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The synthesis and guest recognition properties of a neutral Pd24‐cubic cage, [{Pd3(NiPr)3PO}8(μ2‐Cl)24] 1 are reported. The formation of the cubical assembly takes place by an exclusive one‐pot ligand‐assisted pathway directed by an oximido linker. The initial coordination of the oximido ligand pre‐organizes the [Pd3(NiPr)3PO]3+ polyhedral building units into a tetrameric intermediate, which then transforms into an oximido‐tethered tetrahedral assembly and to the cubical cage 1 in the presence of chloride ions. In the absence of the directing oximido linker, no cage formation was observed, and the Pd6‐precursor was found to undergo self‐condensation, giving rise to a new pentameric polyhedral cluster, [Pd5{(NiPr)3PO}2(OAc)2(OH)2] 2. The central cavity of the cube has been probed for guest encapsulation studies, which shows a high binding with phenolic guest molecules with association constants of the order of 104–105 M−1. The favorable formation of host–guest complexes was attributed to the strong hydrogen bonding interactions between the host and guest functional groups. [ABSTRACT FROM AUTHOR]

Metal Nanoclusters (MNCs) have shown great potential applications in the field of food safety due to their unique physical and chemical properties. Through the template synthesis method, the specific size, shape and dispersion of MNCs can be regulated, thereby improving their functional characteristics. Based on the recent studies on MNCs, the mechanism of template-assisted synthesis of MNCs and their applications in the detection of food contaminants, food packaging materials, antimicrobial agents and food additives are reviewed. It provides a scientific basis for template synthesis of MNCs, and to provide insights and directions for MNCs in food safety monitoring.

Peptide‐based nanofibers are promising materials for many essential applications and can be generalized into two categories, self‐assembling peptide nanofibers (SAPNs) and poly(amino acid) nanofibers (PAANs). Non‐covalent SAPNs are sequence‐controllable, but poorly stable and not suitable for post‐modification. While covalent PAANs are post‐modifiable, however, their sequences are either monotonic or undefined. The nanofibers obtained by head‐to‐tail covalent coupling polymerization of sequence‐known peptides, which we call series‐connected peptide nanofibers (SCPNs), promise to have the advantages of both SAPNs and PAANs, but they are barely reported. The undesired backbiting effect during the head‐to‐tail polymerization is one of the possible challenges. Here, we present a template‐assisted strategy to trigger the flexible‐to‐rigid transition of peptide units, which can avoid the backbiting effect and enable consecutive intermolecular polymerization of peptides to produce desired sequence‐controlled covalent SCPNs. SCPNs are highly stable and can function as excellent parent materials for various post‐processing to create diverse hierarchical materials independent of the peptide sequence. Moreover, SCPNs allow for the display of predetermined functional groups at regular intervals along the nanofibers by pre‐modification of the initial peptide sequence. SCPNs represent a new category of peptide‐based nanofibers with outstanding performances and vast potential. [ABSTRACT FROM AUTHOR]

Cadmium selenide (CdSe) represents a direct-bandgap semiconductor belonging to the II–VI group, operating within the visible range of the electromagnetic spectrum. Nanowires composed of CdSe hold significant potential for various optoelectronic applications. Employing ion implantation is an immensely appealing technique, which allows for a controlled introduction of dopants into any lattice, and it is based on well-established principles. In this context, the current investigation focuses on the impact of argon ion implantation on cadmium selenide nanowires with a diameter of 80 nm. The nanowires were synthesized via a template-assisted electrodeposition method using polycarbonate membranes with 80 nm pores and 10 µm thickness. A three-electrode setup facilitated their fabrication. Subsequently, argon ions with a 4+ charge state and an energy of 1 MeV were implanted into the synthesized nanowires at varying fluence levels, ranging from 1011 to 1013 ions/cm2. The ion implantation process was conducted in the radiation chamber of the Inter-University Accelerator Centre's low-energy ion implantation facility in New Delhi, India. Stopping and Range of Ions in Matter (SRIM) code simulations were employed to determine the optimal implantation parameters. Compositional analysis confirmed the successful incorporation of argon ions into the CdSe lattice. Notably, scanning electron microscopy revealed no alterations in the nanowire morphology despite the implantation. X-ray diffraction analysis showed no shift in the 2θ position of diffraction peaks, but indicated variations in their intensities. Furthermore, the implanted nanowires exhibited an increased absorbance and improved conductivity with increasing ion fluence. These findings demonstrate the effectiveness of argon ion implantation in modifying the optical and electrical properties of 80 nm diameter CdSe nanowires. [ABSTRACT FROM AUTHOR]

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The one-pot template reaction between 2-(diphenylphosphino)benzaldehyde, benzylamine and copper(I) iodide yields the dinuclear copper complex (P∩N)2Cu2I2, as revealed by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

The aim of the research was to prepare silica adsorbents using an environmentally friendly pathway, a template synthesis with saponin biosurfactant as a structure-directing agent. The adsorbents prepared in this way exhibit improved adsorption properties while maintaining environmental innocuousness. For the preparation of porous silica, the biosurfactant template sol–gel method was used with tetraethoxysilane as a silica precursor. The silica adsorbents were analyzed by FTIR spectroscopy, nitrogen adsorption–desorption and SEM/EDX microscopy, TEM/HRTEM microscopy, and thermogravimetric analyses. Batch tests were carried out to remediate Pb(II)/Cd(II) ions in single/binary aqueous solutions, and the effect of the surfactant on the adsorption properties was assessed. The optimal adsorption parameters (pH, contact time, initial concentration of metal ions) have been determined. The adsorption was fitted using Langmuir and Freundlich adsorption isotherms and kinetic models. Mathematical modeling of the retention process of Pb(II) and Cd(II) ions from binary solutions indicated a competitive effect of each of the two adsorbed metal ions. The experimental results demonstrated that saponin has the effect of modifying the silica structure through the formation of pores, which are involved in the retention of metal ions from aqueous solutions and wastewater. [ABSTRACT FROM AUTHOR]

The magnetic and optical properties of gold-coated nickel nanotubes obtained by template synthesis have been studied. A change in the relative intensity of an optical beam passing through a solution of nanotubes in a magnetic field perpendicular and parallel to the beam propagation shows the possibility of orienting nanotubes along the magnetic field. The results provide an assessment of the applicability of such nanotubes in combined photothermal and magnetomechanical anticancer therapy. [ABSTRACT FROM AUTHOR]

This work discusses ceramic filter materials used as substrates to study biological objects by electron microscopy. The composition, structure, pore sizes, and morphology of ceramic substrates made of foamed silicate prior to and following the application of inverse silicon oxide opals were evaluated by x-ray diffraction analysis and SEM method. Adescription of the use of the obtained filtering substrates in an experiment with biological objects is given. The substrates seem promising for electron microscopy, since they can be used for sample preparation of biological objects with the use of metal spraying or ionic liquid. This technique, together with the filtering porous material and the technical capabilities of the microscope, preserves the physical characteristics of biological objects. [ABSTRACT FROM AUTHOR]

We present the synthesis of acrylic-resin-based tubular micromotors incorporating layers of magnetite nanoparticles (MNPs) and catalase (Cat) on the inner pore surface (Cat tube micromotors) and investigate their distinctive self-propulsion capabilities modulated by visible light irradiation. In an aqueous H2O2 solution, the Cat tubes demonstrate autonomous movement by expelling O2 bubbles from their opening ends. The propulsion velocity reaches its maximum at the optimal pH and temperature for the Cat enzyme activity. Remarkably, the swimming velocity undergoes rapid acceleration upon exposure to visible light and promptly decelerates upon the cessation of illumination. This phenomenon is ascribed to the photothermal effect induced by the MNPs, elevating the temperature of the adjacent Cat layer and thereby enhancing enzyme activity. The micromotors exhibit recurrent acceleration and deceleration in response to on/off light irradiation, showcasing a high degree of sensitivity and responsiveness. [ABSTRACT FROM AUTHOR]

The synthetic availability of molecular water oxidation catalysts containing high-valent ions of 3d metals in the active site is a prerequisite to enabling photo- and electrochemical water splitting on a large scale. Herein, the synthesis and crystal structure of diammonium {μ-1,3,4,7,8,10,12,13,16,17,19,22-dodecaazatetracyclo[8.8.4.13,17.18,12]tetracosane-5,6,14,15,20,21-hexaonato}ferrate(IV) acetic acid trisolvate, (NH4)2[FeIV(C12H12N12O6)]·3CH3COOH or (NH4)2[FeIV(L–6H)]·3CH3COOH is reported. The FeIV ion is encapsulated by the macropolycyclic ligand, which can be described as a dodeca-aza-quadricyclic cage with two capping triazacyclohexane fragments making three five- and six six-membered alternating chelate rings with the central FeIV ion. The local coordination environment of FeIV is formed by six deprotonated hydrazide nitrogen atoms, which stabilize the unusual oxidation state. The FeIV ion lies on a twofold rotation axis (multiplicity 4, Wyckoff letter e) of the space group C2/c. Its coordination geometry is intermediate between a trigonal prism (distortion angle φ = 0°) and an antiprism (φ = 60°) with φ = 31.1°. The Fe—N bond lengths lie in the range 1.9376 (13)–1.9617 (13) Å, as expected for tetravalent iron. Structure analysis revealed that three acetic acid molecules additionally co-crystallize per one iron(IV) complex, and one of them is positionally disordered over four positions. In the crystal structure, the ammonium cations, complex dianions and acetic acid molecules are interconnected by an intricate system of hydrogen bonds, mainly via the oxamide oxygen atoms acting as acceptors.

Porous α-Fe2O3 hollow rods/reduced graphene oxide (α-Fe2O3 HR/RGO) composites with unique morphological characteristics and a high surface area are prepared through a template strategy, which was systematically studied and found to have outstanding supercapacitive properties. When served as active material in a three-electrode setup, the optimized α-Fe2O3 HR/RGO-30, comprised 76.5 wt% α-Fe2O3 and 23.2 wt% RGO, was able to offer the largest specific capacitance of 426.3 F g−1, an excellent rate capability as well as satisfactory cycle life with capacitance retention of 87.7% and Coulombic efficiency of 98.9% after continuously charging/discharging at 10 A g−1 for beyond 10,000 cycles. Such electrochemical behaviors of the α-Fe2O3 HR/RGO-30 electrode can rival or even surpass those of many Fe2O3-based electrodes documented in the previous literature. Later, a symmetric supercapacitor cell of α-Fe2O3 HR/RGO-30//α-Fe2O3 HR/RGO-30 was fabricated. The assembled device offers the maximum energy density of 18.7 Wh kg−1, and also exhibits commendable rate capability, and features stable cycling durability (with capacitance retention of 83.2% together with a Coulombic efficiency of 99.3% after 10,000-cycle charge/discharge at 5 A g−1). These notable electrochemical performances enable the α-Fe2O3 HR/RGO-30 composite to be a high-potential material for advanced energy storage systems. [ABSTRACT FROM AUTHOR]

The catalytic properties of materials based on terbium-doped and nickel-modified mesoporous silica gels prepared by the high-temperature template method were studied. The surface morphology and textural characteristics of the obtained samples were studied by scanning electron microscopy, X-ray phase analysis, and inductively coupled plasma mass spectrometry. The catalytic activity of the obtained catalysts was studied in the hydrogenation reaction of benzene, m-, p-, and o-xylene in the temperature range of 80–170°C and at a hydrogen pressure of 3 atm. It was established that doping with terbium leads to an increase in the catalytic activity of the catalyst modified with nickel in the hydrogenation reaction of benzene derivatives. Therefore, it was shown that mesoporous silica gel doped with terbium and modified with nickel is an effective catalyst for the hydrogenation of benzene and xylenes. [ABSTRACT FROM AUTHOR]

The application of supramolecular templates in aligning atomically precise heterometal arrays is important for pursuing functional materials. Herein, we report that a bilayered supramolecular tri‐deprotonated melamine dimer functions as an effective template in the construction of a heterometallic gold(I)‐silver(I) macrocyclic cluster [μ6‐(C3N6H3)3−]2−AuI6AgI6. X‐ray single crystal structural analysis showed that a crown‐like AuI6AgI6 macrocycle is aligned around two parallelly stacked μ6‐(C3N6H3)3− moieties hold together with π–π interactions. Theoretical calculations revealed that the [μ6‐(C3N6H3)3−]2 motif dominantly contributes to the near‐occupied orbitals in the electronic structure, which is closely related to its luminescence properties. This work demonstrates that the supramolecular templates containing multiple symmetric binding sites may present a facile approach in the construction of functional metal clusters. [ABSTRACT FROM AUTHOR]

The graphical abstract shows a typical phase diagram for a polymerizable SFME system. The area in which SFMEs can be expected is marked in blue. Three SEM images of polymers and their area of origin are given: droplet-like polymers from o/w-like SFME, sponge-like polymers from w/o-like SFME, and a polymer without observable nanostructures from the region where no mesostructures were found before polymerization. [Display omitted] Surfactant-free microemulsions (SFMEs) were recently reported to be an interesting medium for free-radical polymerizations. The aim of this study is to investigate the link between the morphology of PMMA monopolymers as well as PMMA-PHEMA-copolymers with the expected nature of the SFME before polymerization. A surfactant-based microemulsion with nonionic surfactants was investigated as a reference system. It is expected that the kind of mesostructuring of the SFME (oil-in-water-like, bicontinuous, inverse) corresponds with the latter polymer morphology, just like it is the case in surfactant-based systems. Simple SFME systems composed of water, a hydrotrope (isopropanol or tert -butyl alcohol), and methyl methacrylate (MMA) as polymerizable oil as well as the more complex system comprising 2-hydroxyethyl methacrylate (HEMA) as an additional amphiphilic co-monomer, were investigated. A surfactant-based system using a mixture of Tergitol 15-S-12 and Synperonic A11-LQ-(TH) as surfactants, water, and MMA in the presence and absence of HEMA as polymerizable co-surfactant was investigated as a reference system. Structural analysis was done by recording (pseudo-)ternary phase diagrams, dynamic light scattering (DLS), and conductivity measurements. Polymerizations were performed using the oil-soluble initiator PEROXAN BCC at 318 K for 24 h with adjacent lyophilization. The morphology of dried polymers was determined by light microscopy, scanning electron microscopy, and BET adsorption isotherms. Porous polymers of different morphologies (from coagulations of droplet-like aggregates to sponge-like ones) in the size range of 200 nm up to some µm can be derived from previously mesostructured, surfactant-free mixtures. Previously unstructured, oil-rich regions lead to solid, transparent polymers without nanostructured morphologies. The surfactant-based reference system comprises remarkably similar phase behavior before polymerizations and similar polymer morphologies as the comparable surfactant-free system. This leads to the assumption that the hydrotropic behavior of HEMA and its interplay with MMA and water is the structure-giving factor in this system. [ABSTRACT FROM AUTHOR]

This study presents a method for fabricating a film-based heating element using a polymer material with an array of intersecting conductive elements embedded within it. Track-etched membranes (TM) with a thickness of 10 μ m were used as the template, and their pores were filled with metal, forming a three-dimensional grid. Due to the unique manufacturing process of TM, the pores inside intersect with each other, allowing for contacts between individual nanowires (NWs) when filled with metal. Experimental results demonstrated that filling the TM pores with silver allows for heating temperatures up to 78 degrees without deformation or damage to the heating element. The resulting flexible heating element can be utilized in medical devices for heating purposes or as a thermal barrier coating. [ABSTRACT FROM AUTHOR]

The synthetic availability of molecular water oxidation catalysts containing highvalent ions of 3d metals in the active site is a prerequisite to enabling photo- and electrochemical water splitting on a large scale. Herein, the synthesis and crystal structure of diammonium {μ-1,3,4,7,8,10,12,13,16,17,19,22-dodecaazatetracyclo[ 8.8.4.1³,17.18,12]tetracosane-5,6,14,15,20,21-hexaonato}ferrate(IV) acetic acid trisolvate, (NH4)2[FeIV(C12H12N12O6)]·3CH3COOH or (NH4)2[FeIV(L-6H)]·3CH3COOH is reported. The FeIV ion is encapsulated by the macropolycyclic ligand, which can be described as a dodeca-aza-quadricyclic cage with two capping triazacyclohexane fragments making three five- and six sixmembered alternating chelate rings with the central FeIV ion. The local coordination environment of FeIV is formed by six deprotonated hydrazide nitrogen atoms, which stabilize the unusual oxidation state. The FeIV ion lies on a twofold rotation axis (multiplicity 4, Wyckoff letter e) of the space group C2/c. Its coordination geometry is intermediate between a trigonal prism (distortion angle φ = 0°) and an antiprism (φ = 60°) with φ = 31.1°. The Fe--N bond lengths lie in the range 1.9376 (13)-1.9617 (13) Å, as expected for tetravalent iron. Structure analysis revealed that three acetic acid molecules additionally cocrystallize per one iron(IV) complex, and one of them is positionally disordered over four positions. In the crystal structure, the ammonium cations, complex dianions and acetic acid molecules are interconnected by an intricate system of hydrogen bonds, mainly via the oxamide oxygen atoms acting as acceptors. [ABSTRACT FROM AUTHOR]

The one-pot template reaction between 2-(diphenylphosphino)benzaldehyde, benzylamine and copper(I) iodide yields the dinuclear copper complex (P∩N)2Cu2I2, as revealed by single-crystal X-ray diffraction.

Here, we propose a drug delivery system for ciprofloxacin (CF) based on cyclodextrin (CD) polymer. We obtained a 3D matrix system with encapsulated drug molecules by crosslinking CF+CD non-covalent complexes with 1.6-hexamethylene isocyanate. The obtained polycarbamide (MAX-system) represents particles (~225 nm in diameter) that demonstrate CF’s sustained release. We investigated how the carrier affects the drug’s interaction with the biological macromolecule human serum albumin (HSA) and CF’s antibacterial properties. Compared to a binary CF–HSA system, CD decreases CF’s binding efficiency to HSA by two times, whereas CF encapsulation in a polymer matrix doubles the Ka value and prevents protein aggregation. The changes in HSA’s secondary structure indicate no alterations in the main mechanism of complex formation between CF and HSA in the presence of both CD-based carriers. CD as well as MAX systems practically do not change CF’s activity against E. coli and B. subtilis, but for MAX systems, prolonged action is realized due to CF’s sustained release. We believe that our findings are important for the further development of new, efficient drug forms.

Metal oxide porous nanomaterials are of great interest across scientific fields due to their intriguing properties, allowing their usage from lab-scale research to industrial applications. However, the production of high surface area metal oxide nanomaterials still poses significant challenges. This study introduces a novel method for synthesizing highly porous tin oxide (SnO2) nanostructures using carbon as the template material. The synthesis process includes the formation of a precursor composite containing resorcinol-formaldehyde gel and a tin oxide precursor, which is first carbonized to convert the resorcinol-formaldehyde into a porous three-dimensional carbon framework. This framework acts as a scaffold for the nucleation of SnO2 nanoparticles. Subsequent oxidation selectively removes the carbon template, yielding highly porous SnO2 nanomaterials. Electron microscopy analysis shows that the nanomaterials feature a particle size with average diameter of ∼30 nm, whereas Gas adsorption-desorption characterization indicates pronounced mesoporosity, with a pore size of 3 nm and a specific surface area of 476 m2/g. The enhanced surface area surpasses the previously reported studies on porous SnO2. This is significant considering the easy production process of the nanomaterials, which signifies its potential for large-scale production. Furthermore, this approach offers versatility, as different materials can replace the carbon component, allowing for tailored nanostructure design and enhanced properties. The resulting materials can offer exciting possibilities in the field of materials science and nanotechnology.

Hard carbon (HC) is a promising negative‐electrode material for Na‐ion batteries. HC electrochemically stores Na+ ions, resulting in a non‐stoichiometric chemical composition depending on their nanoscale structure, including the carbon framework, and interstitial pores. Therefore, optimizing these structures for Na storage by altering the synthesis conditions can enhance the capacity of Na‐ion batteries. In this study, HCs using MgO, ZnO, and CaCO3 as nanopore templates are systematically investigated, and the ZnO template is found to be particularly effective. By optimizing the concentration of ZnO embedded in the carbon matrix, utilizing a blend of zinc gluconate, and zinc acetate as starting materials, the optimal ZnO‐template HC demonstrates a reversible capacity of 464 mAh g−1 (corresponding to NaC4.8) with high initial coulombic efficiency of 91.7% and low average potential of 0.18 V versus Na+/Na. Thus, a Na‐ion battery full cell consisting of Na5/6Ni1/3Fe1/6Mn1/6Ti1/3O2 and the optimized ZnO‐template HC demonstrates a remarkable energy density of 312 Wh kg−1, comparable to that of a Li‐ion battery with LiFePO4 and graphite. Moreover, the ZnO‐template HC in a K half‐cell also displays a significant capacity of 381 mAh g−1, that is, KC5.8 where the alkali content is higher than stage‐1 graphite intercalation compounds, LiC6 and KC8. [ABSTRACT FROM AUTHOR]

Photocatalysis is a green technology with important application prospects in environmental fields such as wastewater treatment. Herein, we synthesized chrysanthemum‐like BiOBr microspheres (CLB0.45) by introduction of structure guide and soft‐template. Natural biomass chitosan (CS) in the precursor of BiOBr successfully suppressed the growth of both (001) and (102) lattice planes through the solvent effect, and promoted the exposure of (110) lattice planes that dominated the photocatalytic performance. Significantly, the polymer chains regulated the nanosheets of BiOBr to accurately self‐assemble. The obtained CLB0.45 had narrower band gap and more active sites due to surface defects, and the photocatalysts have higher photo‐electron hole pairs separation efficiency. Additionally, the degradation performance towards rhodamine B (RhB; 99.7 %, 30 min) of the CLB0.45 was increased, which was 4.6 times higher than that of pure BiOBr. The degradation rate of tetracycline (TC) was also excellent (85.3 %). The photodegradation mechanism of CLB0.45 was proposed and verified. In summary, the prepared CLB0.45, obtained through structure guiding and using a soft template, have a promising future in the photocatalytic purification of organic pollutants. [ABSTRACT FROM AUTHOR]

This article discusses the influence of the cell size of the initial template, solution concentration, and number of impregnation stages on the macrostructural and strength characteristics of glassy carbon foams produced by template synthesis. The Novolak resin SFP-012A2 was used as a carbon precursor; its coke residue is higher than 57 wt %. Increasing the number of impregnation stages makes it possible to improve the strength characteristics while maintaining open porosity at the level of 90%. The best set of properties is demonstrated by glassy carbon foam based on polyurethane template with a porosity of 60 pores/inch and four impregnation stages using a solution with a concentration of 30 wt % due to uniform wall thickening in the material. The ultimate compression strength is 1.12 MPa, which is two times higher than that of foreign analogs; the open porosity is 91%. A decrease in the cell size of initial templates can lead to embrittlement of the material due to the formation of clusters of overlapped cells. Increasing the mechanical strength of glassy carbon foams while maintaining an open-cell structure expands the range of applications for this class of materials. [ABSTRACT FROM AUTHOR]

In this work, an improved method of template synthesis including an additional post-carbonization stage has been developed. A sample of nanostructured carbonaceous material synthesized by this method was studied using low-temperature N2 ad(de)sorption and derivatography and compared with the conventionally synthesized sample and the activated anthracite sample. Also, the acidity of the materials by Boehm titration and the effect of Ni introduction on thermal characteristics of the samples were evaluated. In the post-carbonized sample, the development of the external surface and mesoporosity in the nanoscale range of 6–20 nm was observed as well as a reduction in the number of micropores. This had a positive effect on the thermal stability of the material, which was confirmed by the calculated values of the combustion activation energy. The post-carbonization stage promoted the formation of a phase whose thermal stability was close to that in activated anthracite. In terms of thermal stability, this phase was also less sensitive to the negative effect of the introduction of Ni compared to the phases of the conventionally synthesized sample. The existence of phases with different thermal stability in nanostructured carbonaceous materials was interpreted in terms of differences in the local concentration of activity centers in the material. An increased thermal stability of the additionally carbonized material was explained by a reduction of its microporosity and, ultimately, a decrease in the number of activity centers (surface defects, acid sites, etc.), which are the factors that initiate the carbon combustion. [ABSTRACT FROM AUTHOR]

Two methods for preparing mesoporous CeO2/Au nanocomposites were compared: template synthesis and photochemical modification of fibrous cerium(IV) oxide with gold nanoparticles. The composition, structure, and morphology, as well as the specific surface area and the pore size distribution of the obtained nanocomposites were studied by a set of physicochemical methods: X-ray phase analysis, energy dispersive X-ray microanalysis, scanning electron microscopy, low-temperature nitrogen adsorption, and electronic spectroscopy. The catalytic properties of the synthesized nanocomposites were evaluated in the methyl orange photodegradation reactions. It was shown that the CeO2/Au catalyst prepared by the photochemical modification method has the highest photocatalytic activity under exposure to both UV and visible light. [ABSTRACT FROM AUTHOR]

Fragile hemiaminal ether linkages present in the backbone of koneramines (LROR'), tridentate ligands, bound to copper(II) in stereoselectively self‐assembled syn‐[Cu(LROR')X2] complexes were transformed into sturdy methylene linkages to make corresponding rac‐[Cu(LRH)Cl2] complexes by late‐stage ligand modification after coordination with the retention of coordination sphere. The generality of stereoselective self‐assembly of koneramine complexes is shown by utilising a number of metal ions, anions, amines, alcohols and thiols with complete characterisations. [ABSTRACT FROM AUTHOR]

Nanostructured materials with high aspect ratios have been widely studied for their unique properties. In particular, nanosheets have safety, dispersibility, and nanosized effects, and nanosheets with exceptionally small thicknesses exhibit unique properties. For non‐exfoliable materials, the bottom‐up nanosheet growth using various interfaces as templates have been investigated. This review article presents the synthesis of nanosheets at the interfaces and layered structure; it explains the features of each interface type, its advantages, and its uniqueness. The interfaces work as templates for nanosheet synthesis. We can easily use the liquid‐liquid and gas‐liquid interfaces as the templates; however, the thickness of nanosheets usually becomes thick because it allows materials to grow in thickness. The solid‐gas and solid‐liquid interfaces can prevent nanosheets from growing in thickness. However, the removal of template solids is required after the synthesis. The layered structures of various materials provide two‐dimensional reaction fields between the layers. These methods have high versatility, and the nanosheets synthesized by these methods are thin. Finally, this review examines the key challenges and opportunities associated with scalable nanosheet synthesis methods for industrial production. [ABSTRACT FROM AUTHOR]

The use of nitrogen-doped carbon materials as electrodes in supercapacitors is a promising area of research. In this study highly-porous nitrogen-containing carbon materials were obtained by pyrolysis of melamine formaldehyde resin in the presence of nanocrystalline MgO as a hard template that was washed off after the pyrolysis. Magnesium citrate was used as a precursor for the synthesis of the template agent in situ during the pyrolysis of the resin. The obtained materials were characterized by X-ray diffraction, BET nitrogen adsorption method and Raman spectroscopy. The presence of nitrogen in the amount of 4 atomic percent was proved by XPS spectroscopy. The specific surface area was found to increase monotonically from 10 to 1300 m2/g with an increase in the content of magnesium citrate in the initial mixture. The samples showed high capacitance of 120 F/g in 1 M H2SO4 electrolyte and can be used in supercapacitors.

Since the development of the first method for porphyrin synthesis by Rothemund in 1935, porphyrin derivatives have been widely investigated and have played an essential role in chemical sciences. Most synthetic routes of porphyrins involve oxidative aromatization. Herein, we present a synthetic method to produce ABCD‐porphyrins, including chiral ones, through a one‐pot reaction involving "coordination, cyclization, and dehydrative aromatization" using a mono‐dipyrrinatoPt(II)Cl(COE) (COE=cyclooctene) complex as a platinum template. [ABSTRACT FROM AUTHOR]

Here, we propose a drug delivery system for ciprofloxacin (CF) based on cyclodextrin (CD) polymer. We obtained a 3D matrix system with encapsulated drug molecules by crosslinking CF+CD non-covalent complexes with 1.6-hexamethylene isocyanate. The obtained polycarbamide (MAX-system) represents particles (~225 nm in diameter) that demonstrate CF's sustained release. We investigated how the carrier affects the drug's interaction with the biological macromolecule human serum albumin (HSA) and CF's antibacterial properties. Compared to a binary CF–HSA system, CD decreases CF's binding efficiency to HSA by two times, whereas CF encapsulation in a polymer matrix doubles the Ka value and prevents protein aggregation. The changes in HSA's secondary structure indicate no alterations in the main mechanism of complex formation between CF and HSA in the presence of both CD-based carriers. CD as well as MAX systems practically do not change CF's activity against E. coli and B. subtilis, but for MAX systems, prolonged action is realized due to CF's sustained release. We believe that our findings are important for the further development of new, efficient drug forms. [ABSTRACT FROM AUTHOR]

Gallium (Ga) and aluminum (Al) belong to group IIIA elements in the periodic table. They show a coupled geochemical behavior in most natural systems and are considered as "geochemical partners." However, compared with the principal oxyhydroxides of Al in nature, gibbsite [Al(OH)3], boehmite (γ-AlOOH), and diaspore (α-AlOOH), only the analogs söhngeite [Ga(OH)3] and tsumgallite (α-GaOOH) were reported. In this work, boehmite-type GaOOH (γ-GaOOH), a new polymorph of GaOOH, was synthesized for the first time using boehmite (γ-AlOOH) as a template. The synthesized γ-GaOOH was characterized by a series of techniques, including X-ray diffraction (XRD), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and selected area electron diffraction (SAED). Furthermore, a model based on the boehmite structure was successfully applied to define the γ-GaOOH structure by the Rietveld method. Results from sample characterization and structural refinement support the successful synthesis of boehmite-type GaOOH, and thus it is referred to as γ-GaOOH. The synthesis of γ-GaOOH in the laboratory is valuable to understanding the Ga geochemistry and its enrichment process in Ga-rich boehmite in coal and bauxite. [ABSTRACT FROM AUTHOR]

Graphdiyne (GDY) is an exclusive carbon allotrope with a two‐dimensional (2D) structure that can be synthesized in laboratory settings. Due to its distinctive 2D structure and excellent electronic properties, GDY has captured the great interest of researchers. In addition, the porous nature and high specific surface area of GDY afford numerous storage sites and channels, rendering it highly promising for diverse applications. The synthesis of GDY still faces a multitude of obstacles and challenges. Developing new synthesis methods towards high‐quality GDY is particularly significant. As such, we here presented an overview of the reported synthesis techniques for GDY, categorizing them into three distinct approaches: interfacial synthesis, solid‐phase synthesis, and solution‐phase synthesis. This comprehensive summary provides valuable references for addressing the persistent challenges in the synthesis of GDY. In the end, an outlook sheds light on future research of the GDY materials. [ABSTRACT FROM AUTHOR]

Proximity‐induced chemical reactions are site‐specific and rapid by taking advantage of their high affinity and highly selective interactions with the template. However, reactions induced solely by antibody–antigen interactions have not been developed. Herein, we propose a biepitopic antigen‐templated chemical reaction (BATER) as a novel template reaction. In BATER, reactive functional groups are conjugated to two antibodies that interact with two epitopes of the same antigen to accelerate the reaction. We developed a method for visualizing the progress of BATER using fluorogenic click chemistry for optimal antibody selection and linker design. The reaction is accelerated in the presence of a specific antigen in a linker length‐dependent manner. The choice of the antibody epitope is important for a rapid reaction. This design will lead to various applications of BATER in living systems. [ABSTRACT FROM AUTHOR]

Nanofibers are fibers having nanometric diameters, made from a variety of polymeric materials, generally developed using electrospinning methods. It can incorporate multiple drugs, such as proteins, peptides, antibodies, and small molecules, either loaded inside or adhered to the surface. They offer enormous potential in the biomedical field, including drug delivery, regenerative medicine, stent coating, implants, and controlled drug release. The application of nanofibers in tissue regeneration have attracted a lot of interest due to their distinctive composition and structural characteristics. The application of nanofiber technology has also gained attention for wound healing, considering most conventional wound dressings have problems and drawbacks include infection, irritation, pain, and weak adhesive properties. This review highlights the major properties of nanofibers, their fabrication techniques, novel delivery approaches using electro spun technology for controlled drug release applications, and various other applications in the medical and healthcare field. The importance of Quality by Design (QbD) principles in the production of nanofibers, recent clinical trials conducted, patents filed in the field of nanofiber technology and various product developed by electrospinning technology were also discussed. [ABSTRACT FROM AUTHOR]

CeO2 nanooxide has been synthesized from cerium(III) nitrate using powdered cellulose (PC) and its mixture with sucrose as templates. The removal of templates from composites (PC–Ce(NO3)3 and PC–sucrose–Ce(NO3)3) has been carried out in two ways: via direct burning-out of PC (PC–sucrose) in an air flow and via burning-out of the carbonizate after template pyrolysis. Using UV and IR spectroscopy, X-ray powder diffraction (XRD), and electron microscopy, the influence of the template composition and the method of its removal on the physicochemical characteristics of CeO2 nanoparticles has been studied. A carbon–oxide material CeO2/C has been synthesized by pyrolysis of PC–Ce(NO3)3 and PC–sucrose–Ce(NO3)3 composites. It has been established that the pyrolysis of PC–Ce(NO3)3 and PC–sucrose–Ce(NO3)3 leads to the formation, in the carbonizate, of CeO2 (cerianite) nanoparticles with sizes of 3–4 and 1–2.5 nm, respectively. The average diameter of nanoparticles (according to XRD data) is 3.8 and 2.3 nm. CeO2/C synthesized from the PC–sucrose–Ce(NO3)3 composite contains cerium(III) oxide. All CeO2 nanoparticles in the carbon matrix have a hydroxyl–hydrate cover. The burning of the organic or carbon matrix of the composites leads, regardless of the template used and synthesis conditions, to the formation of CeO2 (cerianite) nanoparticles with the same average diameter of 25 ± 1 nm (according to XRD data), containing an admixture of the Ce(III) phase and having a hydroxyl–hydrate cover. Carbon is present in the material in trace amounts (≤0.15 wt %). The size scatter of CeO2 nanoparticles produced by burning out PC from the PC–Ce(NO3)3 composite is 15–30 nm. In those cases when the organic component from PC–sucrose–Ce(NO3)3 is subjected to burning or the pyrolysis stage of both composites is included in the synthesis process, the appearance of a fraction of larger CeO2 particles (50–60 nm) is observed. The correctness of the obtained data has been confirmed in the course of the model process of hydrogen peroxide decomposition. [ABSTRACT FROM AUTHOR]

Using density functional theory (DFT) B3PW91/TZVP, M06/TZVP, and OPBE/TZVP chemistry models and the Gaussian09 program, a quantum-chemical calculation of geometric and thermodynamic parameters of Ni(II), Cu(II), and Zn(II) macrotetracyclic chelates, with (NNNN)-coordination of ligand donor centers arising during template synthesis between the indicated ions of 3d elements, thiocarbohydrazide H2N–HN–C(=S)–NH–NH2 and diacetyl Me–C(=O)–C(=O)–Me, in gelatin-immobilized matrix implants was performed. The key bond lengths and bond angles in these coordination compounds are provided, and it is noted that in all these complexes the MN4 chelate sites, the grouping of N4 atoms bonded to the M atom, and the five-membered and six-membered metal chelate rings are practically coplanar. NBO analysis of these compounds was carried out, on the basis of which it was shown that all these complexes, in full accordance with theoretical expectations, are low-spin complexes. The standard thermodynamic characteristics of the template reactions for the formation of the above complexes are also presented. Good agreement between the data obtained using the above DFT levels is noted. [ABSTRACT FROM AUTHOR]

The binding of the terdentate precursor 2,2′‐(4‐methyl‐3,5‐divinylpyridine‐2,6‐diyl)bis(1‐allyl‐5‐bromo‐1H‐benzo[d]imidazole) (1) to the lanthanide container [Ln(hfac)3] (Ln=La, Eu, Gd, Y, Er; H‐hfac=1,1,1,5,5,5‐hexafluoropentane‐2,4‐dione) ensures the cis‐cis orientation of the two adjacent α,α′‐diimine units that is required for the successful intramolecular Grubb ring‐closing metathesis generating the target rigid 6‐methyl‐9,11‐dihydro‐1H,3H‐2λ2,10λ2‐pyrido[2,3‐c:6,5‐c′]bis(azepine) scaffold decorated with two terminal 5‐bromo‐1H‐benzo[d]imidazole in ligand L7. The bond valence analysis of the crystal structures of the associated nine‐coordinate adducts [L7Ln(hfac)3] (Ln=La, Eu, Gd, Er, Y) reveals a satisfying match between the rigid terdentate cavity and the size of the bound lanthanide metal, with a pronounced preference for the largest lanthanum cation. Thermodynamic studies in dichloromethane confirm the formation of [L7Ln(hfac)3] adducts with unprecedented stabilities due to the removal of the energy penalty associated with trans‐trans to cis‐cis reorganization. The introduction of saturated methylene groups within the polyaromatic ligand backbone breaks extended aromatic delocalization and clears the visible part of the electromagnetic spectrum from emission arising from low‐energy ligand‐based excited states. [ABSTRACT FROM AUTHOR]

2D ferroelectrics provide great promise for future electronics owing to their unique properties at 2D limit. Although simple perovskite oxides (such as BaTiO3 and PbTiO3) are an important target for 2D ferroelectrics, controlled synthesis of 2D nanosheets still remains a challenge. Here, this issue is addressed by using a new chemical protocol; unilamellar Ti0.87O2 nanosheets can serve as templates, guiding the solvothermal synthesis of 2D BaTiO3 nanosheets with a molecularly thin thickness (< 3 nm). Raman spectroscopy, second‐harmonic generation, and transmission electron microscopy characterizations suggest the formation of tetragonal ferroelectric BaTiO3 nanosheets. Based on piezoresponse force microscopy, BaTiO3 nanosheets exhibit a clear ferroelectric response with a high Curie temperature (≈100 °C) even down to 1.8 nm thickness. This study provides new opportunities to investigate perovskite ferroelectrics with the critical thickness. [ABSTRACT FROM AUTHOR]

Porous α-Fe2O3 hollow rods/reduced graphene oxide (α-Fe2O3 HR/RGO) composites with unique morphological characteristics and a high surface area are prepared through a template strategy, which was systematically studied and found to have outstanding supercapacitive properties. When served as active material in a three-electrode setup, the optimized α-Fe2O3 HR/RGO-30, comprised 76.5 wt% α-Fe2O3 and 23.2 wt% RGO, was able to offer the largest specific capacitance of 426.3 F g−1, an excellent rate capability as well as satisfactory cycle life with capacitance retention of 87.7% and Coulombic efficiency of 98.9% after continuously charging/discharging at 10 A g−1 for beyond 10,000 cycles. Such electrochemical behaviors of the α-Fe2O3 HR/RGO-30 electrode can rival or even surpass those of many Fe2O3-based electrodes documented in the previous literature. Later, a symmetric supercapacitor cell of α-Fe2O3 HR/RGO-30//α-Fe2O3 HR/RGO-30 was fabricated. The assembled device offers the maximum energy density of 18.7 Wh kg−1, and also exhibits commendable rate capability, and features stable cycling durability (with capacitance retention of 83.2% together with a Coulombic efficiency of 99.3% after 10,000-cycle charge/discharge at 5 A g−1). These notable electrochemical performances enable the α-Fe2O3 HR/RGO-30 composite to be a high-potential material for advanced energy storage systems.

Abstract 2D ferroelectrics provide great promise for future electronics owing to their unique properties at 2D limit. Although simple perovskite oxides (such as BaTiO3 and PbTiO3) are an important target for 2D ferroelectrics, controlled synthesis of 2D nanosheets still remains a challenge. Here, this issue is addressed by using a new chemical protocol; unilamellar Ti0.87O2 nanosheets can serve as templates, guiding the solvothermal synthesis of 2D BaTiO3 nanosheets with a molecularly thin thickness (< 3 nm). Raman spectroscopy, second‐harmonic generation, and transmission electron microscopy characterizations suggest the formation of tetragonal ferroelectric BaTiO3 nanosheets. Based on piezoresponse force microscopy, BaTiO3 nanosheets exhibit a clear ferroelectric response with a high Curie temperature (≈100 °C) even down to 1.8 nm thickness. This study provides new opportunities to investigate perovskite ferroelectrics with the critical thickness.

A method of template synthesis of nanocrystalline titanium(IV) oxide and its modification with gadolinium(III) and silver oxide nanoparticles have been developed. The composition and structure of the synthesized materials were characterized by X-ray phase analysis and IR spectroscopy. The specific surface area and pore size distribution were determined. The photocatalytic properties of the synthesized TiO2/Gd2O3 and TiO2/Gd2O3/Ag nanomaterials in the degradation reaction of methyl orange aqueous solutions upon irradiation with UV light were estimated. It was found that the introduction of gadolinium(III) oxide increases the photocatalytic activity of the material, and the introduction of silver particles makes the photocatalyst sensitive to light with a shorter wavelength. [ABSTRACT FROM AUTHOR]

In this work, the ability of several bis-viologen axles to thread a series of heteroditopic tris(N-phenylureido)calix[6]arene wheels to give interwoven supramolecular complexes to the [3]pseudorotaxane type was studied. The unidirectionality of the threading process inside these nonsymmetric wheels allows the formation of highly preorganised [3]pseudorotaxane and [3]rotaxane species in which the macrocycles phenylureido moieties, functionalised with either ester, carboxylic, or hydroxymethyl groups, are facing each other. As verified by NMR and semiempirical computational studies, these latter compounds possess the correct spatial arrangement of their subcomponents, which could lead, in principle, upon proper bridging reaction, to the realisation of upper-to-upper molecular capsules that are based on calix[6]arene derivatives. [ABSTRACT FROM AUTHOR]

Controllable in situ formation of nanoclusters with discrete active sites is highly desirable in heterogeneous catalysis. Herein, a titanium oxide-based Fenton-like catalyst is constructed using exfoliated Ti3C2 MXene as a template. Theoretical calculations reveal that a redox reaction between the surface Ti-deficit vacancies of the exfoliated Ti3C2 MXene and H2O2 molecules facilitates the in situ conversion of surface defects into titanium oxide nanoclusters anchoring on amorphous carbon (TiOx@C). The presence of mixed-valence Tid+ (d = 0, 2, 3, and 4) within TiOx@C is confirmed by X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) characterizations. The abundant surface defects within TiOx@C effectively promote the generation of reactive oxygen species (ROS) leading to superior and stable Fenton-like catalytic degradation of atrazine, a typical agricultural herbicide. Such an in situ construction of Fenton-like catalysts through defect engineering also applies to other MXene family materials, such as V2C and Nb2C. [ABSTRACT FROM AUTHOR]

A series of tin oxides were synthesized with polystyrene microspheres (250 nm) as the template. It was shown that an increase in the template content led to increasing specific pore volume and to the formation of bimodal pore structure with pores of 9 and 70 nm in diameter. Addition of cetyltrimethylammonium bromide (CTAB) during synthesis led to the formation of friable structures (SEM data), to an increase in the average pore diameter from 19 to 111 nm, and to the formation of macropores of 80–400 nm in size. All materials had similar surface properties and cassiterite structure with 5.9–10.8 nm coherent scattering region (XRD data). Flat-band potentials of the samples were determined and their photoelectrocatalytic properties to oxidation of water and methanol were studied in the potential range of 0.4–1.6 V RHE. It was shown that the sample obtained using CTAB was characterized by lower flat-band potential value, but appeared significantly higher photocurrent in methanol oxidation, which resulted from enhanced macro-meso-porous structure to facilitate methanol pore diffusion. [ABSTRACT FROM AUTHOR]

The increasing use of wind and solar energy creates an enormous need for intermittent storage of electrical energy in batteries [...]

We propose a facile template strategy for fabrication of porous δ manganese dioxide (δ-MnO2) hollow rods under mild conditions. First, highly dispersible molybdenum oxide (MoO3) rods were hydrothermally prepared. Next, MoO3/carbon (MoO3/C) composite rods were further synthesized by wrapping a MoO3 substrate with a polypyrrole thin layer through the oxidative polymerization of pyrrole, followed by annealing in an inert atmosphere. Finally, porous δ-MnO2 hollow rods were produced by redox reaction between the carbon component of MoO3/C and potassium permanganate (KMnO4), followed by total dissolution of MoO3 template. Such developed δ-MnO2 hollow rods were systematically characterized and found to show impressive electrochemical properties with the maximum specific capacitance of 171.3 F g−1, satisfactory rate performance and exceptional cycle stability with capacitance retention as high as 90.5% even after repetitively charging/discharging for over 10,000 cycles. The remarkable supercapacitive behavior of porous δ-MnO2 hollow rods surpass those of many MnO2-based electrode materials, thus featuring the potential for development of advanced energy storage devices. [ABSTRACT FROM AUTHOR]