One-pot Microwave Synthesis Research Articles

Unlocking the potential of eggplant peel: Powerful peroxidase nanozyme for l-cysteine determination in pharmaceutical supplements

For the first time, eggplant peel biowaste was upcycled through a very fast one-pot microwave synthesis to produce cost-effective and environmentally friendly blue-fluorescent carbon dots (EPE-CDs). The resulting EPE-CDs emitted fluorescence at 465 nm when excited at 400 nm and exhibited enhanced peroxidase-like behavior without metal doping requirement. They were able to oxidize o-phenylenediamine (OPD) in the presence of hydrogen peroxide (H2O2) to generate 2,3-diaminophenazine (DAP) leading to a new emission peak at 560 nm. Through the inner filter effect, DAP was able to quench the fluorescence of EPE-CDs, causing a change from colourless to yellow. By leveraging the fluorescence characteristics of EPE-CDs and DAP, dual-emission platform was established. This platform could be used for the catalytic detection of H2O2 within the 10–110 μM range. The introduction of L-Cysteine, containing reductive thiols that hinder DAP production, resulted in a reduction in the fluorescence intensity of DAP. The study demonstrated that fluorescence intensities ratio 465 nm / 560 nm (I465/I560) exhibited a linear relationship with L-Cysteine concentration between 4 and 60 μM, reaching detection limit as low as 0.69 μM. Furthermore, when applying the ratiometric fluorescence platform to quantify L-Cysteine in actual samples, the average recoveries ranged from 99.50 % to 101.40 %, with a relative standard deviation (RSD) not exceeding 2 %. Through the exploration of the fluorescence properties and nanozyme-like capabilities, this research offers a novel perspective on utilizing biowaste sources for CD synthesis and utilization of these CDs as nanozymes.

One-pot Microwave Synthesis of Cobalt, Nitrogen, and Sulfur Co-Doped Carbon Quantum Dots for Efficient Monosodium Glutamate Determination in Food Samples

The synthesis of cobalt, nitrogen and sulfur co doped carbon quantum dots (Co-NS-CQDs) has become a subject of significant research interest. These CQDs were produced using a single-step microwave method, which is considered environmentally friendly, and the entire process was completed in just 90 seconds. In this synthesis, citric acid was utilized as the carbon source, methionine served as the source for both nitrogen and sulfur, and cobaltous acetate was used to introduce cobalt ions into the CQDs structure. The synthesized carbon quantum dots (CQDs) exhibit a narrow size distribution and a high quantum yield of 51.5%, which is notably superior to non-metal-doped CQDs with a yield of 38%. Characterization of these CQDs was performed using different techniques such as transmission electron microscopy (TEM), high-resolution TEM (HRTEM), Fourier transformation infrared spectroscopy (FTIR), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The developed CQDs have blue luminescence at emission wavelength 438 nm after excitation at 350 nm. Different factors affecting the CQDs synthesis including dialysis duration, reaction time and reaction temperature. These CQDs were utilized as a probe for the detection of monosodium glutamate (MSG) in various food products. The intensity of the fluorescence of the CQDs showed a direct and linear increase with the concentration of MSG within the range of 25–250 µg/mL. The detection and quantitation limits for MSG were 2.78 µg/mL and 8.44 µg/mL, respectively. Additionally, the developed method is environmentally friendly, as confirmed by assessments using the analytical Eco scale, Green Analytical Procedure Index (GAPI), and Analytical Greenness calculator (Agree). The proposed method presents several advantages over other reported methods in terms of convenience, rapid response, and attainment of accurate and precise results.

Humic Polyelectrolytes Facilitate Rapid Microwave Synthesis of Silver Nanoparticles Suitable for Wound-Healing Applications.

This article describes the one-pot microwave synthesis of silver nanoparticles (AgNPs) assisted with natural polyelectrolytes-humic substances (HS). The humic polyelectrolytes served both as chemical reductants for silver ions and as end-capping agents for AgNPs. Three commercially available sodium humates extracted from lignites and leonardite and one sodium fulvate isolated from natural brown water seeped through peat deposits were used in this study. The dynamics of the growth rate of AgNPs was characterised by UV-VIS spectroscopy by measuring the intensity of surface plasmon resonance at 420 nm. Transmission electron microscopy was used to characterise the size and morphology of AgNPs. Dynamic light scattering was used to determine size distributions of the synthesised AgNPs in the solutions. It was established that both conventional and microwave syntheses assisted with the coal humates produced small-size AgNPs in the range from 4 to 14 nm, with the maximum share of particles with sizes of (6 ± 2) nm by TEM estimates. The peat fulvate yielded much larger NPs with sizes from 10 to 50 nm by TEM estimates. DLS measurements revealed multimodal distributions of AgNPs stabilised with HS, which included both single NPs with the sizes from 5 to 15 nm, as well as their dominating aggregates with sizes from 20 to 200 nm and a smaller portion of extra-large aggregates up to 1000 nm. The given aggregates were loosely bound by humic polyelectrolyte, which prevented the coalescence of AgNPs into larger particles, as can be seen in the TEM images. The significant acceleration in the reaction time-a factor of 60 to 70-was achieved with the use of MW irradiation: from 240 min down to 210-240 s. The coal humate stabilised AgNPs showed antimicrobial properties in relation to S. aureus. A conclusion was made regarding the substantial advantages of microwave synthesis in the context of time and scaling up for the large-scale production of AgNP-HS preparations with antimicrobial properties suitable for external wound-healing applications.

A multifunctional nanocatalyst based on ultra-fluorescent carbon quantum dots for cascade enzymatic activity and stimuli-responsive chemotherapy of cancer

Clinical studies have switched from monotherapy to multimodal therapy due to the intricacy, multiplicity, and unpredictability of malignant tumors. In this work, we report one-pot microwave synthesis of highly fluorescent copper, nitrogen, and sulfur-doped carbon quantum dots (Cu,N,S-CQDs) with superior quantum yield (84%) and enhanced peroxidase-like activity. Then, Cu,N,S-CQDs was further biofunctionalized with glucose oxidase (GOx) and camptothecin (CPT) to form a multifunctional Cu,N,S-CQDs@GOx/CPT (CuCGC) nanocatalysts. The release of Cu2+ and S2− ions from CuCGC were promoted under acidic condition and catalyze the productions of hydroxyl (•OH) radical and H2S gas for chemodynamic (CDT) and gas (GT) therapy of cancer. Besides the CDT and GT effects, CuCGC also stimulates the breakdown of glucose into gluconic acid and peroxide solution for starvation therapy (ST) and ST-guided self-supplied CDT. CuCGC produce large quantities of reactive oxygen species (ROS) in the presence of H2O2 and glucose for enhanced cancer therapy via CDT and ST-guided CDT mechanisms. Interestingly, CuCGC nanocatalysts demonstrates ROS-responsive CPT release upon activation with H2O2 and glucose by CDT and ST-guided CDT, with about 66% of drug release was achieved in this study. In vitro analysis confirmed that our material reveals better biocompatibility towards cancer cells and caused substantial cell damage upon activation with H2O2and glucose through GT, CDT, ST, and chemotherapeutic mechanisms. Therefore, the designing of CuCGC nanocatalysts by coupling ROS-generator with stimuli-responsive drug was potential candidates in clinical studies.

One-pot microwave synthesis of chitosan-stabilized silver nanoparticles entrapped polyethylene oxide nanofibers, with their intrinsic antibacterial and antioxidant potency for wound healing

Different physical and chemical techniques could be used to prepare chitosan/Silver nanoparticle (CHS/AgNPs) nanocomposite. The microwave heating reactor was rationally adopted as a benign tool for preparing CHS/AgNPs owing to less energy consumption and shorter time required for completing the nucleation and growth particles. UV–Vis, FTIR, and XRD, provided conclusive evidence of the AgNPs creation, while TEM micrographs elucidated that the size was spherical (20 nm). CHS/AgNPs were embedded in polyethylene oxide (PEO) nanofiber via electrospinning, and their biological properties, cytotoxicity evaluation, antioxidant, and antibacterial activity assays were investigated. The generated nanofibers have mean diameters of 130.9 ± 9.5, 168.7 ± 18.8, and 186.8 ± 8.19 nm for PEO, PEO/ CHS, and PEO/ CHS (AgNPs), respectively. Because of the tiny AgNPs particle size loaded in PEO/CHS (AgNPs) fabricated nanofiber, good antibacterial activity with ZOI against E. coli was 51.2 ± 3.2, and S. aureus was 47.2 ± 2.1 for PEO/ CHS (AgNPs) nanofibers. Non-toxicity was observed against Human Skin Fibroblast and Keratinocytes cell lines (>93.5 %), which justifies its great antibacterial potential to remove or prevent infection in wounds with fewer adverse effects.

A rapid synthesis of molecularly imprinted polymer nanoparticles for the extraction of performance enhancing drugs (PIEDs).

It is becoming increasingly more significant to detect and separate hormones from water sources, with the development of synthetic recognition materials becoming an emerging field. The delicate nature of biological recognition materials such as the antibodies means the generation of robust viable synthetic alternatives has become a necessity. Molecularly imprinted nanoparticles (NanoMIPs) are an exciting class that has shown promise due the generation of high-affinity and specific materials. While nanoMIPs offer high affinity, robustness and reusability, their production can be tricky and laborious. Here we have developed a simple and rapid microwaveable suspension polymerisation technique to produce nanoMIPs for two related classes of drug targets, Selective Androgen Receptor Modulators (SARMs) and steroids. These nanoMIPs were produced using one-pot microwave synthesis with methacrylic acid (MAA) as the functional monomer and ethylene glycol dimethacrylate (EGDMA) as a suitable cross-linker, producing particles of an approximate range of 120-140 nm. With the SARMs-based nanoMIPs being able to rebind 94.08 and 94.46% of their target molecules (andarine, and RAD-140, respectively), while the steroidal-based nanoMIPs were able to rebind 96.62 and 96.80% of their target molecules (estradiol and testosterone, respectively). The affinity of nanoMIPs were investigated using Scatchard analysis, with Ka values of 6.60 × 106, 1.51 × 107, 1.04 × 107 and 1.51 × 107 M-1, for the binding of andarine, RAD-140, estradiol and testosterone, respectively. While the non-imprinted control polymer (NIP) shows a decrease in affinity with Ka values of 3.40 × 104, 1.01 × 104, 1.83 × 104, and 4.00 × 104 M-1, respectively. The nanoMIPs also demonstrated good selectivity and specificity of binding the targets from a complex matrix of river water, showing these functional materials offer multiple uses for trace compound analysis and/or sample clean-up.

Ethanolamine modified ordered mesoporous silica KIT-6: One-pot and rapid microwave synthesis, and efficient recovery for rhenium(VII)

Rhenium (Re) is a strategic key metal for the development of modernization and its efficient recovery from liquid sources plays an important role in the field of environment and energy. In this work, ethanolamine modified ordered mesoporous silica KIT-6 using Na2SiO3 as silicon source was prepared by one-pot and rapid microwave-assisted synthesis to recover Re(VII), which solved the long time-consuming synthesis problem of mesoporous silica materials by traditional methods. The acidity experiment showed that the optimal conditions for preparing ethanolamine modified ordered mesoporous silica KIT-6 (SS-C4M3–15-EA3-KIT-6) were microwave hydrothermal treatment for 3 h, glutaraldehyde (Glu) 15 mL, ethanolamine (EA), 3.0 g. FT-IR, XPS and functional density theory (DFT) analysis showed that chelation between the Schiff base (-CN-) and ReO4‾ together with electrostatic reaction gave it excellent adsorption performance, and its maximal adsorption capability was 111.41 mg·g−1. Moreover, ethanolamine modified ordered mesoporous silica KIT-6 had good regeneration performance and high selectivity for Re(VII) in mixed solution with Cu(II), Mn(II), Fe(III) and Zn(II). These findings suggested that the modified ordered mesoporous silica KIT-6 had a promising application in recovering Re(VII) from industrial wastewater.

Ion-/Thermo-Responsive fluorescent perylene-poly(ionic liquid) conjugates: One-pot microwave synthesis, self-aggregation and biological applications

This manuscript describes the attachment of alkylvinylimidazolium-based poly(ionic liquid) (PIL) to the imide positions of perylene bisimide (PBI) to introduce stimuli-responsiveness and to make the conjugate soluble in water and water-based mixed solvents with the possibilities of using them as a probe for imaging and diagnostics in biomedical domain. The alkylvinylimidazolium ionic liquid monomers (ILMs) are tailor-made and a one-step microwave-assisted method is employed for synthesizing the PBI-(Cys-PIL)2 conjugates by thiol-mediated radical polymerization of the ILMs using l-cysteine (Cys) with AIBN as initiator and in the presence of perylene-3,4,9,10-tetracarboxylic dianhydride (PDA). The introduction of PIL segment induces amphiphilicityto the conjugate, and it undergoes self-aggregation into vesicles in water and methanol/water mixture. Owing to the presence of PIL segments, the conjugates are responsive to anions forming insoluble spherical aggregates through the multipoint ionic crosslinking between the cationic PIL segments of neighbouring conjugate molecules in water and methanol/water mixture. The turbid color dispersion, containing spherical conjugate’s aggregates, shows upper critical solution temperature (UCST)-type phase transition to transparent solution upon heating. The variation of cloud point of conjugate could be done by changing different parameters such as molecular weight, nature of anions, and the length of the alkyl chain present in the PIL segment of the conjugate. The UV–vis and fluorescence spectra of the conjugate’s aggregates in solution change upon addition of anions. The monitoring of the spectral change upon heating due to disruption of aggregates allows us to determine the cloud point, which exactly matches with that obtain from turbidimetry. The water-soluble fluorescent PBI-(Cys-PIL)2 conjugate having cationic PIL segments shows low cytotoxicity and can be used in binding with ctDNA/plasmid DNA and imaging HeLa cells.

One-pot controlled microwave synthesis of Broadband-light absorbing irregular gold nanoparticles for solar cell application

Improvement of light-harvesting efficiency using the localized surface plasmon resonance (LSPR) from the metals nanoparticles (MNPs) is a promising approach to boost the efficiency of the solar energy conversion systems. To attain the narrowband SPR, synthesis of the monodisperse MNPs with particular shapes and sizes is cumbersome and has great importance for (surface-enhanced Raman spectroscopy) SERS application. Contrary, broadband SPR is prominent for solar cell applications to absorb maximum sunlight from the solar spectrum. Incorporating polydisperse MNPs of mixed shapes and sizes is a unique approach to realizing the broadband SPR for solar cell application. However, the synthesis of polydisperse MNPs with good reproducibility is challenging. To address this issue, we report facile one-pot microwave synthesis of mixed shapes and sizes of Au nanoparticles (Au-Mx), possessing broadband SPR with decent reproducibility. Microwave-assisted uniform heating provides the control over the reaction parameter to produce identical SPR. Further, the light-harvesting ability of the Au-Mx is demonstrated by incorporating ∼ 1% of Au-Mx in photoanode while fabricating the dye-sensitized solar cells (DSSCs). The photoconversion efficiency (PCE) of the Au-Mx loaded DSSCs improved by ∼ 30% compared to the reference devices, indicating the effective utilization of broadband SPR for efficient charge generation in plasmonic devices.

One-pot microwave synthesis of SnSe and Lanthanum doped SnSe nanostructure with direct Z scheme pattern for excellent photodegradation of organic pollutants

A novel nanostructure photocatalytic material was fabricated using Lanthanum doped SnSe by one-pot microwave method is reported to newest. Photocatalytic performance efficiency of pristine SnSe and Lanthanum doped SnSe nanostructures were investigated to degrade organic pollutants from wastewater. The crystal structure, morphology, and optical properties of the nanostructure were investigated using powder X-ray diffraction, field emission scanning electron microscope, UV–Vis, and PL spectral studies. Nano rods/spheres for pure SnSe were altered significantly leading to higher amounts of nanorods due to La doped and increase in concertation leads higher formation of nanorods. Increased in structure and morphology played a vital role in photocatalytic activity. Nanostructure exhibits enhanced physicochemical properties and showed an excellent synergetic effect demonstrating the effect of La (1, 3, and 5%) concentrations in SnSe nanostructure. The optical energy gap has a reducing trend due to the increment of doping concentration. The individual elements oxidation states were justified from X-ray photoelectron spectroscopical studies. Thermal stability and phase changes of the nanostructure before and after doping of La were evaluated through TGA/DTA analysis. From the photocatalytic measurement rare-earth (La) doped samples expressed higher catalytic nature than the pure SnSe. It was observed that the higher atomic element La had a significant role to produce a large number of electron-hole pair recombination and defective structure in the host lattice.

One-pot microwave synthesis of Pd modified titanium dioxide nanocrystals for 3D aerogel monoliths with efficient visible-light photocatalytic activity in a heated gas flow reactor

We present a one-pot microwave synthesis of Pd modified titanium dioxide nanocrystals for macroscopic aerogel monoliths, which are efficient visible-light photocatalysts for methanol oxidation in a heated gas flow reactor.

Microwave assisted formation of trimetallic AuPtCu nanoparticles from bimetallic nano-islands: Why it is a superior new age biocidal agent compared to monometallic & bimetallic nanoparticles

Due to rampant misuse of antibiotics, certain bacterial organisms have developed resistance against them as a result of genetic modifications, rendering a lot of the traditionally used antibiotics ineffective. Thus, introduction of a new class of antibacterial materials is paramount. This article reports exploring the comparative performances of monometallic Au, bimetallic AuPt and trimetallic AuPtCu as potential antibacterial agents for the future. The materials were obtained as nanofluids via a one-pot microwave synthesis procedure and subsequently were subjected to characterization by high-resolution electron microscopy, dynamic light scattering, X-ray diffraction, absorption spectroscopy and X-ray photoelectron spectroscopy, etc. It was found that the multimetallic particles were composed of several bimetallic alloy nano-islands and with increasing number of components the particle size became smaller and the microstructure became littered with defects. This had a profound effect on the antibacterial activity as the trimetallic AuPtCu was found to be the most effective against both the gram-negative and gram-positive bacterial strains. A detailed rationalization for the same has been provided based on the analysis of the structure-property-activity correlation. We anticipate the findings to be really important going forward; in the research and fabrication of new age medicines against drug-resistant micro-organisms.

Novel one-pot microwave synthesis of maleic anhydride based mineral scale inhibitors and their application

This paper presents our research efforts in the discovery of pioneering synthetic routes and designing low molecular-weight maleic-anhydride (MA) homopolymers and MA-n-octyl acrylamide (AAO) copolymers (YMR-series) and their application as scale inhibitors for mineral scales. Hence, the solvent-free, eco-friendly, rapid microwave-assisted method has been developed for the first time to synthesize these antiscalants with higher yield and better efficiency. The inhibition ability on the CaSO4 and CaCO3 scale is 100 % with a 3 ppm dosage level at pH 10.45 and temperature 70 °C.Morphological changes of the CaCO3 and CaSO4 scales due to the strong inhibition action of YMR-series polymers have been studied by scanning electronic microscopy (SEM) and X-ray powder diffraction (XRD) analysis. It is also observed that the anti-scaling effect of the polymers greatly depends on the molecular weight, while MA copolymers show better inhibition efficiency compared to MA homopolymers.

Silver-miang nanocomposites: A green, rapid and simple approach for selective determination of nitrite in water and meat samples

A green, rapid, simple and reliable procedure was developed for nitrite determination using silver-miang nanocomposites as colorimetric agents and camera phone as a detector. The crude water extracts of miang (Camellia sinensis var. assamica) were adopted as natural reagents in a rapid one-pot microwave synthesis of the nanocomposites. The extracts’ phytochemical contents were studied and the synthesis conditions were optimized. The yielded nanocomposites were characterized by UV–vis and FT-IR spectroscopies, powder X-ray diffraction, transmission electron microscopy, selected area electron diffraction and thermogravimetry, and proved to be reliable colorimetric agents and selective for nitrite. The underlying reactions were investigated. The linear calibration plots could be established based on the ratiometric R/G parameters over 2.0–10 mg∙L−1 nitrite concentration range with satisfying detection limits (0.12–0.62 mg∙L−1). In practice, the procedure was validated and applied with water and commercialized meat samples. The long storage time of miang (>5 years) was also evaluated, manifesting viability and reliability in views of both the nanocomposites synthesis and the nitrite determination performance.

One-pot microwave synthesis of hierarchical C-doped CuO dandelions/g-C3N4 nanocomposite with enhanced photostability for photoelectrochemical water splitting

Cupric oxide (CuO) is a semiconductor of choice for photocathode in photoelectrochemical (PEC) applications due to its great sunlight absorption capability. However, photocorrosion is the main drawback of CuO. Herein, CuO/graphitic carbon nitride (g-C3N4) with a unique microstructure, enhanced PEC performance, and considerable photostability is synthesized under microwave irradiation. A facile, one-pot method is utilized to directly deposit the nanocomposite onto fluorine-doped tin oxide from a solution containing copper precursor and urea. Possible mechanism of CuO/g-C3N4 formation through this novel method is investigated. It is elucidated that controlled amounts of urea critically determine the morphological evolution of CuO, while its excess quantities convert to g-C3N4 in the presence of CuO as the catalyst. Through an appropriate heat treatment, carbon is doped into CuO lattice. The obtained C-doped CuO/g-C3N4 demonstrates 227% enhancement over CuO in photocurrent density and ~80% photocurrent retention. The enhanced photoelectrocatalytic activity is mainly attributed to unique morphology of CuO, effective separation of charge carriers, and formation of heterojunction. These characteristics manifest the superiority of this approach over many other chemical-based methods. The nanocomposite synergistically integrates the advantages of both the constituents, offering a low-cost, efficient photocathode for PEC water splitting, photocatalytic hydrogen evolution, and degradation of pollutants.

Microwave-assisted rapid synthesis of C@Fe3O4 composite for removal of microplastics from drinking water

Filtration is a basic requirement for the production of clean drinking water. However, filtering of large-scale drinking water is a time-consuming and costly process. Addressed herein is a new approach to the removal of microplastics, defined as dangerous organic pollutants, from water. As magnetic adsorbent, highly porous and well dispersed C@Fe3O4 composites were produced by a facile and rapid one-pot microwave synthesis method in minutes. The prepared C@Fe3O4 composites were used as an adsorbent in water contaminated with microplastics. The obtained results revealed that the microplastics adhered to the composite surface and were successfully removed from the water with an external magnet. In this point, this study provides a new approach to the rapid, effective, and low-cost removal of microplastic pollutants from drinking water.

Uniform, Scalable, High-Temperature Microwave Shock for Nanoparticle Synthesis through Defect Engineering

Summary Here we demonstrate a thermal shock synthesis method triggered by microwave irradiation for the rapid synthesis of nanoparticles on reduced graphene oxide (RGO) substrate. With properly controlled reduction, RGO has high electrical conductivity while maintaining functional groups, leading to an extremely efficient microwave absorption of ∼70%. The high utilization of microwaves results in the ability to raise the temperature to 1,600 K in just 100 ms, which is followed by rapid quenching to room temperature. The defects on the RGO are crucial for achieving this record-high microwave-induced temperature as these defects play a fundamental role in absorbing the radiation as well as the self-quenching mechanism. By loading precursors onto RGO, we can utilize rapid temperature change to synthesize nanoparticles. The nanoparticles are ∼10 nm with uniform distribution. This facile, rapid, and universal synthesis technique has the potential to be employed in large-scale production of nanomaterials and suggests a new direction for nanosynthesis.

Microwave synthesised Pd-TiO2 for photocatalytic ammonia production.

Palladium doped anatase TiO2 nanoparticles were synthesised by a rapid (3 min) one-pot microwave synthesis technique at low temperature and pressure. After being fully characterised by SEM, XRD, Raman, XPS and EDX, photocatalytic nitrate reduction and ammonia production were studied over various dopant levels between 0–3.97 wt% Pd and compared to similar previous literature. Improved yields of ammonia were observed with most dopant levels when compared to non-doped microwave synthesised TiO2 with 2.65 wt% found to be the optimum dopant level producing 21.2 μmol NH3. Electrochemical impedance spectroscopy of TiO2 and Pd–TiO2 photoelectrodes revealed improvements in charge transfer characteristics at high Pd dopant levels.

Rapid One-Pot Microwave Synthesis of Mixed-Linker Hybrid Zeolitic-Imidazolate Framework Membranes for Tunable Gas Separations

The relatively slow and complex fabrication processes of polycrystalline metal-organic framework (MOF) membranes often times restrict their way to commercialization, despite their potential for molecular separation applications. Herein, we report a rapid one-pot microwave synthesis of mixed-linker hybrid zeolitic-imidazolate framework (ZIF) membranes consisting of 2-methylimidazolate (ZIF-8 linker) and benzimidazolate (ZIF-7 linker) linkers, termed ZIF-7-8 membranes. The fast-volumetric microwave heating in conjunction with a unique counter diffusion of metal and linker solutions enabled unprecedented rapid synthesis of well-intergrown ZIF-7-8 membranes in ∼90 s, the fastest MOF membrane preparation up to date. Furthermore, we were able to tune the molecular sieving properties of the ZIF-7-8 membranes by varying the benzimidazole-to-2-methylimidazole (bIm-to-mIm) linker ratio in the hybrid frameworks. The tuning of their molecular sieving properties led to the systematic change in the permeance and selectivity of various small gases. The unprecedented rapid synthesis of well-intergrown ZIF-7-8 membranes with tunable molecular sieving properties is an important step forward for the commercial gas separation applications of ZIF membranes.

One-pot Microwave Synthesis and Effect of Cu2+ ions on Structural Properties of Cu-ZnO Nano Crystals

The present study proposes that ion implementation and annealing temperature could be an effective approach for developing visible-light driven composite materials for solar cells. The present work outlines the synthesis of ZnO and Cu doped ZnOnanoparticles ranging from 0.8-5% via microwave combustion method without using any fuel. The ion implementation and the crystal structural analysis were characterized by X-ray diffraction (XRD). The shift of XRD peaks indicate Cuions incorporated into the ZnO lattice. These results have shown that the change in lattice parameters, d-spacing, unit cell volume and crystal sizes as the ion implementation occurs within the ZnO crystal, due to change in Cu concentration and annealing temperature, which leads to the improvement in the crystalline nature of the sample. Due to the Cu2+ ion diffusion into the ZnO lattice, it was found to be change in crystal defects leads to abrupt change in bond length and lattice strain