Organic-inorganic System Research Articles

The Study of Optimization of Flocculation and Destabilization Technology of Waste PEM Drilling Fluid in Bohai Oilfield

In light of the difficulty of solid-liquid separation of waste PEM drilling fluid in the Bohai oilfield, constructing an inorganic-organic flocculation system is proposed and the processing method of destabilization technology is optimized. The biggest influence factor on the flocculation process of PEM drilling fluid was determined by designing an orthogonal test. The flocculation mechanism was researched through single factor optimization, combined with zeta potential and particle size distribution test. The results showed that the most significant factors affecting the flocculation of waste PEM drilling fluid were the dosage of inorganic flocculant CaCl2 and flocculation pH value. When the dosage of inorganic flocculant CaCl2 was 1.2% (w/v), the dosage of organic flocculant SDYJ-2 was 0.05%, the flocculation pH value was 3, and the flocculation time was 5 min, the flocculation technology reached the optimization and then the liquid yield can reach 70.96%. The mechanism of flocculation and destabilization was as follows: the inorganic flocculant of CaCl2 mainly reduced the zeta potential of clay particles through electric neutralization. 1% CaCl2 could reduce the potential mean value of drilling fluid system from -38.1 mV to -32.5 mV, and then decrease the repulsion among suspensions. Through bridging curling and electric neutralization, the organic flocculant of SDYJ-2 can absorb and wrap the clay particles after flocculation destabilization to form a network spatial structure, which made clay particles aggregate into large flocs and particles. D50 can increase by 21.5 times, when the concentration of SDYJ-2 was 0.15%.

Combination of cardanol-derived flame retardant with SiO2@MOF particles for simultaneously enhancing the toughness, anti-flammability and smoke suppression of epoxy thermosets

In this work, an organic-inorganic flame retardant composite system was utilized by combining the renewable cardanol-based flame-retardant toughening agent (CF-PO(OPh)2) and the core-shell SiO2@MOF particles, then a series of high-performance epoxy composites with simultaneously enhanced mechanical properties, fire safety as well as smoke suppression effect were prepared with incorporating different ratio of the organic and inorganic flame retardant components. The epoxy composite containing 3% CF-PO(OPh)2 and 2% SiO2@UiO-66 (EP3) showed the most striking enhancements in the mechanical and flame retardant performances. The tensile strength and impact strength of EP3 was 48.8% and 25.3% higher than those of EP0, respectively. In view of flame retardant properties, EP3 showed maximum reductions in PHRR, SPR, CO, and CO2 productions which were 30.5%, 25.8%, 51.4%, and 43.7% lower than those of EP0, respectively. The excellent flame retardant and mechanical properties of epoxy composites resulted from the synergetic effect of cardanol-based phosphorus-containing CF-PO(OPh)2 and inorganic core-shell SiO2@UiO-66 particles.

Synthesis and characterization of hybrid nanocarrier layered double hydroxide grafted by polyethylene glycol and gemcitabine

For the past few years, organic-inorganic hybrid nanocarriers have been widely explored for effective drug delivery and preferable disease treatments. In this article, hydrothermal method was utilized to prepare fine dispersed layered double hydroxide (Mg-Al LDH) suspension. Polyethylene glycol (PEG) was grafted on the surface of LDH lamella in order to improve the dispersibility of LDH. Besides, the anti-cancer drug gemcitabine was grafted on the surface of LDH lamellas through chemical grafting. Hence a novel new type of organic-inorganic hybrid drug delivery system LDH-mPEG-Gemcitabine was obtained. In addition, the siRNA was intercalated into the LDH interlamination by ion exchange method to realize drug and gene co-delivery. The loading capacity of LDH and LDH-mPEG-Gemcitabine was evaluated by agarose gel electrophoresis. The characterization by laser particle size analyzer, TEM, FT-IR, XRD, in vitro cell viability and in vitro drug release demonstrated that LDH-mPEG-Gemcitabine possessed fine dispersibility, uniform morphology and particle size, fine biocompatibility, ideal drug loading and releasing capacity and held great potential to be used as a desired co-delivery system for drug and gene.

Novel Bionic Soy Protein-Based Adhesive with Excellent Prepressing Adhesion, Flame Retardancy, and Mildew Resistance.

Soy protein (SP)-based adhesives can replace traditional aldehyde-based adhesives for the manufacturing of wood-based panels. However, developing a SP-based adhesive with excellent prepressing bonding strength, flame retardancy, and mildew resistance remains a challenge. Herein, an inorganic crystal cross-linked hybrid SP adhesive was developed inspired by the "secreting-hardening" process of the mussel adhesive protein and the organic-inorganic hybrid adhesive system of the oyster. Calcium sulfoaluminate (CSA) was introduced into the adhesive mixture of SP and acrylic acid to induce the in situ polymerization of acrylic acid to achieve adhesive gelation. The generation of the inorganic crystals by hydration of CSA not only contributed to the formation of a stable cross-linked hybrid adhesive system for strong cohesion but also provided strong interfacial adhesion between the adhesive layers and the plywood veneers. As anticipated, the prepared plywood sample bonded with the hybrid adhesive gel had an excellent prepressing bonding strength of 544 kPa, representing a significant increase compared to that of the pure SP adhesive (19 kPa). Moreover, the generated inorganic crystals endowed the adhesive with excellent mildew resistance and flame retardancy. This study provides a novel and effective strategy for the preparation of high-performance SP-based adhesives.

A hybrid molecular sensitizer for triplet fusion upconversion

Triplet fusion upconversion is useful for a broad spectrum of applications ranging from solar cells, photoredox catalysis, to biophotonics applications, especially in the near-infrared (NIR, >700 nm) range. This upconverting system typically demands efficient conversion of spin-singlet harvested energy through intersystem crossing to spin-triplet states, accessible only in rare metallic-coordinating macrocycle compounds or heavy-metal-containing semiconductor quantum dots for triplet sensitization. Herein, we describe an organic–inorganic system for NIR-to-visible triplet fusion upconversion, interfacing commonly-seen, non-metallic, infrared dyes (IR806, IR780, indyocynine green, and CarCl) and lanthanide nanocrystal (sodium ytterbium fluoride) as a hybrid molecular sensitizer, which extracts molecular spin-singlet energy to nanocrystal-enriched ytterbium dopants at ~48% efficiency (IR806, photoexciation at 808 nm). Moreover, ytterbium sub-lattice energy migration increases the interaction possibility between the nanocrystal and the freely-diffusing rubrenes in solution, resulting in 24-fold (IR806) to 1740-fold (indocyanine green) upconversion (600 nm) increase, depending on the IR dye type, as compared to the one without ytterbium nanotransducers. Ab initio quantum chemistry calculations identify enhanced spin-orbital coupling in the ytterbium-IR806 complex and high energy transfer rate in the ytterbium-rubrene interaction (1010 s−1). Employing inorganic lanthanide nanocrystals as nanotransducers unleashes the potential use of non-metallic infrared organic dyes for triplet fusion upconversion.

Enhanced Photocatalytic Performance of Poly(3,4-ethylenedioxythiophene)- Coated TiO2 Nanotube Electrodes

This study presents the design of a mixed organic–inorganic system to be utilized in solar-light chemical energy conversion applications, where the visible-light absorption properties of the conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), are combined with the enhanced charge transport properties of TiO2 nanotubes, thus creating an efficient photoelectrode. A dispersion of PEDOT doped with p-toluenesulfonate (tosylate) ions was synthesized using a simple solution-casting polymerization process, which was then spin-coated onto an ordered array of anodically fabricated TiO2 nanotubes to be used for solar energy conversion. Electron microscopy observation confirmed the presence of PEDOT in the hybrid (PEDOT–TiO2) and Fourier transform infrared spectroscopy verified the vibrational modes of the polymerized PEDOT. The ultraviolet-visible diffuse reflectance data indicated a change in the absorption edge of the pure TiO2 nanotubes to longer wavelengths after PEDOT coating. The developed photo-electrodes exhibited a significant increase in photocurrent response and lower charge transfer resistance with respect to the pure TiO2 nanotubes, as verified by electrochemical impedance spectroscopy.

An insight into quartz mineral interactions with kerogen in Green River oil shale

Green River oil shale is an organic-inorganic macromolecular composite system. Identifying the interactions between nanoscale organic kerogen and the inorganic mineral matrix in oil shale is an important step towards the design of technologies for economic and efficient recovery of shale oil. Quartz (SiO2), one of the tectosilicate minerals present in the Green River oil shale, is modeled to determine the interactions with the 3D kerogen model. The molecular dynamics simulation technique is used as the tool for modeling the interactions. Two models with different orientations of quartz mineral and kerogen are built to evaluate the role of mineral orientation on the molecular interactions. The models are simulated at room temperature and pressure (300 K and 1.013 bar). The kerogen-quartz interactions are evaluated with respect to eight kerogen fragments. We observe that different fragments within the 3D Kerogen molecules interact with the quartz depending upon the quartz orientation. In both cases, the unconstrained ammonium (NH4) ions from the adjacent layer of kerogen migrate to the quartz cavities. All the non-interacting kerogen fragments move away from quartz. The nonbonded interactions between kerogen and quartz are generally electrostatic. The presence of quartz mineral also affects the inter-fragment and inter-layer interactions within the kerogen molecule.

Nonlinear Amplification of Chirality in Self-Assembled Plasmonic Nanostructures.

Molecular chirality transfer and amplification is at the heart of the fundamental understanding of chiral origin and fabrication of artificial chiral materials. We investigate here the nonlinear amplification effect in the chiral transfer from small molecules to assembled plasmonic nanoparticles. Our results show clearly a recognizable nonlinear behavior of the electronic and plasmonic circular dichroism activities, demonstrating the validity of the "majority-rules" principle operating in both the three-dimensional interface-confined molecularly chiral environment and the assembled plasmonic nanoparticles. Such twin "majority-rules" effects from the self-assembled organic-inorganic nanocomposite system have not been reported previously. By establishing a direct correlation between the dynamic template of the molecularly chiral environment and the nonlinear chiral amplification in the nanoparticle assemblies, this study may provide an insightful understanding of the hierarchical and cooperative chiral information transfer from molecular levels to nanoscales.

Plasmonic Ag/AgCl/NH2-MIL-88B (Fe) inorganic-organic hybridized heterojunction as visible-light-driven photocatalyst for hexavalent chromium reduction

To effectively photocatalytic removal of Cr (VI), this work focuses on constructing the inorganic-organic hybridized heterojunction composite photocatalyst of Ag/AgCl/NH2-MIL-88B (Fe), where the Ag/AgCl nanoparticles were deposited on the surface of mesoporous NH2-MIL-88B (Fe) via a simple photo-assisted reduction method. The formation of the ternary Ag/AgCl/NH2-MIL-88B (Fe) composite presented more stable and higher photocatalytic reduction performance for Cr (VI) removal than that of MIL-88B (Fe) photocatalyst. Its photo-reduction rate reached to 85.7%, which was ascribed to its high separation and migration efficiency of photogenerated electrons and holes pair. The formed heterojunction structure and surface plasmon resonance effect originated from Ag/AgCl could largely enhance the absorption capacity of visible light, which promotes the excitation of photogenerated electrons, accelerates their transfer, and reduces the recombination rate of electrons and holes. Besides, a possible catalytic mechanism of this reaction is proposed by the photo-induced charge transfer path in the Ag/AgCl/NH2-MIL-88B (Fe) inorganic-organic hybridized system.

Unraveling the Impact of Halide Mixing on Crystallization and Phase Evolution in CsPbX3 Perovskite Solar Cells

Summary All-inorganic perovskite solar cells (PSCs) have attracted wide attention for their excellent thermal stability. However, the detailed crystallization process and complicated phase-transition mechanism of the CsPbX3 film with different halide compositions (I, Br, Cl) remain mysterious. In this study, systematic investigations are performed via state-of-art in situ grazing-incidence wide-angle X-ray scattering to understand the role of the halide elements in all-inorganic perovskite crystallization kinetics, phase-transition, and stabilization mechanism as well as how film morphology and grain size are affected. Based on these results, we were able to fabricate high-performance ternary halide (I, Br, Cl) all-inorganic PSCs through a precise compositional engineering. Our results provide guidance for an in-depth understanding of all-inorganic perovskite materials and pave the way to obtain high-performance all-inorganic PSCs.

A New Scheme to Prepare Polyoxovanadate-Polymer Hybrid Materials

Polyoxovanadates (POVs) have aroused increasing attentions in recent years because of their excellent catalytic properties and unique biochemical activities. The rational design and materialization of POVs towards practical applications remain a challenge. One main strategy for the preparation of polyoxometalate-based materials is to incorporate the inorganic metal-oxo clusters into organic polymers. However, there is rare report about POV-based polymer mainly because that the vanadium with high valence state in clusters have negative impact on the design and synthesis. In this communication, we provided a new scheme to prepare POV-based polymers by stepwise functionalization and free radical polymerization for the first time. The influence from different organic ligands to the polymerization was also discussed. The results indicate that the free radical polymerization in the POV-based inorganic–organic system has the same tendency as the pure organic system, providing a new vision for the rational design of advanced POV-based polymer materials. For the first time, polyoxovanadate clusters were successfully linked to organic polymers by free radical polymerization reaction, providing a new vision for the rational design of advanced polyoxovanadate-based hybrid materials.

Lignin-based dual component additives as effective electrode material for energy management systems

A functional PbO-lignin electrode hydrid material composite was designed and manufactured. Moreover, its connection efficiency was confirmed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). We noted that the superficial layers of PbO combined with layers of the biopolymer and that oxygen atoms present in both materials had influence on the chemical environment of the neighboring compound. Hence, it can be said that the addition of PbO significantly contributes to the improvement of thermal stability of the final inorganic-organic system. In the framework of the study, the dispersive, morphological and structural characteristics were determined using scanning electron microscopy (SEM) and laser diffraction method. Electrochemical studies indicated that the PbO-lignin material exhibits better electrochemical properties compared to PbO without the addition of kraft lignin (increased capacitance, lower charge transfer resistance), as the specific capacitance after 5000 charge/discharge cycles was still at 95% of the initial value. Such promising operating parameters show that this material can be successfully used as an electrode material for energy management systems.

In situ fabrication of flower-like metallopolymeric superstructure on Nd2Fe14B template for enhanced microwave absorption

This work represents a novel study on the morphology construction in an organic-inorganic composite system for superior microwave absorption. Metallopolymeric superstructures (MPS) in situ grown on the surface of Nd2Fe14B particles can be achieved via the combination of chemical and physical synthesis methods. The as-prepared MPS@Nd2Fe14B composite presents a special flower-like appearance. The formed MPS not only acts as a lightweight component but also plays a major role in tuning the electromagnetic response capability. Upon adjusting the content of the formed MPS, the maximum reflection loss (RL) of the composite can reach up to −40.2 dB, and the broadest effective absorption bandwidth (RL < −10 dB) achieves 2.8 GHz (14.2–17.0 GHz) at a low matching thickness of 1.6 mm, which is much wider than that of pure Nd2Fe14B. The MPS@Nd2Fe14B composite possesses great potential for microwave absorption. Besides, this study provides a facile strategy for constructing functional composites with special morphology.

Organic-inorganic hybrid-photoanode built from NiFe-MOF and TiO2 for efficient PEC water splitting

Constructing the high-performance photoanode is critical to improve photoelectrochemical (PEC) efficiency, but it is still an inevitable challenge to rationally fabricate the organic-inorganic hybrid-photoanode system. For the first time, we report a novel hybrid-photoanode built from ultrathin NiFe-MOF and TiO2 by a sacrifice template method. The in-situ etch of NiFe-layered double hydroxide (LDH) on the surface of TiO2 has been successfully realized in the coordination environment, for creating coordinately unsaturated metal sites on NiFe-MOF. The coordinately unsaturated metal sites could significantly promote the water oxidation kinetic, compared with conventional electrode/electrolyte interface. The photocurrent density of the NiFe-MOF/TiO2 has reached about 3.35 times of bare TiO2 at 1.23 V (vs. RHE), and the incident photon to current conversion efficiency (IPCE) value has been improved up to 42% (at 390 nm). The significant augment of the charge injection (ηinjection) of 92.8% and charge separation (ηseparation) efficiency of 37.4% has also been exhibited. Moreover, NiFe-MOF/TiO2 shows a long-term stability ( < 10% decay) after 4 h of continuous illumination. This work provided a novel and rational strategy about the integration of the inorganic semiconductor and organic MOF, which can provide a new insight into understanding MOF-based catalysts for PEC water splitting.

Facile preparation PCL/ modified nano ZnO organic-inorganic composite and its application in antibacterial materials

Due to its good biodegradability and biocompatibility, polycaprolactone (PCL) has attracted widespread attention in the field of biomedical materials. Incorporation of Zinc oxide (ZnO) into PCL has been proved an effective way to improve its antibacterial properties. However, the interfacial compatibility of the organic-inorganic system needs to be improved due to the agglomeration of nanoparticles and phase separation of ZnO and PCL matrix affect its antibacterial efficiency. In this research, the ZnO surface was modified with citric acid monohydrate (CA) to improve the interfacial properties of ZnO-PCL system. The surface modification of ZnO was analyzed by DLS, TEM, TGA, and XPS. The results suggest that CA coating process can significantly reduce the agglomeration of ZnO nanoparticles and improve dispersion stability. The uniform PCL/ZnO-CA membranes with various nanofiller contents were fabricated through the solvent casting method. DSC and TGA analysis showed that the presence of ZnO-CA nanoparticles slightly decreased the crystallinity and thermal stability of the polymer. And ZnO-CA loaded improved the mechanical properties and wettability of the composite PCL membranes. Moreover, the composite PCL membranes showed good antibacterial activity against both E. coli and S. aureus while exhibiting good cytocompatibility, which indicated that the antibacterial and no cytotoxicity biomaterials had promising application in the biomedical field.

Spectral attributes of sub-amorphous thermal conductivity in cross-linked organic-inorganic hybrids.

Organic-inorganic hybrids have found increasing applications for thermal management across various disciplines. Such materials can achieve thermal conductivities below the so-called "amorphous limit" of their constituents' thermal conductivity. Despite their technological significance, a complete understanding of the origins of this thermal conductivity reduction remains elusive in these materials. In this paper, we develop a prototypical cross-linked organic-inorganic layered system, to investigate the spectral origins of its sub-amorphous thermal conductivity. Initially, we study the atomic structure of the model and find that besides polymer chain length, the relative drift of the layers governs the reduction in computed basal spacing, in agreement with experimental measurements. We, subsequently, find that organic cross-linking results in up to 40% reduction in thermal conductivity compared to inorganic samples. An in-depth investigation of vibrational modes reveals that this reduction is the result of reduced mode diffusivities, which in turn is a consequence of a vibrational mismatch between the organic and inorganic constituents. We also show that the contribution of propagating modes to the total thermal conductivity is not affected by organic cross-linking. Our approach paves the path toward a physics-informed analysis and design of a wide range of multifunctional hybrid nanomaterials for thermal management applications among others.

Phytic acid/silica organic-inorganic hybrid sol system: a novel and durable flame retardant approach for wool fabric

The fabrication of long-lasting flame retardant wool textiles through an eco-friendly scheme is still an urgent task. In the present study, an eco-friendly and innovative hybrid silica sol with core-shell structure was prepared by using phytic acid (PA) as catalyst and dopant for tetraethoxysilane. PA/silica organic-inorganic hybrid sol (PA/silica sol) was then employed to produce durable flame retardant wool fabric using a combined nanoparticle adsorption and pad-dry-cure procedure. The treated wool had enhanced thermal stability and greatly suppressed smoke production capacity. It could still be self-extinguishing after 30 washing cycles. The present approach brought no great negative influence on the handle and mechanical performance of wool fabric. The PA/silica sol network was found to participate in the degradation of the treated wool in the solid phase. The formation of highly inflated char during burning also revealed the flame retarding activity of the PA/silica sol on wool by a condensed charring action.

Bioinspired ZnO-Based Solar Photocatalysts for the Efficient Decontamination of Persistent Organic Pollutants and Hexavalent Chromium in Wastewater

Biomimetic/bioinspired engineering and sulfidation processes are effective strategies for improving the visible light-driven photocatalytic performance of ZnO photocatalysts. A facile electrodeposition process in high oxygen-flux conditions was used to synthesize well-defined fractal micro/nanoferns, consequently increasing the photocatalyst’s light-trapping capability and the accessible active surface. Next, a simple sulfidation process was used to form a thin layer of ZnS, producing ZnO@ZnS core@shell micro/nanoferns, thereby tuning the optoelectronic properties and extending the photoresponse to the visible region. The ZnO@ZnS micro/nanoferns exhibited clear superiority over other ZnO photocatalysts in the photooxidation of persistent organic pollutants (POPs) and the photoreduction of Cr(VI). Their excellent photocatalytic performance allowed the photodegradation under UV-filtered sunlight of nearly 97% of methylene blue after 60 min; the mineralization of &gt;98% of a mixture of methylene blue, 4-nitrophenol, and rhodamine-B after 210 min; and the removal of nearly 65% of Cr(VI) after 180 min. In addition, the ZnO@ZnS micro/nanoferns demonstrated a good ability to decontaminate an inorganic-organic bipollutant system, with promising potential to leverage synergistic effects. Finally, these micro/nanoferns presented great recyclability and reusability for both photooxidation and photoremediation processes. These findings support that sulfidation and biomimetic engineering can be a superior route for designing efficient sunlight-driven ZnO-photocatalysts for water decontamination.

PW12/CN@Bi2WO6 composite photocatalyst prepared based on organic-inorganic hybrid system for removing pollutants in water

In the drive toward green and sustainable chemistry in wastewater treatment, it is necessary to explore more efficient and stable photocatalysts to achieve the degradation of antibiotic and reduction of heavy metal ions. To this end, an organic-inorganic hybrid PW12/CN@Bi2WO6 composite photocatalyst was prepared: PW12/CN composite was prepared by heating H3PW12O40, melamine and phytic acid; PW12/CN@Bi2WO6 was synthesized via PW12/CN and Bi2WO6 by hydrothermal method. The photocatalytic activity of as-prepared photocatalyst was evaluated by degrading tetracycline hydrochloride (TC) and reducing hexavalent chromium (Cr(VI)) under the simulated xenon light source. The results show the PW12/CN@Bi2WO6 composite always maintains high catalytic performance for TC and Cr6+ and has well cycle stability. After irradiation for 90 and 100 min, the most effective 10%-PW12/CN@Bi2WO6 achieved a removal rate of 98.7% for Cr(VI) and 97.5% for TC. Photoluminescence spectroscopy and photoelectrochemical results demonstrate that the charge separation is enhanced for the PW12/CN@Bi2WO6, attributed to the introduction of the organic-inorganic systems to enhance the absorbance of light energy, promote charge transfer and inhibit e− and h+ pair recombination. In addition, the free radical scavenging test and electron spin resonance analysis (ESR) test indicate that the main species of action are h+ and O2− in the photocatalytic oxidation reaction. Further, the mechanism of photocatalysis was proposed by Mott-Schottky. The strategy improving catalytic performance through organic-inorganic hybrid systems provides a new route for the development of photocatalysts.

Organic molecule stabilized bismuth sulfide nanoparticles: A potential system for bistable resistive memory application

Abstract The performance of the microelectronic devices depends on the material used for the fabrication of the device and also the device architecture. In this paper, we demonstrate the synthesis of ‘organic molecule stabilized bismuth sulfide nanoparticles’ (BSN) by applying a one-pot, wet-chemical route. The as-synthesized material was characterized using microscopic and optical techniques. The organic-inorganic composite system displayed electronic memory effect based on the unipolar resistive switching phenomenon. The current-voltage characteristic of the device is fitted with the thermionic emission and space charge limited current model for the OFF-state, whereas, the ON-state is fitted with the combination of trapped-space charge limited current and trap-free space charge limited current model. The study of endurance and the nonvolatile behaviour of the device was performed for 103 cycles and for 2 × 103 s, respectively. The system demonstrated that the power drops do not have any impact on either ‘ON’ or ‘OFF’ state.