Inorganic Network Research Articles

In-situ sol-gel process for the formulation of Bis-GMA/TEGDMA/silica dental nanocomposite

A novel dental composite based on Bis-GMA/TEGDMA resin incorporating silica nanoparticles was developed using an innovative in situ sol-gel process. This method ensures a homogeneous dispersion of fillers, effectively preventing their agglomeration during preparation. It results in an interpenetrating network in which polymer chains and silica particles are intimately mixed, thereby enhancing the structural and mechanical properties and minimizing the volumetric shrinkage of the dental restorative material.The formation of organic and inorganic network was confirmed by infrared spectroscopy. The in situ synthesis enabled uniform dispersion of silica nanoparticles within the material as evidenced by transmission electron microscopy, scanning electron microscopy and energy dispersive spectroscopy.The results showed that the prepared composite containing 50 wt% fillers achieved hardness, modulus of elasticity, compressive strength and flexural strength values of 72 HV, 10 GPa, 240 MPa, and 110 MPa, respectively. These properties are comparable to those of the commercial “Nt Premium” composite containing 75 % preformed silica nanoparticles, which has hardness, modulus of elasticity, compressive strength and flexural strength values of 68 HV, 10 GPa, 220 MPa and 95 MPa, respectively. Additionally, the study revealed a significantly reduced volumetric shrinkage of 0.5 % for our composite, compared with over 2.2 % for Nt Premium. This groundbreaking approach holds substantial promise for developing advanced dental materials, offering superior performance and enhanced longevity in clinical applications.

Organic-Inorganic Hybrid Materials from Vegetable Oils.

The production of materials based on fossil resources is yielding more sustainable and ecologically beneficial methods. Vegetable oils (VO) are one example of base materials whose derivatives rival the properties of their petro-based counterparts. Gaps exist however and one way to fill them is by employing sol-gel processes to synthesize organic-inorganic hybrid materials, often derived from silane/siloxane compounds. Creating Si─O─Si inorganic networks in the organic VO matrix permits the attainment of necessary strength, among other property enhancements. Consequently, many efforts have been directed to optimally achieve organic-inorganic hybrid materials with VOs. However, compatibilization is challenging, and desirable conditions for matching the inorganic filler in the organic matrix remain a key stumbling block toward wider application. Therefore, this review aims to detail recent progress on these new hybrids, focusing on the main strategies to polymerize and functionalize the raw VO, followed by routes highlighting the addition of the inorganic fillers to obtain desirable composites.

Highly Conductive Supramolecular Salt Gel Electrolyte for Flexible Supercapacitors.

Conductive gels have greatly facilitated the development of flexible energy storage devices, including supercapacitors, batteries, and triboelectric nanogenerators. However, it is challenging for gel electrolytes to tackle the trade-off issues between mechanical properties and conductivity. Herein, a strategy of all inorganic salt-driven supramolecular networks is presented to construct gel electrolytes with high conductivity and reliable mechanical performance for flexible supercapacitors. The salt gel is successfully fabricated by combining a salt supramolecular network constructed by NH4Mo7O24·4H2O and FeCl3·6H2O and a polymer network of poly(vinyl alcohol). The inorganic salt supramolecular network serves as a rigid self-supporting framework in the hydrogel system for improving the mechanical properties and providing abundant active sites for accelerating ion transport. Furthermore, the salt gel-enabled supercapacitors are equipped and exhibit a high specific capacitance (199.4 mF cm-2) and excellent energy density (27.69 μWh cm-2). Moreover, the flexible supercapacitors not only present remarkable cyclic stability after 3000 charging/discharging cycles but also exhibit good electrochemical stability even under severe deformation conditions. The strategy of salt-gel-driven flexible supercapacitors would provide fresh thinking for the development of advanced flexible energy storage fields.

An organic-inorganic dual network built in fast-growing wood veneers to improve the flame retardant and mechanical properties of plywood

Fast-growing wood is widely used in plywood production due to its short growth cycle and low cost. However, its loose fiber structure, inferior material quality, and high flammability significantly limit the application range of plywood products and hinder high-value utilization. This paper reports a simple method for modifying fast-growing wood veneers. We modified phenolic resin with Mg(OH)₂@nano-silica composite particles and impregnated it into the veneers, constructing an organic-inorganic hybrid dual-network structure on both the surface and interior of the veneers. The plywood prepared from the modified veneers exhibited a bending strength of 115.6 MPa, a modulus of elasticity of 9.7 GPa, and a wet shear strength of 2.1 MPa, representing increases of 86.1 %, 47.0 %, and 90.9 %, respectively, compared to plywood made from unmodified veneers. Additionally, the peak heat release rate decreased by 15.3 %, and the ignition time was extended to 26 s. The uniformly distributed inorganic network effectively mitigated stress concentration and, together with the phenolic resin, formed an efficient thermal insulation layer, enhancing the flame retardancy of the material. This study offers a simple and effective treatment method for reinforcing fast-growing wood veneers, promoting the use of fast-growing wood in high-performance applications.

Artificial intelligence and psychedelic medicine.

Artificial intelligence (AI) and psychedelic medicines are among the most high-profile evolving disruptive innovations within mental healthcare in recent years. Although AI and psychedelics may not have historically shared any common ground, there exists the potential for these subjects to combine in generating innovative mental health treatment approaches. In order to inform our perspective, we conducted a scoping review of relevant literature up to late August 2024 via PubMed intersecting AI with psychomedical use of psychedelics. Our perspective covers the potential application of AI in psychedelic medicine for: drug discovery and clinical trial optimization (including pharmacodynamics); study design; understanding psychedelic experiences; personalization of treatments; clinical screening, delivery, and follow-up (potentially delivered via chatbots/apps); application of psychological preparation, integration, and general mental health support; its role in enhancing treatment via brain modulatory devices (including virtual reality and haptic suits); and the consideration of ethical and security safeguards. Challenges include the need for sufficient data protection and security, and a range of necessary ethical protections. Future avenues of exploration could involve directly administering psychedelics (or providing algorithm-generated effects) to inorganic AI-interfaced neural networks that may exceed human brain activity (i.e., cognitive capacity) and intelligence.

Investigation of the electronic, optical and magnetic properties of a novel two-dimensional lead-free perovskite: High visible-light absorption and long-range magnetic ordering.

Recently, big issues that need to be solved in photovoltaic solar cells area are the toxicity and instability of lead halide perovskites which have shown exceptional photoelectric performances. Herein, we report the synthesis and physico-chemical characterization of a novel two-dimensional (2D) lead-free perovskite. The 2D Cu(II)-based perovskite (C4N3H16)[CuCl4]∙Cl was successfully stabilized by the slow evaporation method under room temperature. The X-ray diffraction shows a layered structure with an inorganic network formed by four corners sharing CuCl6 octahedra. The UV-Vis absorption analysis confirms the manifestation of the cooperative Jahn-Teller effect around the Cu(II) ions. In addition to the ligand-to-metal charge transfer transitions, crystal field transitions (d-d) enhance the visible-light absorbance and make the material suitable for green solar cell applications with a band gap energy of 2.17 eV. The thermal analysis revealed the thermal stability of (C4N3H16)[CuCl4]∙Cl. Magnetic measurements revealed the presence of dominant ferromagnetic exchange interactions with J/kB = 22.85 K within the 2d planes, with a weak antiferromagnetic exchange interaction yielding a long-range magnetic ordering at 12 K.

A tough, strong, and fast-curing phenolic resin enabled by dopamine-grafted chitosan and polyethyleneimine-functionalized graphene

Phenolic resins are widely used for outdoor and structural wood-based panels; however, they are challenged by high curing temperatures, low curing rates, and high brittleness. Inspired by lobster epidermis hardening, a tough, strong, and fast-curing phenolic resin (named DCS/PG/PF) was proposed herein. In this approach, dopamine-grafted chitosan (DCS) and polyethyleneimine-functionalized graphene (PEI@G) were incorporated into neat phenol formaldehyde (PF) resin. The gel time and maximum curing temperature of DCS/PG/PF resin were considerably reduced from 445 s and 147.8 °C for the neat PF resin to 317 s and 127.8 °C, respectively. This was attributed to the oxidative crosslinking of catechol moieties in DCS and amino groups in PEI@G within the naturally alkaline environment of phenolic resins in addition to the high reactivity between catechol moieties and PF chains as well as between amino and PF chains. The prepared resin demonstrated a dry bonding strength of 2.56 MPa, wet bonding strength of 1.81 MPa, and debonding work of 0.714 J, exhibiting a considerable increase of 16.9 %, 52.1 %, and 95.1 %, respectively, compared with those of the PF resin. These improvements were attributed to the dense organic–inorganic hybrid crosslinking network formed in the DCS/PG/PF. Furthermore, the DCS/PG/PF resin exhibited enhanced thermal stability.

Hydrogels and Aerogels for Versatile Photo-/Electro-Chemical and Energy-Related Applications.

The development of photo-/electro-chemical and flexible electronics has stimulated research in catalysis, informatics, biomedicine, energy conversion, and storage applications. Gels (e.g., aerogel, hydrogel) comprise a range of polymers with three-dimensional (3D) network structures, where hydrophilic polyacrylamide, polyvinyl alcohol, copolymers, and hydroxides are the most widely studied for hydrogels, whereas 3D graphene, carbon, organic, and inorganic networks are widely studied for aerogels. Encapsulation of functional species with hydrogel building blocks can modify the optoelectronic, physicochemical, and mechanical properties. In addition, aerogels are a set of nanoporous or microporous 3D networks that bridge the macro- and nano-world. Different architectures modulate properties and have been adopted as a backbone substrate, enriching active sites and surface areas for photo-/electro-chemical energy conversion and storage applications. Fabrication via sol-gel processes, module assembly, and template routes have responded to professionalized features and enhanced performance. This review presents the most studied hydrogel materials, the classification of aerogel materials, and their applications in flexible sensors, batteries, supercapacitors, catalysis, biomedical, thermal insulation, etc.

One-Pot Synthesis of Organic–Inorganic Network Hydrogels with High Extensibility, Self-Healing, Self-Adhesive, 3D-Printing, and Antibacterial Properties

One-Pot Synthesis of Organic–Inorganic Network Hydrogels with High Extensibility, Self-Healing, Self-Adhesive, 3D-Printing, and Antibacterial Properties

Inorganic–organic polymer networks derived from a cyclic siloxane tetrafunctional glycidyl ether resin

AbstractA tetrafunctional glycidyl ether cyclic siloxane epoxy resin (TGTS) has been synthesized, characterized and cured with four aromatic amine hardeners: 1,3‐phenylenediamine (PDA), diethyltoluenediamine (DETDA), 4,4‐diaminodiphenylmethane (DDM) and 1,3‐bis(4‐aminophenoxy)benzene (APB). Each of the cured networks produces transparent and homogeneous networks, although when TGTS is cured with DETDA, reduced compatibility led to lower epoxide consumption, a more heterogenous microstructure and deleterious effects upon properties. Reduced miscibility of DETDA significantly impacts the chemical structure and microstructure of the network, resulting in significant reductions in thermal and mechanical properties but higher UV‐A transmission. The PDA‐, APB‐ and DDM‐cured networks conversely were more miscible and display properties typical of organic–inorganic hybrid networks, such as good mechanical properties at ambient and sub‐ambient temperatures, comparatively high glass transition temperatures, improved resistance to oxidation and lower UV‐A transmission. © 2024 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Robust Transparent Photothermal Omniphobic Coating for Efficient Anti/Deicing and Antifogging.

Icing and fogging on optical material surfaces bring various problems in daily life. Recently, some photothermal coatings have been reported to prevent the condensation or freeze of water droplets by increasing the surface temperature. However, it is a great challenge to apply them in practical conditions due to their opaqueness and poor mechanical wear-resistant property. In this work, we constructed a robust transparent photothermal omniphobic coating with a simple dip-coating technique. In the coating system, photothermal polypyrrole nanoparticles are introduced into inorganic silica networks, and then polydimethylsiloxane (PDMS) brushes were grafted on the inorganic silica layer to endow the surface with omniphobicity and stain resistance. The transparency and photothermal capacity of the coating can be regulated by the deposition times of the coating. In addition, the coating has an excellent anti/deicing property and reduces ice adhesion obviously due to the existence of "liquid-like" PDMS brushes. More importantly, the coating presents outstanding mechanical wear-resistant and self-lubricating properties that can endure several thousand friction cycles without performance loss. The mechanically robust photothermal omniphobic coating gives a feasible approach to anti-icing and antifogging of transparent substrates under sunlight irradiation.

Confinement of Sustainable Carbon Dots Results in Long Afterglow Emitters and Photocatalyst for Radical Photopolymerization.

Sustainable carbon dots based on cellulose, particularly carboxymethyl cellulose carbon dots (CMCCDs), were confined in an inorganic network resulting in CMCCDs@SiO2. This resulted in a material exhibiting long afterglow covering a time frame of several seconds also under air. Temperature-dependent emission spectra gave information on thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) while photocurrent experiments provided a deeper understanding of charge availability in the dark period, and therefore, its availability on the photocatalyst surface. The photo-ATRP initiator, ethyl α-bromophenylacetate (EBPA), quenched the emission from the millisecond to the nanosecond time frame indicating participation of the triplet state in photoinduced electron transfer (PET). Both free radical and controlled radical polymerization based on photo-ATRP protocol worked successfully. Metal-free photo-ATRP resulted in chain extendable macroinitiators based on a reductive mechanism with either MMA or in combination with styrene. Addition of 9 ppm Cu2+ resulted in Mw/Mn of 1.4 while an increase to 72 ppm improved uniformity of the polymers; that is Mw/Mn=1.03. Complementary experiments with kerria laca carbon dots confined materials, namely KCDs@SiO2, provided similar results. Deposition of Cu2+ (9 ppm) on the photocatalyst surface explains better uniformity of the polymers formed in the ATRP protocol.

Der Einschluss von nachhaltigen Kohlenstoffpunkten führt zu langnachleuchtenden Emittern und zu Photokatalysatoren für die radikalische Photopolymerisation

AbstractNachhaltige Kohlenstoffpunkte auf der Basis von Cellulose, insbesondere Carboxymethylcellulose basierende Kohlenstoffpunkte (CMCCDs), wurden in ein anorganisches Netzwerk eingeschlossen, was zur Bildung von CMCCDs@SiO2 führte. Das resultierende Material zeigte ein lange anhaltendes Nachleuchten, welches ein Zeitfenster von mehreren Sekunden auch in Gegenwart von Luft umfasste. Temperaturabhängige Emissionsspektren gaben eine Information über die thermisch aktivierte verzögerte Fluoreszenz (TADF) und eine Phosphoreszenz bei Raumtemperatur (RTP), während Experimente zur photoinduzierten Generierung von Ladungsträgern zu einem tieferen Verständnis der Verfügbarkeit von Ladungen in der Dunkelphase führten und daher zu ihrer Verfügbarkeit an der Katalysatoroberfläche. Der photo‐ATRP Initiator α‐Bromphenylethylacetat (EBPA) bewirkte eine Löschung der Emission, was zu einer Verkürzung des Zeitfensters für die Emission vom Millisekundenbereich in den Nanosekundenbereich führte und auf eine Beteiligung des Triplettzustandes an dem photoinduzierten Elektronentransfer (PET) hinweist. Sowohl die freie radikalische Polymerisation als auch die kontrollierte auf einem photo‐ATRP Protokoll basierende radikalische Polymerisation von MMA oder in Kombination mit Styren funktionierten erfolgreich. Die metallfreie photo‐ATRP führte basierend auf einem reduktiven Mechanismus zu einem kettenverlängerbaren Makroinitiator. Die Zugabe von 9 ppm Cu2+ führte zu einem Verhältnis Mw/Mn von 1.4 obwohl eine Erhöhung auf 72 ppm die Einheitlichkeit der Polymere verbesserte, was einem Mw/Mn=1.03 entspricht. Ergänzende Experimente mit in kerria laca eingeschlossenen Kohlenstoffpunkten, insbesondere KCDs@SiO2, führten zu ähnlichen Ergebnissen. Die Abscheidung von Cu2+ (9 ppm) an der Photokatalysatoroberfläche erklärt die bessere Dispersität der Polymere, welche mittels der ATRP gebildet wurden.

Sonocatalysis: Eco-design strategy for developing novel inorganic sonogels for the conservation of stone heritage

Products designed to form continuous inorganic networks from alkoxysilanes frequently include organic solvents because of the necessity to turning the precursors miscible with water and because dilution is required for certain applications. Thus, there is a demand for efficient mixtures employing eco-design strategies. This study explores the feasibility of sonocatalysis to prepare homogeneous mixtures with water to initiate sol-gel reactions and as the dilution agent. The approach allowed to design and prepare viable mixtures with unique tetraethoxysilane(TEOS):H2O ratios (1:4 to 1:32). By managing the ultrasonic irradiation parameters, it was possible to formulate mixtures with high degree of hydrolysis, appropriate condensation ratios, and capable to create sonogel materials containing other desired features for stone conservation. The water content manages the gelling times and gel deposition rates through a dilution effect, which might be useful to minimize undesirable side effects of conservation treatments, such as excessive pore occlusion. For instance, a TEOS:H2O ratio of 1:32 results in a very low gel deposition rate.Furthermore, the applicability and efficacy of successful mixtures was preliminary assessed, and it was demonstrated that the resulting inorganic networks, primarily composed of SiOSi bonds, can enhance the hardness and surface resistance of soft stones. This potential strengthening effect improves gradually with increasing TEOS:H2O ratios. The mixtures deserve further studies aimed at enhancing understanding of their consolidation characteristics.The advances achieved also opens the door for producing innovative dual-role hybrid inorganic-organic sonogels that can be used for materials protection and surface consolidation.

Intense-Light Sensing Yarns Achieved by Interfused Inorganic Halide Perovskite Nanofiber Network

Intense-Light Sensing Yarns Achieved by Interfused Inorganic Halide Perovskite Nanofiber Network

Synthesis and Characterisation of Hemihydrate Gypsum-Polyacrylamide Composite: A Novel Inorganic/Organic Cementitious Material.

This study combined inorganic α-hemihydrate gypsum (α-HHG) with organic polyacrylamide (PAM) hydrogel to create a novel α-HHG/PAM composite material. Through this facile composite strategy, this fabricated material exhibited a significantly longer initial setting time and higher mechanical strength compared to α-HHG. The effects of the addition amount and the concentration of PAM precursor solution on the flowability of the α-HHG/PAM composite material slurry, initial setting time, and mechanical properties of the hardened specimens were investigated. The structural characteristics of the composite material were examined using XRD, FE-SEM, and TGA. The results showed that the initial setting time of the α-HHG/PAM composite material was 25.7 min, which is an extension of 127.43% compared to that of α-HHG. The flexural strength and compressive strength of the oven-dried specimens were 23.4 MPa and 58.6 MPa, respectively, representing increases of 34.73% and 84.86% over values for α-HHG. The XRD, FE-SEM, and TGA results all indicated that the hydration of α-HHG in the composite material was incomplete. The incompleteness is caused by the competition between the hydration process of inorganic α-HHG and the gelation process of the acrylamide molecules for water, which hinders some α-HHG from entirely reacting with water. The enhanced mechanical strength of the α-HHG/PAM composite material results from the tight interweaving and integrating of organic and inorganic networks. This study provides a concise and efficient approach to the modification research of hemihydrate gypsum.

Perovskite versus Nonperovskite: Modulating the Nature and Optical Properties of One-Dimensional Chiral Lead-Bromide Networks.

In the last 5 years, low-dimensional chiral metal-halide semiconductors have attracted great interest in the generation of chiroptical activity. Among this new family of materials, one-dimensional (1D) networks have appeared as the best candidates for strong circular dichroism (CD) and circularly polarized luminescence (CPL). Here, we present a new family of 1D chiral lead-bromide materials prepared from organic S/R/rac-1-hydroxypropyl-2-ammonium (S/R/rac-HP2A) cations. The presence or absence of polarity in the crystal structure as well as the perovskite or nonperovskite nature of the inorganic network depends on the initial stoichiometry of metal-halide salt and chiral amine during the crystallization. The perovskite-type networks exhibit strong CD and second harmonic generation (SHG) responses, while the nonperovskite compounds show the presence of polymorphism in the crystal phase and weak natural optical activity in the final material. These results underline the impact of synthetic conditions and thin film morphology on the structural and optical properties of metal-halide hybrid networks.

Exploring a new vanadophosphate Li(C4N2H12)2[(HPO4)(VO)3(PO4)3]: Synthesis, Characterization, and catalytic behavior

Li(C4N2H12)2[(HPO4)(VO)3(PO4)3], a new vanadophosphate (VPO) material we synthesized using a hydrothermal route, crystallizes in the orthorhombic system (S.G.: Pna21), with the cell parameters: a = 14.6207(7) Å, b = 8.7090(3) Å, c = 17.6208(7) Å, V = 2243.69(16) (Å3), Z = 4. The crystal structure consists of bc-parallel layers of alternating polyhedra VO5, VO6 combined with PO4 or HPO4 tetrahedra. The layers stack provides cavities hosting Li+ cations. Within the interlayer space, protonated organic molecules act as a template and create hydrogen bonding interactions with the inorganic network. To assess its properties, the hybrid material’s thermal stability and reactivity were investigated using the IR spectroscopy and thermal analysis (TG/DTA). The potential of the title compound was investigated on the adsorptive removal of methylene blue (MB) dye by studying various parameters like pH, temperature, initial dye concentrations and contact time. The kinetic study revealed a gradual process of the dyés adsorption, with a removal efficiency of 99 % for initial MB concentrations of 50 ppm at pH = 7. The degradation MB continues even after three hours of oxidative reaction.

Biomimetic metal-phenolic network with cyclolactam hydrogel coating on PPENK implant facilitate bone repair

Bone defects are often accompanied by infection, which causes great physical pain to patients. Metal-phenolic networks (MPNs) are a newly organic–inorganic hybrid networks system, which has become a multifunctional surface modifier based on the universal adhesion properties of phenolic molecules. Hence, we fabricate a MPN hydrogel coating based on cyclolactam network by spin-coating a mixture of gelatin, iron ions, and polyphenol monomer containing phthalazinone structure (THPZB) on the surface of poly(aryl ether nitrile ketone) (PPENK) (G/THPZB/Fe/PPENK). The method can easily obtain a high strength and versatile surface hydrogel coating based on the combination of the entangled structure on phthalazinone and the characteristic functions of MPNs. The residual polyphenol on the surface not only confer good adhesion ability, but also can cooperate with lactam ring to confer outstanding antibacterial ability to the PPENK implant. Importantly, the antibacterial mechanism of this modified PPENK implant might be consistent with that of penicillin. Besides, it has excellent ability to promote angiogenesis and healing in vitro. Notably, significant effects on biomineralization and osteogenesis in vitro and in vivo are observed. We hypothesis that cyclolactam-based MPN multifunctional hydrogel coating can provide great application prospects for PPENK bone implant materials in the field of bone defect repair.

Self-Trapped Exciton Emission Enhancement in 3D Cationic Lead Halide Hybrids Via Phase Transition Engineering.

Three-dimensional (3D) cationic lead halide hybrids constructed by organic ions and inorganic networks via coordination bonds are a promising material for solid-state lighting due to their exceptional environmental stability and broad-spectrum emission. Nevertheless, their fluorescence properties are hindered by the limited lattice distortion from extensive connectivity within the inorganic network. Here, a dramatic 100-fold enhancement of self-trapped exciton (STE) emission is achieved in 3D hybrid material [Pb2Br2][O2C(CH2)4CO2] via pressure-triggered phase transition. Notably, pressure-treated material exhibits a 110 nm redshift with 1.5-fold enhancement compared to the initial state after pressure was completely released. The irreversible structural phase transition intensifies the [PbBr3O3] octahedral distortion, which is highly responsible for the optimization of quenched emission. These findings present a promising strategy for improving the optical properties of 3D halide hybrids with relatively high stability and thus facilitate their practical applications by pressure-driven phase transition engineering.