modulus of 1600.96 MPa, significantly surpassing the control composite without MAPP (29.27 MPa and 820.62 MPa, respectively). This optimal formulation also increased the maximum thermal degradation temperature (Tmax) by 24.68 ℃. In contrast, excess MAPP (7 and 9 phr) resulted in filler agglomeration and reduced properties due to compatibilizer self-aggregation. Overall, the 5 phr MAPP formulation provided the best balance of mechanical and thermal performance, establishing a robust strategy for upcycling industrial polymer waste into high-performance biomass composites.
Cured epoxy networks feature high modulus and thermal stability due to their intrinsically high crosslink density. However, this dense structure makes them brittle and prone to rapid crack initiation and propagation. Conventional toughening routes trade this brittleness for a loss of stiffness or of thermal resistance. Here, we report a hybrid toughening strategy. First, a homogeneous, molecularly hybrid prepolymer is synthesized. This prepolymer is then converted in situ into a heterogeneous interpenetrating polymer network (IPN) within a diglycidyl ether of bisphenol A (DGEBA)/4,4’-diaminodiphenylmethane (DDM) matrix. Octa(3-mercaptopropyl)-polyhedral oligomeric silsesquioxane (POSS-SH) was prepared by an acid-catalyzed sol-gel route in 87
