Facile Synthesis Research Articles

Six-channel colorimetric sensing of metal ions and advanced molecular information security based on fish scale-derived carbon–gold–silver nanocomposites

Due to its high flexibility and expansibility, nanomaterials-based systems have been constructed and applied from sensing, and medicine to molecular information technology. However, the current challenges include tedious and harsh nanomaterials preparation, the need for a wider range of response channels, new information paradigms, higher information density and length. Herein, fish-scale derived carbon nanomaterials (FSCN) were used as reducing and stabilizing agents for direct, green, and facile synthesis of carbon-bimetallic nanocomposites and applications in six-channel colorimetric sensing of Hg2+, and multi-combination and multi-round information encoding and protection for long text. First, the reaction sequence of three precursors (FSCN, Au3+, Ag+) was optimized to prepare FSCN–Au–Ag nanocomposites with double plasmonic absorption peaks of Au/Ag nanoparticles (NPs). The addition of Hg2+ causes the aggregation of nanoparticles and the formation of Ag/Hg amalgam or Au/Hg amalgam, FSCN–Au–Ag NPs were capable of multi-channel sensing (color, absorbance, and peak shift) of Hg2+. Especially, the detection limit of Hg2+ was 8.9 nM based on absorption response in wide wavelength range (456–546 nm), which was at least 6 times more sensitive than that at single wavelength. Moreover, different long text information can be encrypted and hidden in six-channel selective responses of FSCN–Au–Ag NPs-based colorimetric sensing system. By setting the threshold, these selective responses can be abstracted as a series of binary strings and then divided into shorter strings. Utilizing multi-combination and multi-round information coding, these short binary strings can be decrypted and merged into various long text content. This research promotes preparation and multi-purpose application of carbon-bimetallic nanomaterials, which provides new way to improve the sensing sensitivity of nanosystems and also offers new direction for molecular digitization.

Facile Synthesis of Sodium Alginate (SA)-Based Quaternary Bio-Nanocomposite (SA@Co-Zn-Ce) for Antioxidant Activity and Photocatalytic Degradation of Reactive Red 24

This study introduces a new strategy for the environmentally friendly catalytic degradation of Reactive Red 24 (RR24) dye using sunlight. We developed a cost-effective quaternary nanocomposite by immobilizing a sodium alginate biopolymer over bioengineered Co-Zn-Ce nanoparticles, forming an SA@Co–Zn–Ce nanocomposite (where SA means sodium alginate). This composite also demonstrated an exceptional antioxidant potential of approximately 89%, attributed to the synergistic effect of sodium alginate and green-synthesized Co–Zn–Ce nanoparticles (biosynthesized using Ocimum sanctum leaf extract as a reducing agent). Scanning electron microscopy revealed grain sizes of 28.6 nm for Co–Zn–Ce NPs and 25.59 nm for SA@Co–Zn–Ce nanocomposites (NCs). X-ray diffraction showed particle sizes of 16.87 nm and 15.43 nm, respectively. Co–Zn–Ce NPs exhibited a zeta potential of 1.99 mV, whereas the sodium alginate-anchored Co–Zn–Ce showed −7.99 mV. This indicated the entrapment of negatively charged ions from sodium alginate, altering the surface charge characteristics and enhancing the photocatalytic degradation of RR24. Dynamic light scattering revealed an average particle size of approximately 81 nm for SA@Co–Zn–Ce NCs, with the larger size due to the influence of water molecules in the colloidal solution affecting hydrodynamic diameter measurement. The SA@Co–Zn–Ce NCs exhibited a CO2 adsorption capacity of 3.29 mmol/g at 25 °C and 4.76 mmol/g at 40 °C, indicating temperature-dependent variations in adsorption capabilities. The specific surface area of Co–Zn–Ce oxide NPs, measured using Brunauer–Emmett–Teller (BET) analysis, was found to be 167.346 m2/g, whereas the SA@Co–Zn–Ce oxide nanocomposite showed a surface area of 24.14 m2/g. BJH analysis revealed average pore diameters of 34.60 Å for Co–Zn–Ce oxide NPs and 9.26 Å for SA@Co–Zn–Ce oxide NCs. Although the immobilization of sodium alginate on Co–Zn–Ce oxide NPs did not increase the adsorption sites and porosity of the composite, as evidenced by the N2 adsorption–desorption isotherms, the SA@Co–Zn–Ce oxide NCs still demonstrated a high photocatalytic degradation efficiency of RR24.

Facile green synthesis of Bi2S3 nanoparticles: Applications in simultaneous dye degradation and seed germination of fenugreek seeds

In this work, Bi2S3 nanoparticles (NPs) have been synthesized by the green combustion method at 500 °C for 10 min using C.argentae. The structure, optical, and morphological studies of the synthesized material were analysed using PXRD, FTIR, UV, PL, and SEM spectroscopy techniques. The PXRD pattern of the material demonstrates that the obtained particles are of bismuth sulphide with an orthorhombic structure. The FTIR spectrum of it shows a characteristic peak at 606.8 cm−1. In the UV–visible spectrum, on extrapolating the linear portion of the curve, the band gap on the X-axis is found to be 3.17 eV. PL intensity peaks show excitation and emission ranges of 384 nm and 532 nm respectively. SEM studies of the material show that the nanoparticles are in granular shape. Further, by using synthesized nanomaterials, photocatalytic degradation is carried out for methylene blue dye with different variations, and scavenger activity is carried out using K2Cr2O7, EDTA, ascorbic acid, and TBA. Seed germination activity is also carried out for fenugreek seeds with synthesized material and dye, with dye, and with a mixture of dye and nanoparticles, along with the simultaneous study of dye degradation.

A study on the facile synthesis of Cu-influenced organic framework and their characteristic properties

Today's nanomaterial scientific phases have been evolving through the most considerable novel MOF nano-characters. This study has described that the Cu (Copper) Nano-Metals based Metal-Organic Framework was synthesized by an affordable solvothermal method. With the facilitates of characterization methods, their factual physiochemical properties including Cu-MOF's crystalline characters, vibrational, surface morphology, surface chemical states, and obtained surface area have been examined. The X-ray diffraction–structural examination described the evident formation of metal oxide-coordinated MOF crystalline material. Before calcination, the MOF nanomaterial possessed an actual crystalline character of Cu-MOF with 22.3 nm of crystallite size then it became recrystallized after calcination. The co-contributions of Oxygen-linked organic molecular vibrational signatures upon Cu-O were analyzed through the Fourier Transform Infra-Red spectroscopy. Surface morphological magnifications exhibit plenty of pentagonal-shaped Cu-MOF nanomaterial with uniform distribution. Such a case also exhibits a flower-shaped Cu-MOF between pentagonal shapes with considerable surface porosity. X-ray photoelectron spectroscopy (XPS) has exhibited that the presence of oxygenated molecules contained copper oxide B.E states of synthesized Cu-MOF material. The UV–visible spectroscopy analysis has taken and the estimated bandgap of the Cu-MOF material is 2.3 eV. The thermal stability of the material has been analyzed through Thermo-Gravimetric analysis. To determine the internal structure of the Cu-MOF, an HR-TEM investigation was carried out. BET analysis exhibited 65.152 m2/g of active surface area. Due to the novel particle morphology with beneficial surface characteristics, the Cu-MOF possessed an efficient charge storage capacity of 383.3 Fg-1 due to its novel property.

Phyto-mediated facile synthesis of ZnO nanoparticles: enhanced photocatalysis, biological, and electrochemical properties

Phyto-mediated facile synthesis of ZnO nanoparticles: enhanced photocatalysis, biological, and electrochemical properties

Facile one-step solvothermal synthesis of Co3O4/CuO nanoflowers as an excellent catalyst for CO oxidation in coal mines

In the present study, Cobalt oxide (Co3O4)/Copper oxide (CuO) nanoflower catalysts were synthesized through a one-step solvothermal method, and the impact of various factors, including reaction time, on the catalytic activity of the catalysts towards carbon monoxide (CO) was investigated. The results showed that the catalysts synthesized at 140 °C and a reaction time of 4 h provided the best catalytic performance for carbon monoxide, and the regular nanoflower-like morphology provided a larger specific surface area as well as a greater number of active sites, allowing the instantaneous 100 % elimination of CO at 200 °C. Additionally, a plausible reaction mechanism was elucidated, wherein CO initially adsorbed onto the sample's surface, subsequently reacting with lattice oxygen to form intermediate carbonate species. This process ultimately led to the production of carbon dioxide (CO2), followed by the desorption of CO2 molecules from the sample's surface. The results demonstrate that these composite catalysts effectively mitigate CO levels during CO over limit in coal mines, thereby enhancing the safety of production personnel.

Synthesis of Heterocyclic Sulfonium Triflates by Cu-Catalyzed Selective Sarylation with Aryl(mesityl)iodonium Salts

Background: An efficient method for synthesizing cyclic arylsulfonium salts has been developed by selective aryl transfer to the sulfur atom from aryl(mesityl)iodonium triflates, a recyclable series of diaryliodonium salts. Methods: The utilization of sulfonium salts as valuable intermediates is well-established, as they exhibit high reactivity under conditions of heating or UV irradiation. However, their synthesis typically involves the reaction of diarysulfoxide with acid anhydride, which requires the oxidation of sulfur(II) to sulfoxide(IV) and thus limits the scope of synthesis. Hence, in this study, we employed recyclable mesityliodonium(III) salts and copper catalysis. Results: The method was used to synthesize cyclic arylsulfonium salts without the need for preoxidation of the sulfur atom, resulting in a facile and high-yield synthesis. Conclusion: The desired cyclic arylsulfonium salts were synthesized through selective transfer of the aryl group from mesityliodonium salts, demonstrating the effectiveness of the new approach.

Facile synthesis of β-trifluoromethyl thioethers via DBN-catalyzed hydrothiolation of a-trifluoromethyl styrenes with thiols.

A very simple and atom-economical method for the synthesis of vicinal trifluoromethyl thioethers via DBN-catalyzed hydrothiolation of α-trifluoromethyl styrenes with thiols was reported. The reaction proceeded smoothly under mild reaction conditions and provided the β-CF3-thioethers in moderate to good yields in an anti-Markovnikov manner.

Harnessing the Reactivity of ortho-Alkynylaldehydes: Silver Triflate Catalyzed Regioselective Synthesis of Phosphonylated Fluorescent Molecules

AbstractAn efficient approach for the facile synthesis of phosphonylated 1,3-dihydrofuro[3,4-b]quinolines and dihydrofuro[3,4-b]pyridines is developed. Reaction proceeds by the formation of new C–P and C–O bonds affording Z-selective phosphonylated products at room temperature. Diphenylphosphine oxides and dialkyl phosphites are explicitly incorporated into the carbonyl carbon of o-alkynylaldehydes in good to excellent yields. The reaction exhibits mild conditions, broad substrate scope, and the formation of three new bonds in the presence of a silver catalyst. The mechanistic studies revealed that the reaction proceeded via an ionic pathway in a 5-exo-dig manner to give Z-selective products, which was validated by X-ray crystallographic studies. Photophysical studies of selected compounds revealed the emission maxima in the range of 455 nm.

Biocompatible luminescent carbon dots embedded in crosslinked chitosan/gelatin for in vitro dopamine release

The present work elucidates the synthesis and properties of chitosan/gelatin/carbon dot nanocomposite. The synthesized carbon dots are incorporated into the chitosan-gelatin matrix in the ratio of 1:1. This ratio was chosen as it showed better release, anti-bacterial and antioxidant properties. The integration of carbon dots and dopamine into the chitosan-gelatin matrix was confirmed by XRD, UV, IR analysis and TEM micrographs. Toxicity studies of the composite were examined with the help of the IC-21 macrophage cell line. The release of the drug was tabulated in-vitro, and Korsmeyer - Peppas Case II transport release kinetics was observed over a period of 30 h in pH 7. After 30 h, 90 % of the encapsulated dopamine was released from the matrix. The addition of carbon dots enhances the controlled and extended release of the drug. The system is also tested for antibacterial and antioxidant properties. The highlight of this work is the facile synthesis and luminescent property of chitosan-derived carbon dots. The embryos and larvae of zebrafish were treated with the synthesized carbon dots, which provided them with an incubation period of 24 h. They were then observed under a fluorescent microscope with DAPI, FTIC and TRITC filters. Excitation-dependant emission, i.e., blue, green, and red emission, was seen in the sample when excited with UV, blue and green wavelengths, respectively. Its fluorescence properties help in its use as a tracer in monitoring the flow and movement of the drug-loaded composite.

Rational synthesis of core/shell heterostructured quantum dots for improved self-powered photodetection performance enabled by energy band engineering

Colloidal quantum dots (CQDs), especially core-shell QDs, have attracted dramatic interests as emerging materials in optoelectronic devices due to their size tuneable band-gap, high absorption coefficient, facile and low-cost synthesis routing, etc. However, the precise design of core/shell band engineering along with charge carrier transfer efficiency are still challenging, inevitably impacting the performance of optoelectronic devices. Herein, three different types of CdSe/CdS core-shell heterostructured QDs have been obtained via a proposed synthesis strategy of adjusting the core size but fixing the shell thickness. The performance of the core-shell QDs based self-powered photodetectors can be efficiently regulated by the optimization of synthesis strategy with the design of energy band alignment. Compared to the quasi type-II and the type-I QDs devices, the Ilight/Idark ratio of type-II heterostructure based photodetector is increased by ∼2 and ∼5 orders of magnitude, respectively. The champion device exhibits extraordinary optoelectronic performance in terms of ultrahigh light-to-dark current ratio of 105, photoresponsivity of 10.64 mA/W, at bias of 0 V, respectively. The charge carrier dynamics and transfer mechanisms of the QDs were further investigated, revealing the improved carrier separation and transportation efficiency induced by a strong build-in electric field in type-II CdSe/CdS core-shell heterostructure. This work provides a new strategy for the next-generation self-powered QDs optoelectronics enabled by the proposed synthesis approach along with the design of energy band alignment.

Facile synthesis of copper carbonate analog with peroxidase-like activity for colorimetric detection of isoniazid

In this article, copper carbonate analog with good peroxidase-like activity was successfully synthesized for the first time via a simple co-precipitation of CuSO4▪5H2O and Na2CO3. The obtained copper carbonate analog exhibited excellent intrinsic peroxidase-like activity towards a classical peroxidase substrate of 3, 3′, 5, 5′ -tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2) under an acidic environment. The study of the catalytic mechanism confirmed that the hydroxyl radical produced from the decomposition of H2O2 is the main reactive oxygen species responsible for the catalytic oxidation of TMB to oxTMB. Moreover, results from kinetic parameter analysis indicated that H2O2 was more easily and/or likely to attach to the copper carbonate analog than TMB. Subsequently, the effects of experimental conditions (buffer pH, temperature, and incubation time) on the catalytic activity of the copper carbonate analog were also optimized. Finally, a copper carbonate analog-based colorimetric sensor was developed to determine isoniazid. Under the optimal conditions, the linear range for isoniazid was as broad as 0–178.6 μM, and the detection limit was as low as 8.47 μM. The spiked recoveries of isoniazid in normal human serum has been observed in the range of 94.8%–105.5 %. This strategy focuses on the development of a green, cost-efficient peroxidase mimic with high activity, good biocompatibility, and a simple synthesis process.

Enhanced antimicrobial activity of photocatalytic titanium oxide upon formation of composites with polyaniline via an eco-friendly and facile microwave synthesis approach

This study proposes inexpensive antimicrobial polyaniline-titanium oxide (PANI-TiO2) samples prepared through eco-friendly enhanced microwave (MW) synthesis with 93 W applied over 10 min in aqueous 1.25 M hydrochloric acid media (HCl) using potassium iodate (KIO3) as oxidising agent, an approach suitable for industrial scale up production of PANI polymers at room temperature. The PANI-TiO2 samples are produced in the presence of 5–20 wt% of TiO2 in the initial reaction mixture along with aniline monomer by both the enhanced MW method and a classical chemical synthesis (CS) method at room temperature. The nanocomposites showed lower conductivity than pure PANI, slightly higher conductivity was observed in the MW prepared PANI-TiO2 in comparison to CS prepared PANI-TiO2. This result can be correlated with the observation that the optical absorbance of MW PANI-TiO2 samples were notable higher than for CS PANI-TiO2, which may be due to the presence of a greater amount of polarons present in the samples prepared by the enhanced MW method. MW PANI-TiO2 samples were equally active against both Gram-negative E. coli and Gram-positive S. aureus bacteria, in contrast to the CS PANI-TiO2 samples, which could be due to presence of short-chain fragments in the CS samples as confirmed by Fourier-transform infrared (FTIR) spectroscopy. The incorporation of PANI particles in TiO2 showed enhanced antimicrobial activity compared to pure TiO2, with greater antifungal activity. Our study indicates that a facile, low-cost, and green enhanced MW method can be used for preparation of the advanced antimicrobial PANI-TiO2 nanocomposites for biomedical applications.

In Situ Formation of an Artificial Lithium Oxalate-Rich Solid Electrolyte Interphase on 3D Ni Host for Highly Stable Lithium Metal Batteries.

Li metal, with a high theoretical capacity, is considered the most promising anode for next-generation high-energy-density batteries. However, the commercialization of the Li metal anode is limited owing to its high reactivity, significant volume expansion, continuous solid electrolyte interphase (SEI) layer degradation caused by undesirable Li deposition, and uncontrollable dendrite growth. This study demonstrates the in situ construction of a Li2C2O4-enriched SEI layer from NiC2O4 nanowires on three-dimensional Ni foam. The lithiophilic Li2C2O4-enriched SEI layer provides a uniform distribution of the electrical field and sufficient nucleation and deposition sites for Li without dendrite formation. Consequently, the stable Li2C2O4-enriched SEI layer successfully inhibits the formation of lithium dendrites, resulting in reversible Li stripping/plating behavior, maintained over an extended period of 5000 h with a deposition capacity of 1 mAh cm-2 at 1 mA cm-2. Additionally, a high cycling stability is observed in the full cell test with ∼70% capacity retention after 1300 cycles at 3 C. This approach offers a large-scale and facile synthesis process via the in situ precipitation growth of NiC2O4 followed by lithiation to form Li2C2O4. Furthermore, the significant stability of the Li2C2O4-enriched SEI layer aids the design of in situ-constructed SEI layers for highly stable Li metal batteries.

Self-Assembly of a Hierarchical Metal-Organic Framework at the Liquid/Liquid Interface via π-π Stacking Manipulations in Organoplatinum(IV) Complexes for Methanol Fuel Cells.

This study focuses on the facile synthesis of the hierarchical architecture of zeolitic imidazolate framework-8 (ZIF-8) films containing an ultrasmall amount of Pt(0) by investigating the synthesis of different organoplatinum complexes and manipulating the π-π stacking effect in these complexes at the liquid/liquid interface. The organometallic Pt(IV) precursors were complexes with a formula of [PtXMe2(R)(bpy)] (bpy = 2,2'-bipyridine; for complex 2, R = CH2CH═CHC6H5 and X = Br; for complex 3, R = CH2CH═CH2 and X = Br; for complex 4, R = Me and X = I) prepared by oxidative addition of cinnamyl bromide, allyl bromide, or methyl iodide to [PtMe2(bpy)] (complex 1). Different thin films were synthesized starting from three organometallic Pt(IV) precursors (i) by reduction of the Pt complexes at the toluene/water interface (TF2-TF4), (ii) by encapsulation of the Pt precursors in a ZIF-8 (TF5-TF7), and (iii) by reduction of the Pt precursors onto a ZIF-8 (TF8-TF10). The self-assembly of ZIF-8 and different organoplatinum precursors at the interface of two immiscible liquids leads to the preparation of films with well-engineered structures such as rhombic dodecahedra, nanorods, hierarchical architectures, and nanowires, which are very difficult and complicated to synthesize under normal conditions. The ultralow loading of platinum complexes with different degrees of π-π stacking of dangling moieties has a great impact on the structure and morphology (directing agent), which in turn drastically changes the catalytic properties. The obtained films were applied as electrocatalysts for methanol oxidation in fuel cells. The electrocatalytic performance of organoplatinum containing a cinnamyl group in hierarchical architecture TF8 was found to be superior to those of nonhierarchical structures.

Multicolor Tuning of Perylene Diimides Dyes for Targeted Organelle Imaging In Vivo.

The adjustment of the emission wavelengths and cell permeability of the perylene diimides (PDI) for multicolor cell imaging is a great challenge. Herein, based on a bay-region substituent engineering strategy, multicolor perylene diimides (MCPDI) were rationally designed and synthesized by introducing azetidine substituents on the bay region of PDIs. With the fine-tuned electron-donating ability of the azetidine substituents, these MCPDI showed high brightness, orange, red, and near infrared (NIR) fluorescence along with Stokes shifts increasing from 35 to 110 nm. Interestingly, azetidine substituents distorted to the plane of the MCPDI dyes, and the twist angle of monosubstituted MCPDI was larger than that of disubstituted MCPDI, which might efficiently decrease their π-π stacking. Moreover, all of these MCPDI dyes were cell-permeable and selectively stained various organelles for multicolor imaging of multiple organelles in living cells. Two-color imaging of lipid droplets (LDs) and other organelles stained with MCPDI dyes was performed to reveal the interaction between the LDs and other organelles in living cells. Furthermore, a NIR-emitting MCPDI dye with a mitochondria-targeted characteristic was successfully applied for tumor-specific imaging. The facile synthesis, excellent stability, high brightness, tunable fluorescence emission, and Stokes shifts make these MCPDI promising fluorescent probes for biological applications.

Facile and Green synthesis of Novel Fluorescent CQD’S from Calotropis Gigantea (blue) Leaves for Photocatalytic Degradation of Dyes

Facile and Green synthesis of Novel Fluorescent CQD’S from Calotropis Gigantea (blue) Leaves for Photocatalytic Degradation of Dyes

Efficient removal of Eosin Yellow dye using solvothermal synthesised Ni/Al layered double hydroxide and layered double oxide: insights into adsorption kinetics and thermodynamics

ABSTRACT The accumulation of organic pollutants in the environment is swelling steadily and raising the alarm for their redressal. Layered double hydroxides (LDH) and layered double oxides (LDO) are gaining prominence for their potential to address this challenge. This work includes an eco-friendly facile solvothermal synthesis of Ni/Al LDH and their calcination to Ni/Al LDO. The prepared nanomaterials were characterised by XRD, FE-SEM, HR-TEM, FT-IR, BET and TGA techniques, which confirm the highly porous structure of synthesised nanomaterials with a high specific area of 109.94 m2g−1 and 188.94 m2g−1 for Ni/Al LDH and Ni/Al LDO, respectively. A systematic study was conducted to explore the adsorptive potential of these materials towards the removal of organic dye Eosin Yellow (EY). The adsorptive efficiency was found to be 95% and 99% for Ni/Al LDH and Ni/Al LDO, respectively, under the optimised conditions of pH, adsorbent dose, contact time, dye concentration and temperature on adsorptive removal of EY dye, which was analysed by BBD-RSM (Box-Behnken Design Response surface methodology). The adsorption data fits best with the Freundlich isotherm model and pseudo-second-order kinetics. The thermodynamic study confirms the exothermic adsorptive process. The durability and reusability of the synthesised adsorbents were ascertained by their retention of the adsorptive efficiency even after five adsorption-desorption cycles which were as high as 91% and 85% for Ni/Al LDH and Ni/Al LDO, respectively. The mechanism of adsorption involves electrostatic interaction and hydrogen bonding between the surface of adsorbent and adsorbate as well as intercalation of dye molecules.

Facile synthesis of bimetallic metal–organic frameworks for highly efficient UV shielding

Facile synthesis of bimetallic metal–organic frameworks for highly efficient UV shielding

Facile synthesis, characterization, and in vitro biocompatibility of free‐standing titania hollow microtubes

Facile synthesis, characterization, and in vitro biocompatibility of free‐standing titania hollow microtubes