Molar Ratio Research Articles

Aqueous phase transfer of near-infrared ZnCuInS2/ZnS quantum dots: Synthesis and characterization

Cadmium-free and NIR fluorescent QDs are promising candidates for bio-application. Thus, we present the synthesis of ternary ZnCuInS2/ZnS (ZCIS/ZnS) quantum dots (QDs) where the molar variation of Cu/Zn of the precursors was used to tune the optical and structural properties. QDs with Cu/Zn molar ratio of 2/1 passivated with ZnS exhibited the best optical properties. They showed dominant near-infrared photoluminescence (approx. 850 nm) and highest quantum yield (approx. 52 %, λexc = 500 nm). Therefore, they were further subject to modification to ensure their transfer to the aqueous phase and improve biocompatibility. For this, different functionalization approaches were used. The first method relied on encapsulation with polymers like PSMA (poly(styrene co-maleic anhydride)) and PMAO (poly(maleic anhydride-alt-1-octadecene) coupled with polyetheramine (JEFF; Jeffamine M-1000), and the second relied on hydrophilization with PMAO. Furthermore, we also applied a surface ligand exchange process using DHLA (dihydrolipoic acid) and polyethylene glycol (PEG)-appended DHLA. The comprehensive study indicated that ZnCuInS2/ZnS QDs functionalized with PMAO (ZnCuInS2/ZnS@PMO) exhibited the highest photoluminescence (PL QY) along with ensured high colloidal stability in aqueous media. Moreover, no noticeable deterioration of the photoluminescence profile was observed for all used functionalization approaches. However, a significant decrease in QY was observed for almost all functionalized QDs except those that were PMO-capped. The synthesized QDs were systematically characterized by transmission electron microscopy (TEM), powder X-ray diffraction (XRD), UV–Vis absorption spectroscopy, and fluorescence spectroscopy. Biological studies indicate that the obtained hydrophilic ZCIS QDs are biocompatible and localized intracellularly inside endosomes.

Enzymatic interesterification of perilla seed oil and palm stearin: A sustainable approach to develop a novel zero-trans-fat margarine rich in omega-3 fatty acids.

The study focuses on developing a novel perilla seed oil (PeO)-based polyunsaturated fatty acid-rich margarine fat analogue using enzymatic interesterification. PeO is a rich source of omega-3 fatty acids, however, has limited application due to susceptibility to oxidative and thermal degradation. Moreover, low consumption of omega-3 fatty acids in modern diets serves as a major cause for increased prevalence of cardiovascular diseases. The stability of such oils can be improved by techniques like blending and interesterification. However, blending lacks uniformity, which can be overcome by interesterification. The process conditions, namely, enzyme load, temperature, substrate molar ratio, and reaction time, were systematically optimized using response surface methodology. The optimized interesterified fat was characterized for fatty acid and triacylglyceride (TAG) composition. The physicochemical and functional properties, along with oxidative stability, were also evaluated to determine its overall quality. The structured lipid with zero trans and low saturated fat was developed with 50:50 substrate molar ratio of PeO and palm stearin at 54°C within 5.4h at 6.2% w/w concentration of TLIM enzyme. It exhibited 23.8% degree of interesterification, 435.5g hardness, and 33°C slip melting point. The TAG profile of the resulting fat was significantly modified with increased triunsaturated TAGs like LnLnLn and LnLnL but reduced trisaturated TAGs like PPP. The interesterification process lowered tocopherol composition by 3%. The acid, peroxide, IP (Induction Period), and p-anisidine values of PeO significantly enhanced. The thermal behavior of the developed fat was also modified. The textural properties of margarine developed from optimized fat were comparable to commercial margarine, revealing the application of PeO in healthy margarine formulation.

Dual Metal Sites Coengineered Graphitic Carbon Nitride as Green Electrocatalyst for Highly Selective Overall Water Splitting—A Sustainable Approach

The development of efficient, low‐cost, non‐noble metal‐oxide‐based nanohybrid materials for overall water splitting is a critical strategy for enhancing clean energy use and addressing environmental issues. In this study, an interfacial engineering strategy for the development of bimetallic Co–Ni nanoparticles on graphitic carbon nitride (g‐C3N4) using ultrasonication followed by coprecipitation is conveyed. These nanoparticles demonstrate high efficacy as bifunctional electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline conditions. Co–Ni nanoparticles on graphitic carbon nitride demonstrate an increased surface area via ultrasonication and subsequent coprecipitation. The g‐C3N4 combined with Co–Ni nanoparticles leads to the development of bifunctional catalysts that exhibit significant efficiency in both HER and OER, and their interfacial properties are investigated for the first time. The chemical composition and morphology of g‐C3N4 integrated with Co–Ni nanoparticles significantly influence the modulation of redox‐active sites and the facilitation of electron transfer, resulting in improved splitting efficiency. The interactions between the Co–Ni bimetal and g‐C3N4 demonstrate exceptional electrochemical performance for water splitting. Consequently, the 20% 20–Co–Ni–graphitic carbon nitride electrode demonstrated superior HER performance, comparable to the other electrodes. In the results, it is indicated that an increased molar ratio of Co and Ni incorporated in graphitic carbon nitride significantly improves HER performance.

Development of Novel Cardanol-Derived Reactive Dispersing Agents for Bio-Based Anionic–Nonionic Waterborne Polyurethane

This study successfully developed a bio-based, photocurable, anionic–nonionic dual-functional chain extender, and sulfonated cardanol-based polyethylene glycol (SCP), derived from renewable resources—cardanol and polyethylene glycol—for application in waterborne polyurethane dispersions (WPUDs). Utilizing SCP as a chain extender, WPUDs were prepared through a typical acetone process with poly(butylene adipate) (PBA), isophorone diisocyanate (IPDI), and ethylene diamine (EDA) at a constant NCO/OH ratio of 1:1. This research focused on the effects of polyethylene glycol molecular weight and SCP dosage on the particle size, stability, and film-forming properties of the WPUD. Optimal dispersion stability and film-forming performance were achieved with a polyethylene glycol molecular weight of 1500 and a PBA to SCP molar ratio of 4:1, yielding a particle size of 0.326 ± 0.010 μm and excellent storage stability over six months. The resulting WPU coatings exhibited a tensile strength of 11.4 MPa, which increased to 16.8 MPa after UV irradiation owing to the formation of a semi-interpenetrating network via the photopolymerization of cardanol’s unsaturated side chains. UV cross-linking also enhanced water resistance, reducing the water absorption rate (WAR) from 18.68% to 4.21% and the water vapor transmission rate (WVTR) from 6.59 × 10−5 g·m⁻¹·Pa⁻¹·d⁻¹ to 2.26 × 10⁻⁵ g·m⁻¹·Pa⁻¹·d⁻¹, while also improving thermal stability. These findings demonstrate that SCP offers a sustainable and effective solution for developing high-performance WPU coatings.

Synthesis and properties of tailored β‐tricalcium phosphate for bone filler applications

AbstractThe present work reports the synthesis of highly phase pure (> 95%) β‐TCP and its subsequent conversion into granules for bone graft applications, using an industrial scale proprietary manufacturing route. Following the wet chemical approach, several process parameters, were adjusted for large volume synthesis, including pH, precursor concentration, and ripening time. The granulation process is tailored to facilitate the scalibility and control over morphology, porosity, and pore size. X‐ray diffraction analysis confirms the presence of pure β‐TCP phase where as Ca/P molar ratio of 1.497 was determined using ICP‐OES. Fourier transform infrared spectroscopy depicts the presence of PO43− as a major molecular group. Scanning electron microscopy (SEM) images of the β‐TCP powders reveal necking features, a characteristic morphology of β‐TCP. SEM images of the β‐TCP granules reveal microporosity, which aids in triggering a biological response. The TGA‐DTA curve suggests that the weight loss in pure β‐TCP is twice as compared with β‐TCP containing hydroxyapatite. Furthermore, these β‐TCP granules were clinically tested in a few orthopedic and spine surgeries. In all the treated patients, β‐TCP granules did not induce any pus formation or infection at the surgical sites, thereby establishing clinically relevant biocompatibility properties.

Conformational isomerism breaks the electrolyte solubility limit and stabilizes 4.9 V Ni-rich layered cathodes

By simply increasing the concentration of electrolytes, both aqueous and non-aqueous batteries deliver technical superiority in various properties such as high-voltage operation, electrode stability and safety performance. However, the development of this strategy has encountered a bottleneck due to the limitation of the intrinsic solubility, and its comprehensive performance has reached its limit. Here we demonstrate that the conformational isomerism of the solvent would significantly affect the solubility of electrolytes. By transforming the configuration of solvent from cis-cis to cis-trans upon thermal triggering, we successfully break the solubility limit, and a beyond concentrated electrolyte with the lowest solvent-to-salt molar ratio of 0.70 is constructed. Transitions between cis-cis and cis-trans conformers are observed through Nuclear Magnetic Resonance (NMR) testing. The electrolyte consists entirely of anion-mediated solvation structures and promotes the formation of robust inorganic-dominated cathode electrolyte interphase. As a result, it enables stable cycling of 4.9 V-class LiNi0.8Co0.1Mn0.1O2 positive electrodes. Moreover, a high capacity of 151.2 mAh g−1 can be maintained after 1000 cycles at cut-off voltage of 4.8 V. This work provides a chemical pathway to build new concept electrolytes working under harsh conditions.

Synthesis of some new transition metal complexes derived from tellurated formazanes

A novel series of organotellurium compounds based on formazane derivatives with a general formula of ArTeBr3 4 and Ar2TeBr2 5 [Ar = 2-[{4-hydroxy-3-methoxyphenyl}{4-nitrophenyldiazenyl}methylene amino]-5-nitrophenyl] were synthesized by refluxing mercurated formazane derivative ArHgCl with TeBr4 in two different mole ratios of 1:1 and 2:1, respectively, in dry dioxane solvent under an argon atmosphere. Compounds ArTeBr3 and Ar2TeBr2 were then reduced by the action of an ethanolic solution of hydrazine hydrate to obtain Ar2Te2 6 and Ar2Te 7, respectively. The ligand properties of bis(2-[{4-hydroxy-3-methoxy phenyl}{4-nitrophenyl diazenyl}methylene amino]-5-nitrophenyl) telluride (7) were examined toward several metal ions through its reaction with K2PtCl4, PdCl2 · 2 H2O, K2PtCl6, RhCl3 · 3 H2O, CoCl3 · 6 H2O and NiCl2, respectively. These compounds were characterized by FTIR, UV-Vis,1H and 13C{1H} NMR spectroscopy and mass spectrometry as well as by elemental analysis, thermal analysis, magnetic susceptibility and molar conductivity. The identification of the synthesized complexes 8-13 proved that the complexes of Pt(II), Pd(II) and Ni(II) have square pyramidal geometries and are diamagnetic, while the complexes of Pt(IV), Rh(III) and Co(III) have octahedral shapes with the same magnetic behavior. The telluride 7 behaves as a neutral pentadentate ligand.

The Influence of Conditions of Polycondensation in Acid Medium on the Structure of Oligosilsesquioxanes with a Novel Eugenol-Containing Substituent.

Eugenol-containing oligoorganosilsesquioxanes were synthesized by the method of hydrolytic polycondensation in an active medium under various reaction conditions. The obtained products were characterized by 29Si NMR spectroscopy and MALDI-TOF spectrometry. It was shown that factors such as the reaction temperature, polycondensation duration, and molar ratio between the initial alkoxysilane monomer and acetic acid may affect the molecular weight characteristics and molecular structure of the formed oligomer, like the content of stressed cyclic units (T3, DTT, TDT) and unstressed silsesquioxane units TnDm. In particular, an increase in the ratio of the initial reagents led to an increase in the content of silsesquioxane Tn fragments from 28.2%mol to 41.7%mol, while the number of strained cyclic structures decreased by more than two times. An increase in the synthesis time is of no particular practical value since it was found that the composition of the oligomers synthesized for 6 h and 12 h was practically identical, as was that of the oligomers synthesized for 24 h and 48 h. A noticeable transition in the oligomer composition was observed only when the synthesis time was changed from 12 h to 24 h. Finally, it was shown that the choice of synthesis temperature had the strongest effect on the oligomer composition. The oligomer synthesized at 95 °C contained the highest amount of silsesquioxane Tn fragments, >77%mol, while a Tn fragment content of ~42%mol was observed during the synthesis at 117 °C. It was shown that silsesquioxanes are devitrified at room temperature (Tg from -6.4 to -10.6 °C), and their thermal stability in an inert atmosphere is 300 °C. The synthesized oligomers, due to the presence of hydroxyl-containing eugenol units, may be promising binders and additives for functional epoxy-silicone paints and coating materials.

Utilization of sterculia foetida oil as a sustainable feedstock for biodiesel production: optimization, performance, and emission analysis

This study examines the feasibility of employing Sterculia foetida oil as a sustainable feedstock for biodiesel production, offering an eco-friendly substitute for conventional diesel fuel without requiring engine alterations. The method employs a two-step catalytic process, first with acid esterification to reduce the free fatty acid (FFA) concentration, followed by alkaline esterification for biodiesel synthesis. Essential process parameters—such as reaction time, temperature, catalyst concentration, and molar ratio—are carefully optimized to improve biodiesel yield. Under optimal conditions, the process achieves an impressive conversion rate of 95.2 %, demonstrating the considerable potential of Sterculia foetida oil for biodiesel production. Furthermore, blends of Sterculia foetida biodiesel (SFB) and diesel demonstrate a notable decrease in harmful emissions, especially a 2.3 % reduction in carbon monoxide (CO), a 4.1 % reduction in hydrocarbons (HC), and a 1.9 % decrease in smoke emissions compared to pure diesel. This study highlights the innovative use of non-edible oil as feedstock, a customized optimization method, and a highly effective catalytic process, all while emphasizing environmental sustainability and reduced emissions.

Corn Stover Lignin as a Solid Acid Catalyst for the Esterification of Oleic Acid

AbstractThe catastrophic ramifications of fossil fuels on the environment have prompted the search for renewable energy sources. Over the recent decades, biodiesel has garnered attention as a promising direct alternative to diesel fuel; however, reliance on homogeneous catalysts and the requirement for refined vegetable oil feedstocks present financial and sustainability concerns. Thus, there exists a need for the development of sustainable and cost‐effective catalytic solutions. Herein, the application of lignin, an abundant and renewable biomass, as an effective heterogeneous catalyst is reported for biodiesel production via the esterification of oleic acid. Lignin is extracted from corn straw using sulfuric acid, which endows sulfonic acid groups (0.85 mmol g−1) to its structure allowing it to act as an acid catalyst without additional post‐treatments. Conversion of oleic oil to biodiesel is achieved at 97% using a 1:3 oleic acid to methanol molar ratio with a 5 wt.% catalyst loading at 90 °C after only 30 min. Moreover, the catalyst exhibits a remarkable turnover frequency of 2.61 min−1 proving its efficiency. These findings demonstrate that heterogeneous catalysts can be prepared from biomass waste offering a significantly cheaper and less intensive synthesis process and allowing for a paradigm shift to non‐edible and waste cooking oils.

Aerobic Oxidation of Vanillyl Alcohol to Vanillin Over CeO2‐Co3O4 Catalyst

AbstractA promising CeO2‐Co3O4 (9 : 1 mole ratio based on oxides) non‐noble metal based mixed oxide catalyst was explored for selective oxidation of vanillyl alcohol with molecular oxygen to produce vanillin under atmosphere pressure. In particular, to enhance its efficiency, this catalyst was prepared by adopting different preparation methods namely, template assisted, coprecipitation with and without surfactant, wet‐impregnation, and solution combustion. The prepared catalysts were characterized by XRD, Raman, BET surface area, ICP‐OES, FE‐SEM, HR‐TEM, H2‐TPR, and XPS. Among various catalysts investigated, the template assisted synthesized catalyst exhibited superior activity (100 % conversion and selectivity) and high stability. The better activity of this catalyst was found to be due to reduced crystallite size, high specific surface area (92 m2/g), more surface oxygen, and improved redox behaviour as confirmed from XRD, BET surface area, XPS, and H2‐TPR analysis, respectively. The stability of the catalyst was tested by reusability test and was observed that there is not much decrease in the catalytic activity up to five cycles. Further, the catalytic activity was optimized by varying the reaction parameters such as time, solvent, temperature, and catalyst weight.

Optimization of White Tea Flavanol Extraction Process by the Ultrasonic‐Assisted Deep Eutectic Solvent Method and Determination of the Antioxidant and Antibacterial Activity

ABSTRACTFlavanols have a variety of health benefits and biological activities and become the hotspot of the food development and research. In this research, flavanols were extracted from white tea by ultrasonic‐assisted deep eutectic solvent (DES) method. High‐performance liquid chromatography was used to determine the content of flavanols. The influence of four factors on the flavanol extraction yield was analyzed by single factor experiments, including deep eutectic solvent mole ratio (the mole of hydrogen bond acceptors: the mole of hydrogen bond donors), solid–liquid ratio (white tea sample weight/g: the volume of DES/mL), extraction time and extraction temperature. On the basis of single factor experiments, the factors which had significant effects on the flavanol extraction yield were further optimized by the response surface test. The results showed that the optimized extraction conditions were as follows: the mole ratio of DES 1: 4 (choline chloride: 1,2‐propanediol), the solid–liquid ratio 1:30, the extraction temperature 56°C, the extraction time 53 min, and the ultrasonic power 341 W. Under the above parameters, the extraction yield of white tea flavanols was 9.63 mg/g. After purification with macroporous resin, antioxidation and antibacterial experiments were carried out. The results showed that the antioxidant and antibacterial effects of white tea flavanols were remarkable. The antibacterial effects performed best on Escherichia coli, followed by Bacillus subtilis and Staphylococcus aureus. The maximum diameter of the antibacterial zone on Escherichia coli was 0.95 ± 0.11 mm. The best radical scavenging rates of OH, ABTS+ and DPPH were 97.1%, 97.5%, and 88.4%, respectively, when the flavanol concentration was 9.5 mg/mL. The conclusions of this research can provide theoretical foundation for the further study of white tea flavanols.

Investigation on induced smectic phases in double hydrogen bond liquid crystal complexes derived from aromatic carboxylic acids: Experimental and quantum chemical approaches

In the present study, double Hydrogen bond liquid crystal (HBLC) complexes in different mole ratio (1:1 and 1:2) have been isolated from symmetrical aromatic dicarboxylic acid of non-mesogenic compound 1,3-Phenylenediacetic acid (1,3-PDA) and mesogenic compound 4-n-dodecyloxybenzoic acid (12 OBA). Fourier transform infrared Spectroscopy (FTIR) explores the presence of functional groups in the title complexes. Formation of H-bond between 1,3-PDA and 12 OBA is experimentally confirmed by observing the FTIR peak at 3639 cm−1 (1:1 ratio). Induced mesophases and its textures along with transition temperatures are analyzed using polarizing optical microscope (POM) and differential scanning calorimetry (DSC). The layered structures (smectic phases) and their molecular mechanism has been analyzed using density functional theory (DFT). Further, the establishment of H-bond in the title complex has been investigated with the aid of optimized geomentry, molecular electrostatic potential (MEP) and reduced density gradient (RDG) analysis. The band gap energy of title complex (1:1) is calculated by UV–Vis spectrometer and the same has been justified by HOMO-LUMO studies. Maximum absorption in the UV region and moderate bandgap energy (Eg = 4.22 eV) of the title complex clearly indicates its potential application in NLO, optoelectronics and laser tuning devices. In addition to that, LC parameters and its effect on mesophase are reported using experimental and computational methods.

Rapid and eco-friendly microextraction procedure based on green hydrophobic deep eutectic solvent for simultaneous determination of five sex hormones from cosmetic samples

Hormones, which are among the endocrine disruptors, are used in many fields and their use in cosmetic products has recently attracted considerable attention. Despite the negative health consequences, there is no detailed guidance that limits the use of these endocrine disruptors. This study aimed to develop a green hydrophobic deep eutectic solvent (HDES)-based microextraction method for the detection and quantification of sex hormones (progesterone, β-estradiol, estrone, ethinylestradiol, and testosterone) in different cosmetic products. The best value for extraction recovery was obtained by using DL-menthol and dodecanoic acid as green HDES in a 4:1 mole ratio. Optimization parameters such as HDES volume, pH, sample volume, centrifugation time, mixing type, and mixing time were investigated for cosmetic samples to be used as real samples. Furthermore, the extraction recovery values ranged from 85.7 % to 101.3 % and the detection limit was between 2.33–3.30 ng mL−1. Additionally, three different greenness methods, namely ComplexGAPI, AGREEprep, and BAGI, were used to evaluate how green the proposed method is in this study. The microextraction procedure developed in this study was successfully applied to five different cosmetic samples that will be used as real samples to detect and determine sex hormones.

Structural characteristics and antioxidant activity of a low-molecular-weight jujube polysaccharide by ultrasound assisted metal-free Fenton reaction

This study used an ultrasonically accelerated metal-free Fenton (H2O2-Vc system) reaction to promote water-extracted degrading polysaccharides from Ziziphus Jujuba cv. Muzao (DZMP). A novel jujube polysaccharide (DPZMP3) was obtained by degradation using DEAE-Sepharose Fast Flow and Sephacryl S-100 column chromatography. Methylation analysis, HPGPC, ion chromatography, FT-IR, and NMR spectroscopies were used to clarify the chemical structures of DPZMP3. Monosaccharide compositional analysis of DPZMP3 revealed the presence of Rha, Ara, Gal, and GalA at a molar ratio of 1.00:1.49:1.60:7.68, and the HPGPC data demonstrated the average Mw of 34.3 kDa. Based on the structural and linkage research using NMR spectroscopy and GC–MS, it was determined that DPZMP3 was a homogalacturonan pectic polysaccharide with a (1 → 4)-Galp branch at C-6 and a small amount of Araf and Rhap residues. The ultrasonic-aided Fenton treatment did not significantly alter the structure of DPZMP3. It may also be useful for DZMP and enhancing their antioxidant activity in vitro. The current study's findings could pave the way for the food sector to use jujube polysaccharides obtained by degradation as a functional food component.

Study on properties and CO2 emission of self-pulverizing calcium sulfoaluminate (SPCSA) after carbonization curing

The extensive use of Portland cement (OPC) has resulted in a steady rise in CO2 emissions from the construction industry, posing a significant climate threat. While adopting low-carbon cement enriched with belite minerals holds promise for substantial CO2 emission reduction in the cement industry, the limited early hydration activity of C2S constrains its engineering applications. Carbon capture, storage, and utilization (CCUS) technology, capable of rapidly developing the strength of C2S, opens up a new avenue for utilizing low-carbon cement. This study evaluated the properties of self-powdering calcium sulfoaluminate (SPCSA) cements with different C2S contents, and the carbon emissions during production and application were analyzed. The samples' carbonation area, compressive strength, and capillary water absorption properties were tested. The carbonation products and pore structures were also characterized using XRD, TGA, SEM, and Low-NMR. The results show that when the molar ratio of C4A3S̅ to C2S is 1:12 (S̅12), the compressive strength and CO2 sequestration of SPCSA are 69.78 MPa and 0.15 g/g, respectively. When CCUS technology is adopted, the CO2 emission during the production and application of SPCSA is 585.78 kg/t, much lower than that of OPC of 878.28 kg/t. This is significant as a reference for realizing carbon neutrality in the cement industry.

Harnessing in-situ oxidation of nanostructured mxene to modulate the electronic structure for improved selectivity for electrochemical carbon dioxide reduction

The electrochemical CO2 reduction reaction (CO2RR) is a promising approach to valorizing CO2. Ti3C2TX as a support material has received significant interest in enhancing CO2RR performance for tuning the electronic structure. However, there has been relatively less focus on changes to the Ti3C2TX electronic structure induced by loading catalysts onto the Ti3C2TX. Because Ti3C2TX has an intrinsic activity for both CO2RR and the competitive hydrogen evolution reaction (HER), electronic structure changes can affect the balance between CO2RR and HER selectivity. Therefore, tuning the electronic structure of Ti3C2TX can control the competition between CO2RR and HER and tune the selectivity and activity. Herein, we report that Ti3C2TX’s electronic structure can be tuned by the Ag+ loading method via redox interactions, tuning the reaction selectivity and activity for CO2RR. To illustrate this effect, we compare the CO2RR performance of in-situ formed Ag nanoparticles (NPs) on Ti3C2TX (0.9Ag-IS-Ti3C2TX) with physically mixed Ag NPs and Ti3C2TX (0.9Ag/P/Ti3C2TX). Here, ‘0.9’ refers to the molar ratio between Ag precursor and Ti3C2Tx, and ‘IS’ vs. ‘P’ refers to in-situ formed vs. physically mixed Ag NPs. 0.9Ag-IS-Ti3C2TX demonstrates a higher oxidation state for Ti and a higher proportion of Ti-O bonds than 0.9Ag/P/Ti3C2TX. Compared to 0.9Ag/P/Ti3C2TX, 0.9Ag-IS-Ti3C2TX exhibits higher CO Faradaic efficiency (FE), rising from 8.1 % with a partial current density of −2.0 mA cm−2 to 49.6 % with a partial current density of −20.1 mA cm−2 at −1.4 V vs. RHE (reversible hydrogen electrode). To harness this effect, we demonstrate control over the CO: H2 ratio of syngas formed from CO2RR over our Ti3C2TX-supported catalysts. Further electrochemical anodic oxidation experiments reveal the critical oxidation potential of Ti3C2TX (0.8 V vs. RHE) and show that HER can be partially suppressed by partial oxidation of Ti3C2TX. This work highlights the importance of considering the changes in Ti3C2TX (and other) supports when supporting catalysts for CO2RR and other electrochemical reactions.

Utilization of waste from paper industry as a heterogeneous base catalyst for the synthesis of biodiesel

AbstractTo meet the pressing demand for alternative biofuel in the contemporary world, the production cost of biodiesel has to be decreased. Hence, this work addresses the usage of CaCO3‐rich industrial waste produced in a local paper industry in Assam, India for the synthesis of a heterogeneous catalyst for biodiesel synthesis. The collected lime sludge waste was subjected to calcination at 800°C for 3 h producing a CaO‐rich catalyst which was then employed in the transesterification of cottonseed oil. The optimized reaction conditions obtained were 5 wt% catalyst concentration, oil to methanol molar ratio of 1:12 at 65°C temperature, and 3 h of reaction time. The catalyst's reusability was evaluated up to four cycles. Besides, the prepared catalyst has been characterized using Fourier transfer infrared spectroscopy (FTIR), powder X‐ray Diffraction (p‐XRD), Scanning Electron Microscope (SEM), Energy Dispersive X‐ray analysis (EDX), and Brunauer–Emmett–Teller (BET) techniques and its basicity was measured using Hammett indicators. Moreover, the biodiesel obtained was characterized with 1H‐nuclear magnetic resonance (NMR), 13C‐NMR, Gas Chromatography‐ Mass Spectrometry (GC–MS), and FTIR techniques. A biodiesel yield of 98.03% was achieved and the quality of biodiesel formed during the transesterification of CSO also conforms to EN 14214 and ASTM D 6751 standards. Thus, our study highlights the sustainability and the potential for future industrial application of paper industrial waste in the production of biodiesel.

Waterborne Polyurethane Micelles Reinforce PEO-Based Electrolytes for Lithium Metal Batteries.

Although solid polymer electrolytes have been developed for several decades, poly(ethylene oxide) (PEO) or polymers with ethoxy (EO) segments are still one of the most promising candidates for advanced batteries. The low ionic conductivity and lithium-iontransference number as well as the deterioration of mechanical properties after coupling with lithium salts restrict its further adoption. Herein, a serial of PEO-based composite electrolytes optimized by waterborne polyurethane are prepared via blend method. With the assistance of H2O, ionic type waterborne polyurethane assembles into flexible micelles, in which hydrophobic segments as the core and hydrophilic groups as the shell. Utilizing this feature of waterborne polyurethane, PEO and Li salt (LiTFSI) aqueous solution is slowly added to the organic solution of waterborne polyurethane to compoundin situ, and polymer composite electrolytes are fabricated. The multilevel (hydrogen bonds with different binding energy) and multiscale (deformation of flexible micelles) dynamic interaction endows the composite electrolyte with attractive mechanical properties. The assembled Li|Li symmetric battery with the molar ratio of EO to Li salts of 8:1 exhibits excellent cycling stability up to 800 h at 0.1 mA cm-2, and the assembled Li|LiFePO4battery can be stably cycled at 1C for >400 cycles.

Investigation on preparation and properties of gel type 188W/188Re generator

As one of the most important integrated nuclides for diagnosis and treatment in recent years, rhenium-188 (188Re) has a broad scope in the clinical application. Due to the specific properties of such radionuclide, it was mainly provided by the chromatographic 188W-188Re generators. There is no doubt that the application of 188Re in the treatment of various diseases depended on the development of 188W-188Re generator. Considering the high standards of such technology on radioactive activity of 188W and impurity content, a 188W-188Re generator filled with the zirconium tungstate gel has been prepared in this work. The effects of molar ratio of chemical agents, pH, reaction temperature, drying methods, rinsing methods and other conditions on the synthesis of gel particles have been studied. Furthermore, a variety of characterization techniques were used to observe the macro-/micro-morphology and chemical structure of gel particles. It can be concluded that vacuum freeze-dried method could significantly increase the specific surface area, pore size and tungsten content of gel particle. In order to decrease the content of 188W in the elute, a handful of acidic alumina was filled in the bottom of our 188W-188Re generator, an elution and purification integrated-generator was formed. During the first five processes, the nuclear purity of 188Re solution was above 99.99%, the radiochemical purity was approximately 99.5%, the pH value was 5.0–7.0 and the average elution efficiency reached up to 82.7%. In addition, the leakage rate of 188W was low as 1.60 × 10−6, and the peak of elute curve was located at 2 mL without the trailing phenomenon. This work lays a solid foundation for the domestic demand of daughter nuclide 188Re, further makes an outstanding contribution to the application of the radiation therapy technology and the protection of people's health.