Room Temperature Synthesis Research Articles

Lights on the Synthesis of Surfactant-Free Colloidal Gold Nanoparticles in Alkaline Mixtures of Alcohols and Water.

Surfactant-free colloidal syntheses in aqueous media are attractive to develop nanomaterials relevant for various applications, e. g. catalysis or medicine. However, controlled green syntheses without surfactants of metal nanoparticles in aqueous media remain scarce. Here, room temperature syntheses of gold (Au) nanoparticles (NPs) that require only HAuCl4, alkaline water and an alcohol, i. e. relatively benign chemicals and mild reaction conditions, are developed. The findings of a comprehensive multi-parameters screening performed in small volumes (<3 mL) over 1000+ experiments pave the way to greener high throughput screenings of large parametric spaces and lead to scalable (100 mL) synthetic strategies. A rational selection of the alcohol is proposed. The influence of lights with defined wavelengths (222-690 nm) is investigated. It is found that lights with lower wavelengths favor the formation of smaller 5 nm NPs. Different kinetics and formation pathways are observed for different alcohols and for lights with different wavelengths. The sensitivity to various experimental parameters increases with the alcohol used in the order glycerol<ethylene glycol<ethanol<methanol. New strategies for a rational fine size control, and to some extend shape control, are identified. The results lead to more sustainable and reproducible surfactant-free colloidal syntheses of NPs.

Room-Temperature Synthesis of a Fluorine-Functionalized Nanoporous Organic Polymer for Highly Efficient SF6 Adsorption and Separation.

Sulfur hexafluoride (SF6) is widely used in the power industry and significantly contributes to the greenhouse effect, necessitating the development of efficient materials for SF6 capture, particularly fluorine-containing materials. However, existing fluorine-containing materials often require complex monomers and high synthesis temperatures. Herein, we report the synthesis of a fluorine-functionalized carbazole-based nanoporous organic polymer (CNOP-7) at room temperature, using commercially available 4,4'-bis(9H-carbazole-9-yl)-1,1'-biphenyl and 1,1,1-trifluoroacetone. CNOP-7 contains 14.7% fluorine atoms and exhibits a high specific surface area of 1270 m2·g-1, demonstrating excellent SF6 adsorption and separation performance. The SF6/N2 selectivity of CNOP-7 reaches 107 at 273 K and 73 at 298 K. Furthermore, dynamic breakthrough experiments confirm that CNOP-7 can efficiently and repeatedly separate SF6 from SF6/N2 mixtures. Molecular simulations reveal the mechanism behind its efficient separation. This work offers fresh perspectives on the development and fabrication of adsorbents for efficient SF6 sequestration.

Room temperature in situ growth of fluorinated covalent organic framework on electrospun nanofibers for efficient detection of benzoylurea insecticide residue in water samples

The accurate detection of benzoylurea insecticides (BUs) residues is vital for the environment and human health. In this work, a room-temperature synthesis strategy was developed to fabricate the covalent organic framework (COF)–polyacrylonitrile (PAN) nanofibers composite by an electrospinning technique. The COF was functionalized on PAN nanofibers via in situ polymerization of 1,3,5-tris(4-aminophenyl)triazine (TAPT) and 2,3,5,6-tetrafluoroterephthaldehyde (TFTA). The obtained TAPT-TFTA@PAN nanofibers showed a porous structure, high surface area, good crystallinity and excellent extraction efficiency to BUs. A sensitive method combining dispersive solid-phase extraction (DSPE) using TAPT-TFTA@PAN nanofibers as an adsorbent with liquid chromatography–ultraviolet detector was developed for trace analysis of four BUs in environment water samples. This method achieved a wide linear range of 0.5–200 ng·mL−1 for triflumuron and hexaflumuron, and of 0.5–150 ng·mL−1 for teflubenzuron and fluazuron. The limits of detection (S/N = 3) for four BUs ranged from 0.11 to 0.42 ng·mL−1. The accuracy of the proposed method was validated by measuring trace BUs in the spiked water samples with recoveries in the range of 98.3 %∼125.3 %. The results demonstrated that the TAPT-TFTA@PAN nanofibers have great potential as an extractant for effective enrichment of benzoylurea insecticide from complex water samples.

Room-Temperature Single-Phase Synthesis of Semiconducting Metal-Covalent Organic Frameworks With Microenvironment-Tuned Photocatalytic Efficiency.

In order to improve the solubility of metallated monomers and product crystallinity, metal-covalent organic frameworks (MCOFs) are commonly prepared via high-temperature sol-vothermal synthesis. However, it hampers the direct extraction of crystallization evolution information. Exploring facile room-temperature strategies for both synthesizing MCOFs and exploiting the crystallinity mechanism is extremely desired. Herein, by a novel single-phase synthetic strategy, three MCOFs with different microstructure is rapidly prepared based on the Schiff base reaction between planarity-tunable C3v monomers and metallated monomers at room temperature. Based on detailed time-dependent experiments and theoretical calculations, it is found that there is a planarity-tuned and competitive growth relationship between disordered structures and crystal nucleus for the first time. The high planarity of monomers boosts the formation of crystal nucleus and rapid growth, suppressing the forming of amorphous structures. In addition, the microenvironment effect on selective photocatalytic coupling of benzylamine (BA) is investigated. The strong donor-acceptor (D-A) MCOF exhibits efficient photocatalytic activity with a high conversion rate of 99% and high selectivity of 99% in 5h under the 520nm light irradiation. This work opens a new pathway to scalable and efficient synthesis of highly crystalline MCOFs.

Ultrafast Room-Temperature Synthesis of Phosphate-Intercalated NiFe Layered Double Hydroxides for High-Performance Alkaline Seawater Oxidation.

Quick and easy synthetic methods and highly efficient catalytic performance are equally important to anodic oxygen evolution reaction (OER) electrocatalysts for alkaline seawater electrolysis. Herein, we report a facile one-step route to in situ growing PO43- intercalated NiFe layered double hydroxides (NiFe-LDH) on Ni foam (denoted as NiFe-P/NF) by a room-temperature immersion for several minutes. This ultrafast approach transforms the NF surface into a rough PO43- intercalated NiFe-LDH overlayer, which demonstrates outstanding OER performance in both alkaline simulated and natural seawaters owing to good hydrophilic interface and the electrostatic repulsion of PO43- against Cl- anions. Density functional theory calculations reveal that the intercalated PO43- can not only promote electron transfer but also prevent Cl- from entering the interlayer and simultaneously inhibit the migration of Cl- over the NiFe-LDH surface. In alkaline simulated and natural seawater electrolytes, NiFe-P/NF needs low overpotentials of 248 and 298 mV to achieve a current density of 100 mA cm-2, respectively. NiFe-P/NF can stably run over 42 h in an alkaline high-salty electrolyte (1 M KOH + 2.5 M NaCl) at 250 mA cm-2, more than 70 times that of NiFe/NF (0.6 h), emphasizing the critical role of the intercalated PO43- anions on the excellent durability. This study offers a new strategy to modify commercial NF to prepare efficient and stable OER catalysts for seawater electrolysis.

Streamlining Thionyl Tetrafluoride (SOF4) and Pentafluorooxosulfate [OSF5]- Anions Syntheses.

A one pot room temperature synthesis of thionyl tetrafluoride (SOF4) from elemental fluorine (F2) and thionyl fluoride (SOF2) is reported. The selective decagram scale process (100 mmol) allows a quantitative preparation of SOF4 with high purity. The solid-state structure has also been elucidated and compared with the reported gas-phase one. The use of this reagent for the formation of the emerging pentafluorooxosulfate [cat][OSF5] anions led to the preparation of multiple ion-pairs (cat = Ag, NEt3Me, PPN, PPh4) in different organic solvents. The SuFEx reservoir ability of this anion was studied and by tuning the solvent system, the reactivity of pure thionyl tetrafluoride was observed using Ag[OSF5] in THF and acetone.

Multifunctional and Hierarchical Porous ZIF-8: Amine and Thiol Tagged via Mixed Multivariate Ligand Strategies for Enhanced CO2 and Iodine Adsorption.

This study demonstrated a simple and innovative way of using the direct de novo synthesis to fabricate the mesoporous structure and diverse functionality of ZIF-8 for environmental cleanup and gas storage applications. By introducing different ligands, we have developed a version of ZIF-8 that could better capture carbon dioxide (CO2) and iodine. The ZIF-8 was successfully designed to have the hierarchical and mesoporous structure with the functional groups of amine and thiol groups by adjusting the pKa values (from 8 to 12) of ligand instead of original ligand, 2-methyl imidazole (Hmim, pKa~14.2). The modulation of ZIF-8 particle size, porosity, and functional characteristics was achieved through varied ligands and their concentrations, streamlined into a single and room-temperature synthesis condition. The resulting ZIF-8 materials exhibit intricate hierarchical architectures and a high density of functional groups, significantly enhancing molecular diffusion and accessibility. Among the developed materials, ZIF-8-AS, featuring both amine and thiol groups, demonstrates the fastest adsorption kinetics and a twofold increase in iodine adsorption capacity (qm = 1101.5 mg·g-1) compared to ZIF-8 (qm = 514.3 mg·g-1). Furthermore, the hierarchical mesoporosity of ZIF-8-A-10.1 improves CO2 adsorption to 1.0 mmol·g-1 at 298 K, which is 1.3 times higher than that of the microporous ZIF-8.

Adoption of self-exothermic reaction for synthesis of multifunctional carbon quantum dots: Applications to vincristine sensing and cell imaging

This work introduces an extremely easy method for preparing luminescent carbon dots (CDs) at ambient temperature using 1,2-naphthoquinone sulphonate and ethylenediamine as precursors via self-exothermic reaction without energy input. The as-obtained CDs have a high quantum yield (34.1 %), a production yield of 21.2 %, and a small size diameter (3.44 nm). Various techniques (NMR, TEM, EDX-mapping, XPS, XRD, FT-IR, fluorescence, and UV–visible spectroscopy) were used to characterize the prepared CDs. The CDs exhibited an excitation-independent emission with λex of 275 nm, demonstrating their homogeneity and high purity. The anticancer drug vincristine (VCR) quantitively quenched the fluorescent signal of the synthesized CDs, allowing their application as the first fluorescent nano-sensor to determine VCR. The quenching effect was linear within the range of 0.2–5.0 μg mL−1, enabling the determination of VCR in vials, plasma, and for content uniformity testing with a detection limit of 0.06 μg mL−1. Moreover, the synthesized CDs were employed as a bio-sensing platform to detect VCR in cancer cells owing to their good selectivity, excellent biocompatibility, minimal cytotoxicity, and high stability. The fabrication of CDs with excellent properties at room temperature under mild conditions paves the way for new advancements in the room temperature synthesis of CDs and offers a highly efficient alternative to traditional synthesis approaches.

Rapid room temperature synthesis of CuBi2O4 via ball-milling strategy boost light-driven persistent activation of hydrogen peroxide

Photo-Fenton technology with the superiorities of photocatalysis and traditional Fenton catalysis can improve the catalytic efficiency of photocatalytic materials and thus achieve efficient degradation for organic pollutants. However, exploring a low-cost catalyst with excellent catalytic performance using a simple method remains a challenge. In this work, CuBi2O4 photocatalyst synthesized by a mechanical ball-milling strategy (M-CuBi2O4) was exploited and used for tetracycline (TC) degradation. The impact of solution pH and H2O2 dosage on the photo-Fenton degradation efficiency of M-CuBi2O4 towards TC was investigated. M-CuBi2O4 exhibited significant 85.1% of photo-Fenton catalytic activity for TC removal, which was 9.35 times higher than that of CuBi2O4 synthesized by hydrothermal method (H-CuBi2O4). The enhanced catalytic performance of M-CuBi2O4 was due to the superior charge carrier separation efficiency, wider photo-response range and increased generation of active species. The primary active substances involved in the photo-Fenton reaction for TC degradation were determined to be hydroxyl radicals (•OH), superoxide radicals (•O2-), and singlet oxygen (1O2). This study provides a streamlined and rapid approach for macro preparation of high-performance photocatalysts for dealing with antibiotic-contaminated wastewater.

Room-Temperature Synthesis of Au@AuCu Alloyed Nanorods in Aqueous Solutions for High Catalytic Activity and Enhanced Stability

Room-Temperature Synthesis of Au@AuCu Alloyed Nanorods in Aqueous Solutions for High Catalytic Activity and Enhanced Stability

Room-temperature synthesis of covalent organic frameworks with dual functional groups for high-performance adsorption of diclofenac sodium from aqueous solution

Diclofenac sodium (DCF) are commonly found in ambient waterways due to its widespread use, and this poses significant risks to both human health and ecosystems. In this study, we have designed and synthesized a series of imine-linked covalent organic frameworks (COFs) with dual functional groups using a triple assembly strategy. Specifically, the platform molecules 2,5-dimethoxyterephthalaldehyde (DMTP), 2,5-dihydroxyterephthalaldehyde (DHTP), and 1,3,5-tris(4-aminophenyl)benzene (TAPB) were employed for the direct fabrication of COFs through Schiff base condensation reactions. As a proof of concept, three room-temperature synthesized COFs (COF TAPB-DMTP-[OH]n, where n represents the molar mass of DHTP, with n values of 0.02, 0.03, and 0.04) were used for DCF adsorption from water. The adsorption isotherms, kinetics, pH effects, ionic strength, co-existing ions, and COF regeneration for DCF were thoroughly investigated. The incorporation of methoxy (-OMe) and hydroxyl (-OH) groups serves as a functional strategy to facilitate hydrogen bonding interactions with DCF molecules. Consequently, the developed COFs, featuring an ultrahigh surface area and mesoporous structure, demonstrated a maximum adsorption capacity of 413.2 mg/g and a rate constant k2 of 0.0435 g/mg/min, which exceeds the performance of the majority of previously described adsorbents. The adsorption capacity toward DCF remained nearly unchanged after five regeneration cycles of the COF. Furthermore, the self-prepared adsorbent demonstrated efficient adsorption of DCF from real environmental water, indicating its potential for practical DCF removal applications.

Room Temperature Synthesis of Tellurium by Solution Atomic Layer Deposition.

This study demonstrates the deposition of tellurium (Te) on silicon/silicon nitride substrates using solution atomic layer deposition (sALD) at ambient temperature. The process employs tellurium tetrachloride (TeCl4) and bis(triethylsilyl)-telluride ((TES)2Te) as precursors, with toluene as the solvent. Growth parameters were optimized through systematic variation of the pulse and purge times. Morphological characterization via scanning and transmission electron microscopy revealed needle-like crystallites, while X-ray diffractometry confirmed the crystalline nature of the deposited Te. Increasing the number of deposition cycles resulted in larger Te crystallites and enhanced substrate surface coverage. A thin amorphous carbon shell surrounding the crystallites and carbon inclusions was observed, likely originating from the organic solvent. X-ray photoemission spectroscopy analysis indicated high-purity Te films with minimal surface oxidation. The small chlorine signal suggested a near-complete precursor reaction and the efficient purging of byproducts. This novel sALD approach presents a promising method for depositing Te on various surfaces under mild conditions.

Exploring the molarity of Lithium Fluoride in minimally intensive layer delamination (MILD) method for efficient room temperature synthesis of high quality Ti3C2Tx free-standing film

In recent years, MXene has become the most demanding material in the 2D family, leading to their increased use in research for a diverse range of applications, such as energy storage, water purification, optoelectronics, electromagnetic interference (EMI) shielding and medicine. However, recent research has made it increasingly important to synthesize high-quality MXene in a safe, reliable, fast, reproducible, and good-yielding single-step method. To achieve high-quality MXene by etching the MAX phase precursors, it is very important to critically optimize synthesis parameters, such as etching method, etchant concentrations, temperature, time, etc. Minimally intensive layer delamination (MILD) method for MXene synthesis using Lithium Fluoride (LiF) salt and hydrochloric (HCl) acid seems to be a better choice in the context of improved performance in different applications as well as its scalability and reproducibility. Here, the molar ratio of HCL/LIF is critical for Aluminium etching at room temperature to produce a high-quality MXene with = O, -OH, -F termination groups in the MILD method. However, in case of MILD method the effect of LiF/HCL concentrations on quality of MXene need to be addressed. In this study, we focus on room temperature etching of Ti3AlC2 using MILD method to synthesize quasi two-dimensional carbide (Ti3C2) MXene. The influence of molarity concentration of etchants (LiF and HCl) on quality of MXene has been thoroughly investigated. Different molar concentrations of Lithium Fluoride (LiF) with fixed HCL concentration were tested at room temperature for 24 h in the etching process. The crystal structure, microstructure and composition of the MXene were characterized using X-ray diffraction, Raman spectroscopy, and electron microscopy. Flexible free-standing MXene film with largest shift in the characteristic (002) peak, indicating large interplanar spacing, has been successfully achieved repeatedly for an optimum molar concentration of etchants at room temperature.

Room-temperature synthesis of carbon nano-onions by B4C sonication in water

Room-temperature synthesis of carbon nano-onions by B4C sonication in water

Room temperature synthesis of BaTiO3 nanoparticles using titanium bis(ammonium lactato) dihydroxide

BaTiO3, known for its exceptional ferroelectric properties, is extensively applied in multi-layer ceramics capacitors (MLCCs). Achieving reliable, high-performance MLCCs requires sophisticated ceramics processes, notably in synthesizing submicron-order BaTiO3 powder with a narrow size distribution. Among various synthesis methods explored for submicron-size BaTiO3 powder, room temperature liquid-phase synthesis is most desirable due to its cost-effectiveness and large batch availability. In this study, we propose a synthesis method for obtaining BaTiO3 nanopowder at room temperature using titanium bis(ammonium lactato) dihydroxide and Ba(OH)2·8H2O as starting materials, reacted in tert-butylamine with NaOH and ethanol. The resulting powder, exhibiting a cubic phase of BaTiO3 with an average particle size of 35.8 nm, was obtained after a 7-day reaction at room temperature. Characterization involved X-ray diffraction, differential thermal analysis‒thermogravimetry, and scanning electron microscopy. Subsequently, the powder was used to sinter a BaTiO3 ceramic, whose dielectric performance was then evaluated.

Facile room temperature synthesis of MIL-100(Fe) from magnetic zircon tailing and its application for methylene blue removal

Abstract Some of the dominant minerals found in the magnetic separation of zircon tailing are minerals containing iron (Fe). These materials have the potential to be processed into adsorbents. One of the materials synthesized using iron compounds as a precursor is MIL-100(Fe). The aim of this research was to obtain MIL-100(Fe) by utilizing magnetic zircon tailing, and applied as an adsorbent for methylene blue. The synthesis of MIL-100(Fe) was initiated by destruction of magnetic zircon tailing with HCl, followed by reacting the destruction filtrate with trimesic acid (H3BTC) for 24 hours at room temperature, in which the H3BTC was dissolved in NaOH with a molar ratio of 1.5 Fe : 1 H3BTC : 3 NaOH, prior to the reaction. A reddish orange precipitate obtained was then washed, dried, and characterized by using FTIR, XRD and SEM. Characteristics of FTIR spectra, XRD pattern and SEM images was similar with MIL-100(Fe) reported. The best-fitting model for the adsorption mechanism was the pseudo-second order. The most suitable adsorption isotherm was the Langmuir model. The maximum adsorption capacity of MIL-100(Fe)-W (222.89 mg/g) was higher than that of MIL-100(Fe)-C (151.59 mg/g). The result indicated that iron content in magnetic zircon tailing can be used as precursor for synthesis of MIL-100(Fe).

Room-temperature synthesis of carbon nano-onions by B&lt;sub&gt;4&lt;/sub&gt;C sonication in water

Room-temperature synthesis of carbon nano-onions by B&lt;sub&gt;4&lt;/sub&gt;C sonication in water

Room temperature synthesis of freestanding 2D Mn3O4 nanostructures with enriched electrochemical properties for supercapacitor application

Here we report low temperature growth of two dimensional freestanding nanoplatelets of manganese oxide (Mn3O4) through a simple and cost-effective wet chemical route without the utilization of capping agents. The pristine 2D Mn3O4 nanoplatelets have size and thickness between 100 and 200 nm and 3.5–5.1 nm respectively as corroborated by FESEM, TEM and AFM analysis. The electrochemical performance of the 2D Mn3O4 based electrode is studied using three electrode configuration and 1 M KOH as electrolyte where the remarkably high specific capacitance of 537 F/g (at 2 A g-1) is observed. Moreover, the 2D Mn3O4 based electrode is also found to exhibit an excellent retention of specific capacitance (∼ 93%) up to 5000 cycles. Thus enriched electrochemical performance of 2D Mn3O4 nanoplatelets reveals its potential as electrode material in supercapacitor device applications.

Room temperature synthesis of Ce based UiO-66 and UiO-66-NH2 metal organic frameworks for arsenic adsorption from aqueous solution

The exploration of a suitable adsorbent for removal of toxic elements is a challenging task and in this context we have employed UiO-66 (Ce) based Metal Organic Frameworks (MOFs) synthesized by a room temperature method for the remediation of arsenic from aqueous solutions. The synthesized UiO-66 (Ce) and UiO-66 (Ce)-NH2 MOFs were well characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), Thermogravimetry (TG), Brunauer–Emmett–Teller (B.E.T.), Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Octahedral morphology was observed for UiO-66 (Ce) whereas the morphology of UiO-66 (Ce)-NH2 synthesized by this method was non-uniform. Bare MOF exhibited higher surface area and higher thermal stability in contrast to the amine functionalized MOF. We have studied the arsenic adsorption on both these MOFs in varying pH conditions. The adsorption isotherm studies revealed that bare MOF is much superior for adsorption of arsenic with adsorption capacity of ∼308 mg/g whereas the adsorption capacity of amine functionalized MOF was mere 70 mg/g. Adsorption kinetic studies demonstrated that MOFs follow Pseudo Second Order (PSO) model and elucidated that the adsorption process is predominantly chemisorption in nature. UiO-66 (Ce) could be successively used multiple times without much penalty in the adsorption capacity and the thermodynamics of adsorption suggested it to be spontaneous and favorable. Finally, an overview of the probable mechanism of adsorption is discussed by employing different experimental techniques like XRD, FT-IR and XPS.

Rapid room-temperature synthesis of biocompatible metal–organic framework for enzyme immobilization with improved stability and on-demand release

Enzyme immobilization within metal–organic frameworks (MOFs) addresses the inherent fragility of enzymes, playing a crucial role across diverse industries by improving efficiency and lowering economic costs. While the application of MOFs in the food and pharmaceutical industries is constrained by toxicity concerns, MIL-88A(Fe) emerges as an ideal candidate due to its non-toxicity and biocompatibility. However, the release of encapsulated enzymes is significantly hampered, reducing their bioactivity. Herein, we present a safe and simple platform for creating enzyme@MIL-88A, which provides enzyme stabilization and controlled release. The thermal stabilization of a spectrum of enzymes (phytase, xylanase, amylase, mannanase, and glucanase) is achieved, elevating their endurance threshold to 95 °C. Furthermore, the controlled on-demand release of the encapsulated enzymes at target sites is accomplished by adjusting defects in enzyme@MIL-88A composites via an acid modulation approach, while preserving enzyme activity. This approach has improved the amount of enzyme released from 10 % to 99.7 %. To the best of our knowledge, this is the first time enzyme@MIL-88A has been synthesized rapidly under mild conditions for enzyme stabilization and controlled release. Our method offers a universal platform for stabilizing vulnerable biomaterials and the controlled delivery of biological macromolecules.