This study synthesized quantum dots (QDs) via a hydrothermal method at 165 °C using citric acid and cysteine hydrochloride as precursors. A simple, rapid, and highly sensitive quantitative detection method for Co2+ was established and applied to the analysis and monitoring of Co2+ in water and soil. The research found that Co2+ interacts with functional groups on the QDs (such as C-S, N-H, and C-O) through coordination, electrostatic, and Van der Waals forces, forming a stable, non-fluorescent ground-state complex. This leads to a significant quenching of the QDs’ fluorescence intensity at an excitation wavelength of 350 nm. After optimizing the detection conditions, the best performance was achieved at 25 °C, pH 9, with a mixing time of 5 min. The method demonstrated a good linear relationship within the range of 10–150 µM, with a linear regression equation of Y = -0.0053X + 0.95923 (R2 = 0.9894). The limit of detection (LOD) was calculated as 7.76 µM (based on 3σ/k). The quenching mechanism is attributed to the formation of a non-fluorescent ground-state complex between Co2+ and surface functional groups of the QDs, leading to static quenching via efficient electron/energy transfer. The inherent differences in binding constants with ligand groups and electron affinities among different metal ions—embodying the principle that “structure determines function”—enable effective discrimination between target Co2+ and potential interfering ions in complex aqueous matrices. Excellent recovery rates and precision obtained in real water and soil samples validated the reliability of the analytical signal.

In this study, hectorite intercalated with octadecyl trimethylammonium ions was synthesized via one-pot synthesis, and the octadecyl trimethylammonium-modified hectorite was used as an adsorbent to remove phenol from an aqueous solution. The pH and content of the adsorbent were studied to determine the optimized conditions for the adsorption of phenol. The phenol removal rate attained for 50 mL of 100 mg/L initial phenol solution at pH 12 was about 92.3% when 0.5 g of adsorbent was used. As for the adsorption isotherm, the Langmuir and Freundlich models were appropriate. The adsorption kinetics were in accordance with the pseudo-second-order model, and the activation energy (Ea) was about 11.15 kJ/mol. The modified hectorite could be recycled and reused, maintaining a high adsorption amount after five cycles.

Effect of zinc oxide-modified magnesium oxide (ZnO/MgO) and its preparation methods (two-or single-step calcination using zinc acetylacetonate or zinc acetate, respectively) on the thermal conductivity and thermal stability of PE was investigated. SEM, XRD, and XPS studies confirmed effec-tive deposition of ZnO on MgO surface, uniform particle distribution, preservation of MgO crystalline structure, and formation of a stable coating. The synergistic effect of both oxides significantly improved both the thermal conductivity and thermal stability of PE, with better results obtained using ZnO-mod-ified MgO manufactured in the two-step process. The highest thermal conductivity and thermal stabil-ity were observed for MgO containing 2 wt% ZnO. At higher ZnO content, agglomerates were formed, which resulted in deterioration of thermal properties.

A series of Mg-Al LDH-based photocatalysts were synthesized via a one-pot steam-assisted method, including pure Mg-Al LDH (MA), Zn-In ion-exchange-modified Mg-Al LDH (MAZ), BiOCl-loaded pristine Mg-Al LDH (MAB), and Zn-In-modified Mg-Al LDH co-loaded with TiO2 and BiOCl (MA/Zn-In/TiO2/BiOCl, MAZB). The one-pot synthesis facilitated the in situ intercalation and uniform loading of BiOCl/TiO2/Zn-In, while Zn2+/In3+ modified the MA layers via ion exchange, leading to an expansion of the interlayer spacing. The innovation of this work is reflected in two aspects: first, all raw materials are added via a one-pot strategy to achieve in situ preparation of modified hydrotalcite; second, this synthetic route features simple post-treatment without complicated washing, pressure filtration, and other tedious operations. The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and N2 adsorption-desorption isotherms. The bismuth chloride oxide/TiO2/LDHs exhibited a layered structure, with the active components uniformly distributed between the layers and on the MA surface. Under simulated sunlight irradiation, MAZB achieved 97.5% degradation of 20 mg/L MB within 120 min, with an apparent rate constant of 0.0297 min-1, which is 7.2 times, 2.4 times, and 2.9 times that of MA, MAZ, and MAB, respectively. The degradation rate of MAZB still remained at 89.5% after five cycles, demonstrating excellent stability and reusability. Compared with traditional hydrothermal methods, this steam-assisted system features mild reaction conditions (180 degrees C, atmospheric pressure), sodium-free raw materials, no washing requirement, and zero waste discharge, showing prominent green advantages.

Conjugated polymers are promising platforms for integrated optoelectronics, yet in most reported high mobility diketopyrrolopyrrole (DPP)-based semiconductors, strong intermolecular aggregation and narrow bandgaps suppress luminescence, limiting their applicability in multifunctional devices. The concurrent realization of efficient charge transport and strong thin film emission therefore remains a fundamental challenge. Here, we report two novel DPP-derived polymers, PTFBVDPP-V and PTFBVDPP-TVT, synthesized via Stille coupling through precise donor-acceptor (D-A) engineering. Both polymers possess highly coplanar backbones, forming continuous fiber networks and ordered crystalline films with close intermolecular pi-pi stacking. Polymer PTFBVDPP-V functions as a unipolar n-type semiconductor with an electron mobility (mu e) of 2.61 cm2 & centerdot;V-1 & centerdot;s-1 but negligible emission. In contrast, precise D-A modulation in PTFBVDPP-TVT enables balanced ambipolar transport with a hole mobility of 1.52 cm2 & centerdot;V-1 & centerdot;s-1 and an electron mobility of 1.15 cm2 & centerdot;V-1 & centerdot;s-1, while retaining a thin-film photoluminescence quantum yield (Phi) of 6.5%. This combination delivers a maximum Phi & centerdot;mu e exceeding 10-2 cm2 & centerdot;V-1 & centerdot;s-1, establishing a record performance among high-mobility ambipolar emissive polymer semiconductors and breaking the long-standing trade-off between charge transport and luminescence in conventional high-mobility DPP-based systems.

A series of nacre-inspired reduced graphene oxide/chitosan-Palladium (rGO/CS-Pd) composite papers with "brick-and-mortar" structure were prepared by a vacuum-assisted filtration induced self-assembly process, incorporating CS chains as "mortar" and rGO sheets as nano "bricks". Different types of defects of the starting rGO and prepared rGO/CS-Pd composite papers have been detected based on positron annihilation lifetime spectroscopy (PALS) measurements combining with other methods. Positron trapping annihilation in vacancylike defects of rGO, such as intrinsic Stone-Wales (S-W) defects of the graphene lattice, intrinsic C-vacancy defects of the graphene lattice, external introduced vacancy-like defects in the interfaces of the composites, are assigned to the intermediate lifetime component of tau 2 and its intensity I2. o-Ps pick-off annihilation (long-lived lifetime component of tau 3 and I3) within open-space defects in interlayer gaps of the adjacent rGO nanosheets. The changes in PALS parameters assigned to different types of defects are closely correlated to the mechanical and electrically conductive properties of the nacre-inspired composite papers. This work provides a general solution in PALS characterizing the microstructure of a series of graphene-based/polymer biomimetic composites.

Photocatalytic production of hydrogen peroxide (H2O2) from seawater represents a sustainable approach for solar energy conversion. However, complex ionic composition hinders charge transport and accelerates catalyst degradation, undermining efficiency and posing a major challenge to the development of effective photocatalysts. Here, we explore the role of axial symmetry in stabilized β-ketoamine covalent organic frameworks (COFs) for efficient seawater photocatalysis. Three COFs with identical chemical compositions but distinct symmetries, uniaxial (1KtTb), meta-uniaxial (2KtTb), and meta-triaxial (3KtTb), were synthesized. Comprehensive experiments and theoretical analyses reveal that axial symmetry significantly influences light absorption, photocarrier recombination, and the energy barriers of key intermediate pathways (*OOH and *OH). The uniaxial symmetric framework exhibits a narrower bandgap, improved charge separation, and lower reaction barriers, enabling enhanced solar utilization and photocatalytic performance. In real seawater tests from the Zhoushan Sea, the uniaxial symmetric COF achieved record H2O2 production rates of 12 865.2 µmol g-1 h-1 under oxygen and 8557.4 µmol g-1 h-1 in air, with over 90% activity retained after 20 cycles and 30 days of immersion. Our results demonstrate the application potential of structural symmetry in photocatalysis and guide the design of marine-adapted COFs for efficient H2O2 synthesis and photoelectric conversion.

Common organic small molecule dyes exhibit chemical modifiability and are easy to polymerize, making them potential monomers in organic electronics. The multifunctionality of organic synthetic chemistry allows for material adaptability. Here, we report the synthesis route and purification methods for dye polymer based on thiophene-diketopyrrolopyrrole. Their orderly conjugated structure and high coplanarity contribute to a high crystallinity, which is favorable for charge carrier transport. By adjusting the device structure and thin film preparation conditions, the hole transport properties of the materials were further optimized, achieving a maximum mobility of up to 0.35 cm2 V- 1 s-1. The excellent charge carrier performance reveals the potential of such material for applications in organic electronics.

Recent studies have shown that graphene oxide (GO) nanosheets can form a nacre-like bioinspired layered structure with polysaccharide of chitosan (CS), leading to composites with excellent mechanical properties. In this study, we go further steps by immobilization of Pd species (both Pd2+ and Pd0) within nacre-like bioinspired layered GO-CS composite paper-like membranes by vacuum-assisted self-assembly process to fabricate novel GO- CS-Pd composite membrane catalysts for the first time. Synergistic interactions from hydrogen bonding (between the GO nanosheets and CS chains) and ionic bonding (between the GO nanosheets and Pd2+ ions) have been efficiently achieved, resulting in significantly improvement of the mechanical properties. Meanwhile, the in-situ grown Pd0 nanoparticles were homogeneously incorporated in the interstices of the nacre-like GO-CS composite membranes. The mechanical properties, specific area performances, and Pd0 nanoparticles size of the resultant GO-CS-Pd composite membrane are mainly tuned by the loading amount of CS. The membranes are high active for Suzuki reactions of aromatic halides and phenylboronic acid with catalyst loading as low as 0.05 mol%, and can be recycled for 8 runs without significant loss of activities. Positron annihilation lifetime spectroscopy and other structural characterization methods are implemented to characterize the unique compartmentalization structure in the nacre-like composite membranes.

As an eco-friendly flame-retardant additive, magnesium hydroxide (MH) is widely employed in low-smoking, halogen-free polymer materials due to its environmentally benign nature. In order to enhance flame retardancy performance, the modified MH was modified with tetrakis(hydroxymethyl)phosphonium sulfate (THPS) by a one-pot hydrothermal method. The resulting morphology was characterized using scanning electron microscopy (SEM), and it shows the dispersion of nanometer particles and almost no aggregation. The X-ray photoelectron spectroscopy (XPS) along with Raman spectroscopy show that the THPS is connected with the Mg(OH)2 by chemical bond. The sample was incorporated into ethylene-vinyl acetate (EVA) to evaluate the flame retardancy was assessed via limiting oxygen index (LOI) and vertical burning tests (UL-94). The results show that THPS modified MH effectively enhanced the flame retardancy, achieving a V-0 rating and an LOI value of 31.3%. In addition, the composites retain good mechanical integrity. The thermal analysis with TGA and DTG shows the formation of the MgO decomposition product, along with water vapor and phosphorus-containing radicals released by modified MH in the combustion process, forming a strong flame-retardant protective layer. In addition, the maximum smoke density of EVA/MHP-3 composite was 155.4, lower than 411.3 for EVA/MH, with a 62.2% reduction in total smoke production. The result shows that THPS is effective for improving the flame-retardant efficiency of inorganic metal hydroxide in polymer composites.

N-doped porous carbon shows great potential in the field of heterogenous supports due to its high porosity, large surface area, rich active sites, and strong chelation with catalytic active metals species. Herein, we successfully prepared a novel N-doped porous carbon derived from sodium alginate/melamine blends (SAMNC) with different mass ratio through a simple carbonization and activation process. Hierarchical porous structure of the derived N-doped carbon has been confirmed with the SEM, TEM, and N2 adsorption characterization. After Na2PdCl4 solution impregnation and further reduction process, Pd0 nanoparticles have been uniformly immobilized on the SAMNC support to produce novel Pd@SAMNC catalyst. The optimal Pd@SAMNC-0.6 possesses a high N content (5.13%), Pd content (5.90%), large BET specific surface area of 1884.5 m2g-1. Positron annihilation lifetime spectroscopy (PALS) investigation of the porous carbon materials provided the sub-nano level microporous information proofs of Pd@SAMNC-0.6 had the capability to provide more active sites for reactions than commercial Pd supported on activated carbon (Pd@AC). Pd@SAMNC-0.6 catalyst showed superior catalytic efficiency in Heck coupling reaction between aromatic halides and alkenes and can be recycled for 17 runs without significant decrease in catalytic efficiency.

Inspired by "the composition of catechol and amine groups in the adhesive proteins" of marine mussel and "brick-and-mortar" structure of nacre, we use polydopamine (PDA) as "mortar", graphene oxides (GO) nanosheets as "brick", and Pd2+ ions as interfacial reinforcer, to fabricate nacre-like Pd2+ enhanced PDA functionalized GO membranes (Pd@PDA/GO) with vacuum filtration-assisted assembly method. Meanwhile, in situ reduced Pd0 nanoclusters by PDA chains were well constrained within the resultant Pd@PDA/GO artificial nacre composites. Good interfacial adhesion with dense packing of the GO nanosheets was further confirmed with sub-nano level microstructure characterization by positron annihilation lifetime spectroscopy. The microstructural evolution of the laminated composites has been probed in depth from a theoretical computational point of view using molecular dynamics (MD) simulations. The optimal Pd@PDA5/GO95 artificial nacre composite exhibits highest tensile strength of 151.6 MPa, about three times of staring GO membranes. Using as low as 0.03 mol% of Pd@PDA5/GO95 catalyst, Suzuki coupling reaction of aryl halides with phenylboronic acid can be efficiently catalyzed and recycled for 6 runs with excellent yield.

The development of stable and efficient heterogeneous Fenton oxidation for organic pollutant degradation is crucial to avoid iron sludge formation and cumbersome filtration processes. In this study, iron oxide/carbon aerogel was prepared via the sol-gel method, freeze-drying, and high-temperature carbonization using iron nitrate heptahydrate, ammonium hydroxide, and cellulose as raw materials, with polyvinylimine serving as the crosslinking agent. To enhance the pH adaptability of the catalyst, copper and cerium elements were introduced. The characterization results demonstrate the iron (III) oxide within the carbon aerogel, achieving phenol degradation efficiency exceeding 95% within 120 min. Meanwhile, the introduction of copper and cerium accelerated the degradation of phenol while maintaining a certain catalytic degradation effect at pH 5-7. In addition, the catalyst exhibited excellent recyclability, retaining 85% of its initial degradation efficiency after five reaction cycles. This work offers a new method for the development of heterogeneous Fenton catalysts.

Two thiophene-vinyl-diketopyrrolopyrrole (TVDPP)-dye-based mesopolymers, PTVDPP-TT and PTVDPP-BT, were synthesized under near-room-temperature conditions. These mesopolymers exhibit non-halogenated solution processability, high molecular coplanarity, narrow bandgaps (approx. 1.2 eV), short it-stacking distances (<3.6 & Aring;), and excellent crystallinity. They demonstrate high hole mobilities of 0.83 and 0.93 cm2 V-1 s(-1), respectively, for optoelectronic applications in field-effect transistors.

A conjugated semiconductor material with multi-alkyl chains composed of thiazole, thiophene and diketopyrrolopyrrole moieties was designed and synthesized, named PDPP-2T-2Tz. Theoretical simulations confirmed that the molecular structure exhibits excellent coplanarity, which is essential for achieving efficient charge carrier transport. A series of photophysical and electrochemical measurements were conducted to investigate its optical properties and frontier orbital energy levels. Two-dimensional grazing-incidence wide-angle X-ray scattering (2D-GIWAXS) and atomic force microscopy (AFM) results demonstrated the high crystallinity and smooth film morphology of the material. The hole mobility of the annealed film-based transistor materials reached 0.33 cm2 V−1 s−1, demonstrating its potential applications for scalable fabrication of flexible circuits.

Two-dimensional covalent organic frameworks are a unique type of organic crystals with both weak layer-layer interaction and regular one-dimensional nanochannels. Therefore, it is possible to synthesize two-dimensional covalent organic frameworks with reversible stacking phases and thus pore sizes, which hold great potential applications in future nanoelectronics, nanoreactors, intelligent response, gas separation and storage. However, such a goal remains challenging up to now, because the slipped AA-stacking is the most thermodynamically stable phase. Here, we report the realization of shape memory two-dimensional covalent organic frameworks with reversible interlayer stacking sequences, of which AA and inclined phases are induced by the formation of hot ice and the strongly adsorbed organic molecules like Tetrahydrofuran inside the two-dimensional covalent organic frameworks confined nanochannels, respectively. Based on the reversible pore sizes and pore environments, we demonstrate the feasibility of the shape memory two-dimensional covalent organic frameworks in dynamically tunable permeability and intelligent response.

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.