Precursors Glycerol Research Articles

Novel cocatalyst MnCo2S4 based on Zn3In2S6 for enhanced photocatalytic hydrogen production and ranitidine degradation

Photocatalysis offers a sustainable method for producing hydrogen and degrading harmful substances such as ranitidine. In this research, metal-like properties of MnCo2S4 nanoparticles were synthesized using a glycerol precursor and integrated into Zn3In2S6 floral microsphere via a low-temperature hydrothermal method to function effectively as a cocatalyst. The catalyst not only exhibits excellent hydrogen production efficiency but also demonstrates outstanding performance in degrading ranitidine. Under visible light irradiation, the MnCo2S4/Zn3In2S6 composite material reached a maximum hydrogen production rate of 4471.7 µmol·g−1·h−1 within 6 h, which is 10.6 times higher than that of pure Zn3In2S6. After 24 h of reaction over 4 continuous cycles, the hydrogen evolution activity maintained 94.86 % of its initial performance. Additionally, after 60 min of visible light exposure, the composite achieved a ranitidine degradation rate of 94.7 %, significantly surpassing the performance of pure Zn3In2S6. This exceptional photocatalytic activity is attributed to the synergistic interactions between Zn3In2S6 and the conductive cocatalyst MnCo2S4, which facilitate interfacial charge transfer. A potential reaction mechanism was proposed, supported by a series of experiments and characterization techniques. The formation of a Schottky junction at the MnCo2S4/Zn3In2S6 interface enables rapid electron transfer to the MnCo2S4 nanoparticles, preventing electron backflow and thus promoting effective separation of photo-induced charge carriers. Therefore, this study introduces a novel approach for designing metal-semiconductor photocatalysts for efficient hydrogen production and ranitidine degradation.

Spinel-structured MnV2O4 @nitrogen-doped carbon microspheres for sodium ion batteries with ultra-long cycle stability

Vanadium oxide is provided with abundant redox centers for high theoretical capacity as anode of sodium-ion batteries (SIBs), but still has poor inherent conductivity and volume expansion leading to fast capacity decay during cycling. In the study, the manganese vanadate microspheres enclosed in nitrogen-doped carbon layers (MnV2O4 @NC) are availably constructed via reflux vanadization of Mn glycerol precursor and in situ thermal decomposition. The MnV2O4 @NC microspheres shows excellent the long-cycle stability as anode materials for SIBs, remaining the specific capacity of 205 mAh g−1 at current of 1000 mA g−1 after nearly 4000 cycles. Due to the increased valence range of bimetallic oxides and three-dimensional channels of spinel structure, the cubic MnV2O4 encapsulated by carbon shell can effectively enhance charge transfer, optimize electronic structure, stabilize crystal structure, and improve cycle stability. These results disclose the prospects of vanadate-based spinel material in high performance SIBs.

Polynary metal selenide CoSe2/NiSe2/MoSe2 porous nanospheres as efficient electrocatalytic materials for high-efficiency dye-sensitized solar cells

• CoSe 2 /NiSe 2 /MoSe 2 porous nanosphere was synthesized. • CoSe 2 /NiSe 2 /MoSe 2 had abundant active sites and excellently catalytic activities. • The PCE of CoSe 2 /NiSe 2 /MoSe 2 (9.49%) was higher than that of Pt (8.28%). Transition metal selenides with porous structure have a brightly prospects due to their low cost, large surface area, high catalytic efficiency, and facile synthetic method comparing with Pt-based electrocatalytic materials in power transformation systems. Herein, we have successfully prepared porous structure transition metal selenide CoSe 2 /NiSe 2 /MoSe 2 nanospheres through simple solvothermal method and stepwise selenization process from glycerol precursor nanospheres. Uniform selenide nanoparticles were formed on the surface of the porous nanospheres. The resultant CoSe 2 /NiSe 2 /MoSe 2 porous nanospheres not only provided more redox pairs, but also had better electron transfer performance and shorter charge transfer distance between the electrolyte and the electrode materials, accelerating the charge transfer process. Therefore, CoSe 2 /NiSe 2 /MoSe 2 nanospheres delivered excellent electrochemical performance in dye-sensitized solar cells which achieved an excellent power conversion efficiency of 9.49% comparing to the cell based on Pt (8.28%). This work can offer a new vision on the design of high-performance, environment-friendly, and Pt-free electrocatalysts for solar cells.

Estimation of Individual Glucose Reserves in High-Yielding Dairy Cows

Glucose plays a central role in numerous physiological processes in dairy cows related to immune defence and milk production. A lack of glucose impairs both objectives, although to different degrees. A method for the estimation of glucose balance (GB) in dairy cows was developed to assess glucose reserves in the intermediary metabolism. Digestive fluxes of glucogenic carbon were individually estimated via the Systool Web application based on data on body weight (BW), dry matter intake (DMI), and chemical analyses of feedstuffs. Fluxes of endogenous precursors glycerol, alanine and L-lactate and the glucose demand imposed by major glucose-consuming organs were deduced from BW, lactose yield and lactation stage. GB was calculated for 201 lactations (1 to 105 DIM) of 157 cows fed isoenergetic rations. Individual DMI, BW and milk yield were assessed on a daily basis. The results showed that the GB varied greatly between cows and lactation stages. In the first week of lactation, average daily GB reached levels close to zero (3.2 ± 13.5 mol C) and increased as lactation progressed. Most cows risk substantial shortages of glucose for maintenance during the first weeks of lactation. In face of the specific role of glucose for the functional capability of the immune function, the assessment of glucose reserves is a promising measure for the identification of cows at risk of impaired immunocompetence.

Heterologous Production of Acrylic Acid: Current Challenges and Perspectives

Acrylic acid (AA) is a chemical with high market value used in industry to produce diapers, paints, adhesives and coatings, among others. AA available worldwide is chemically produced mostly from petroleum derivatives. Due to its economic relevance, there is presently a need for innovative and sustainable ways to synthesize AA. In the past decade, several semi-biological methods have been developed and consist in the bio-based synthesis of 3-hydroxypropionic acid (3-HP) and its chemical conversion to AA. However, more recently, engineered Escherichia coli was demonstrated to be able to convert glucose or glycerol to AA. Several pathways have been developed that use as precursors glycerol, malonyl-CoA or β-alanine. Some of these pathways produce 3-HP as an intermediate. Nevertheless, the heterologous production of AA is still in its early stages compared, for example, to 3-HP production. So far, only up to 237 mg/L of AA have been produced from glucose using β-alanine as a precursor in fed-batch fermentation. In this review, the advances in the production of AA by engineered microbes, as well as the hurdles hindering high-level production, are discussed. In addition, synthetic biology and metabolic engineering approaches to improving the production of AA in industrial settings are presented.

Synthesis of nanosized LaFeAl11O19 hexaaluminate by mixed metal glycerolate method

A novel method for the synthesis of perspective hexaaluminate LaFeAl11O19 was developed and the product was identified as cubical nanoparticles with a diameter of 45 nm and thoughtfully characterized by SEM-EDS, XRD, BET and HRTEM measurements. As a precursor, amorphous synthetized mixed metal glycerolate was used. Synthesis of the LaFeAl11O19 was made by thermal decomposition of the glycerolate, which was studied by STA measurements. The method is easy to scale up as both glycerolate precursor and subsequent thermal decomposition are simple and relatively affordable methods and the resulting product can be used both in industry and research, especially for catalysis.

Novel synthesis and electrochemical investigations of ZnO/C composites for lithium-ion batteries

For the first time, ZnO/C composites were synthesized using zinc glycerolate as a precursor through one-step calcination under a nitrogen atmosphere. The effect of the heat treatment conditions on the structure, composition, morphology as well as on the electrochemical properties regarding application in lithium-ion batteries are investigated. The products obtained by calcination of the precursor in nitrogen at 400—800 °C consist of zinc oxide nanoparticles and amorphous carbon that is in-situ generated from organic components of the glycerolate precursor. When used as anode material for lithium-ion batteries, the as-prepared ZnO/C composite synthesized at a calcination temperature of 700 °C delivers initial discharge and charge capacities of 1061 and 671 mAh g−1 at a current rate of 100 mA g−1 and hence 1.5 times more than bare ZnO, which reaches only 749/439 mAh g−1. The native carbon improves the conductivity, allowing efficient electronic conductivity and Li-ion diffusion. By means of ex-situ XRD studies a two-step storage mechanism is proven.

A combined electrochemical, infrared and EDXD tool to disclose Deep Eutectic Solvents formation when one precursor is liquid: Glyceline as case study

Deep Eutectic Solvents (DESs) are gathering growing attention as sustainable solvents in different fields ranging from synthesis to electrochemical devices. Albeit DES are widely employed, the fundamental knowledge on their interspecies relations is still partial. Understanding the chemistry of this class of green solvent is an essential step to further tune their properties. In this study, we report a detailed experimental and theoretical investigation of two choline-chloride glycerol mixtures using electrochemical, spectroscopic (Raman/Far Infrared), diffraction (X-ray) and molecular simulation methods. Remarkably different Far-infrared spectra have been surprisingly collected for the two mixtures. Differences are attributed to the deconstruction of the extended hydrogen bond network characteristic of pure glycerol and of the 1:2 mixture and absent in the glycerol-richer mixture 1:3. From the analysis of X-ray profiles, that are very well reproduced by molecular dynamics, it was found that the lack of the glycerol H-bond interactions in the glycerol-richer mixture (Ch:Gly 1:3) can be attributed to the establishment of a full coordination shell of polyalcohol molecules around the chloride anion. In the 1:2 composition the coordination is probably defective, as signaled by the FIR spectrum that significantly maintains the features observed for the precursor glycerol, and the chloride stabilization is ensured by interaction with both choline hydroxyl and electrostatic interactions.

First principles study of reactions in alucone growth: the role of the organic precursor.

Organic-inorganic hybrid materials are a unique class of materials with properties driven by the organic and inorganic components, making them useful for flexible devices. Molecular layer deposition (MLD) offers novel pathways for the fabrication of such hybrids by using inorganic metal precursors and the vast range of organic molecules with tunable properties. To investigate and understand the mechanism of growth a combination of theoretical and experimental data is needed. In this contribution, we present a first principles investigation of the molecular mechanism of the growth of hybrid organic-inorganic thin films of aluminium alkoxides, known as "alucones" grown by MLD. We explore the interactions between precursors by analyzing the MLD reaction products of the alumina surface terminated with Al(CH3) groups after the trimethyl aluminium pulse; this yields monomethyl-Al2O3 (Al-CH3-Al2O3) and dimethyl-Al2O3 (Al(CH3)2-Al2O3) terminated surfaces. The organic precursors are ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG) and tetraethylene glycol (FEG). A detailed comparison with alucones grown with ethylene glycol (EG) and glycerol (GL) precursors is presented to assist the interpretation of experimental findings regarding the differences in the hybrid films grown by EG and GL. The results show that Al-O formation with release of methane is favorable for all precursors. EG and GL can lie flat and create so-called double reactions through the reaction of the two terminal hydroxyl groups with the surface fragments. This phenomenon removes active hydroxyl sites for EG. However, for GL the third hydroxyl group is available and growth can proceed. This analysis shows the origin of differences in thickness of alucones found for EG and GL.

Hierarchical Ni-MoSex@CoSe2 core-shell nanosphere as highly active bifunctional catalyst for efficient dye-sensitized solar cell and alkaline hydrogen evolution

Core-shell structured nanocomposites based on transition metal selenides have a broad development prospect as Pt-free electrocatalyst in energy conversion due to large surface area, rich edge sites, as well as synergistic interactions between the core and shell. Herein, the preparation of core-shell structured transition metal selenides nanospheres was achieved through a facile wrapping process using zeolitic imidazolate framework (ZIF-67) as the cobalt source, which assembled on glycerol precursor nanospheres. After a selenization treatment, this formed core-shell structure had a Ni-MoSex inner core, supporting the CoSe2 outer shell (denoted as Ni-MoSex@CoSe2 CSNs). And the resultant Ni-MoSex@CoSe2 CSNs not only had a large number of active sites, but also was good for adsorbing/transferring iodine and hydrogen ions. Therefore, Ni-MoSex@CoSe2 delivered superior performance in dye-sensitized solar cells (DSSCs) and alkaline hydrogen evolution reactions (HERs). DSSCs based on Ni-MoSex@CoSe2 CSNs performed an outstanding power conversion efficiency (PCE) of 9.58% which was much higher than that of Pt (8.32%). A lower onset potential of 37.5 mV and a smaller Tafel slope of 68.9 mV dec−1 were achieved by Ni-MoSex@CoSe2 as electrocatalysts for HER in 1.0 M KOH. This work affords a new idea for the design of cut-price core-shell nanomaterials with high efficiency and can be extended to the synthesis of other electrocatalysts substituting Pt-based catalysts.

TiO2/C nanocomposites prepared by thermal annealing of titanium glycerolate as anode materials for lithium-ion batteries

TiO2/C nanocomposites have been synthesized by developing a facile route based on the annealing of titanium glycerolate in inert atmosphere at 250–850 °C. X-ray diffraction studies reveal that the annealing temperature determines the crystal structure of the TiO2 phase in the compounds, which can be amorphous, anatase, and rutile. In contrast, the nanosized rod-like morphology which to a certain extent is predefined by the titanium glycerolate precursor does not depend on the annealing temperature. The carbon content of the TiO2/C composites amounts to 16–29 wt% and shows up, e.g., in the characteristic Raman D and G bands. Anatase-structured TiO2/C, which is obtained at 600 °C, exhibits the best electrochemical performance among the studied materials. Without the addition of carbon black, it reaches an initial specific discharge capacity of 378 mA h g−1 at 100 mA g−1 and exhibits excellent rate capability with a capacity of 186 mA h g−1 at 1000 mA g−1.

Next-Generation Probiotics Targeting Clostridium difficile through Precursor-Directed Antimicrobial Biosynthesis.

Integration of antibiotic and probiotic therapy has the potential to lessen the public health burden of antimicrobial-associated diseases. Clostridium difficile infection (CDI) represents an important example where the rational design of next-generation probiotics is being actively pursued to prevent disease recurrence. Because intrinsic resistance to clinically relevant antibiotics used to treat CDI (vancomycin, metronidazole, and fidaxomicin) is a desired trait in such probiotic species, we screened several bacteria and identified Lactobacillus reuteri to be a promising candidate for adjunct therapy. Human-derived L. reuteri bacteria convert glycerol to the broad-spectrum antimicrobial compound reuterin. When supplemented with glycerol, strains carrying the pocR gene locus were potent reuterin producers, with L. reuteri 17938 inhibiting C. difficile growth at a level on par with the level of growth inhibition by vancomycin. Targeted pocR mutations and complementation studies identified reuterin to be the precursor-induced antimicrobial agent. Pathophysiological relevance was demonstrated when the codelivery of L. reuteri with glycerol was effective against C. difficile colonization in complex human fecal microbial communities, whereas treatment with either glycerol or L. reuteri alone was ineffective. A global unbiased microbiome and metabolomics analysis independently confirmed that glycerol precursor delivery with L. reuteri elicited changes in the composition and function of the human microbial community that preferentially targets C. difficile outgrowth and toxicity, a finding consistent with glycerol fermentation and reuterin production. Antimicrobial resistance has thus been successfully exploited in the natural design of human microbiome evasion of C. difficile, and this method may provide a prototypic precursor-directed probiotic approach. Antibiotic resistance and substrate bioavailability may therefore represent critical new determinants of probiotic efficacy in clinical trials.

Simple synthesis of free surface nanostructured spinel NiFe2O4 with a tunable particle size

Nanostructured nickel ferrite stoichiometric spinel NiFe2O4 is intensively studied as a material suitable for catalysts or medical applications. Thus, it is very important to find a simple and cost-effective method for the synthesis of nanoparticles with homogenous and tunable particle size. In this work, we successfully synthetized nickel ferrite nanoparticles by thermal decomposition of nickel-iron glycerolate in a dynamic air atmosphere at different temperatures. We studied the thermal decomposition process by STA. The nickel-iron glycerolate precursor was analyzed by XRD, XPS, AAS, Raman spectroscopy, EDS and SEM to obtain exact composition and information about the morphology. The particle size of the obtained nanoparticles was determined from XRD diffraction patterns using Scherrer equation and also by TEM. Magnetic properties were studied using VSM in PPMS.

472 Anti-inflammatory actions of phosphatidyl glycerol and its precursor glycerol in vitro and in an in vivo mouse model of psoriasis

472 Anti-inflammatory actions of phosphatidyl glycerol and its precursor glycerol in vitro and in an in vivo mouse model of psoriasis

1,2,3-Trimethoxypropane: A Glycerol-Derived Physical Solvent for CO2 Absorption

1,2,3-Trimethoxypropane (1,2,3-TMP) is the trimethyl ether of propane-1,2,3-triol, better known as glycerol, which can be derived from triglycerides originating from either plant or animal sources. Despite its simple structure and the ubiquity of its glycerol precursor, successful synthesis of 1,2,3-TMP was only recently reported in the literature, with studies suggesting it may be a “green” and nontoxic alternative to solvents such as diglyme, a constitutional isomer. However, no thermophysical properties of 1,2,3-TMP have yet been reported. Furthermore, the structure of 1,2,3-TMP is also analogous to polyether solvents used in the Selexol process for removal of CO2 and other “acid” gases from CH4, H2, etc. As such, examining the solubility of CO2 in 1,2,3-TMP is also of interest. This work details our initial studies and characterization of 1,2,3-TMP as a physical solvent for CO2 absorption, as well as the characterization of its density, viscosity, and vapor pressure with respect to temperature. 1,2,3-...

Thickness-ultrathin and bismuth-rich strategies for BiOBr to enhance photoreduction of CO2 into solar fuels

Two dimension layered BiOX (X=Cl, Br, I) semiconductor nanomaterials are very important photocatalysts. Our previous work showed that thickness-ultrathin and bismuth-rich strategies are excellent methods to improve the visible-light-driven (VLD) photocatalytic reduction activity of BiOX. In this study, thickness-ultrathin and bismuth-rich strategies were ingenuously combined to enhance the photocatalytic performance of the photocatalyst, via a glycerol precursor route, Bi4O5Br2 microsphere assembled by ultrathin nanosheets was synthesized and characterized by X-ray diffraction (XRD) patterns, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), high-resolution transmission electron microscopy (HRTEM), time-resolved PL spectra and UV–vis diffuse reflectance spectra (DRS). The thickness of Bi4O5Br2 ultrathin nanosheets was about 3.7nm, which was much thinner than the common BiOBr nanosheets (65nm). Due to the thickness-ultrathin and bismuth-rich strategies, the synthesized Bi4O5Br2 sample displayed a higher photocatalytic reduction activity of CO2 conversion than BiOBr and ultrathin BiOBr under visible-light irradiation. More importantly, we found that thickness-ultrathin and bismuth-rich strategies played different roles. Thickness-ultrathin strategy only can increase the CO generation while bismuth-rich strategy only can increase the CH4 generation for photoreduction of CO2.

Precursor-mediated synthesis of double-shelled V2O5hollow nanospheres as cathode material for lithium-ion batteries

Hollow micro-/nanostructures have a wide range of applications in catalysis, rechargeable batteries, drug delivery, and gas sensors, as well as energy storage and conversion. Herein, we report a facile, template-free, precursor-mediated method to synthesize V2O5 nanomaterials with three different architectures: double-shelled hollow nanospheres, single-shelled hollow nanospheres and nanoparticles. These V2O5 nanostructures are obtained via a simple thermal treatment in air of a “pre-synthesized” vanadyl glycerolate precursor, and their morphologies can be easily tuned by varying the thermal treatment temperatures. Electrochemical studies show that the double-shelled V2O5 hollow nanospheres as a cathode material for lithium-ion batteries deliver an initial capacity of 256.7 mA h g−1 with a Coulombic efficiency of nearly 100%, and their capacity is superior to the two other V2O5 nanostructures (i.e., single-shelled hollow nanospheres and nanoparticles), mainly due to their unique double-shelled hollow structure.

Atlantic cod (Gadus morhua) larvae can biosynthesis phospholipid de novo from 2-oleoyl-glycerol and glycerol precursors.

The dietary requirement of phospholipid (PL) of fish larvae has been suggested to originate in an inefficient ability for de novo biosynthesis of PL based on dietary triacylglycerol (TAG). The main objective of the present study was to investigate whether cod larvae could synthesis PL from sn-2-monoacylglycerol (2-MAG) and glycerol precursors. A tube feeding method was used to deliver equal molar aliquots of 2-oleoyl-[1,2,3-(3)H]glycerol and [U-(14)C] glycerol together with bovine serum albumin (BSA) bound 16:0 (palmitic acid) and 22:6n-3 (docosahexaenoic acid, DHA), with or without choline chloride to the foregut of anesthetized cod larvae and thereafter monitoring the metabolism of these components in the larvae through 4 h following injection. Our results showed that both 2-MAG and glycerol precursors contributed to the de novo synthesis of phosphatidylcholine (PC) and the 2-MAG pathway predominated over the G-3-P (glycerol-3-phosphate) pathway in the synthesis of TAG and PC. The molecular ratio of PC/TAG obtained from the 2-MAG and the G-3-P pathways was 0.44-0.74 and 1.02-2.06 within the first hour of tube feeding, suggesting they might have comparable biosynthesis ability of PC and TAG under the conditions of the present study. Furthermore, supplementation of choline chloride significantly increased PC/TAG ratio (p < 0.05) for both pathways. However, further studies are needed to quantify the enzyme activity involved in the CDP-choline (cytidine diphosphate choline) pathway, and the function of choline either in simulating PC synthesis or TAG catabolism or both needs further investigation.

Simple synthesis of Cr2O3 nanoparticles with a tunable particle size

Chromium oxide nanoparticles are used for industrial applications such as catalysts and pigments. Thus, it is very important to find a simple and cost-effective method for the synthesis of nanoparticles with homogenous and tunable particle size. In this work we successfully synthesized chromium(III) oxide nanoparticles by thermal decomposition of chromium glycerolate in a dynamic air atmosphere at different temperatures. The thermal behavior during the decomposition was analyzed by simultaneous thermal analysis. The chromium glycerolate precursor was analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive spectroscopy and scanning electron microscopy to obtain exact composition and information about the morphology. The particle size of the obtained nanoparticles was determined from XRD diffraction patterns using Scherrer equation and also by transmission electron microscopy. We also decomposed chromium glycerolate in argon atmosphere leading to the synthesis of two phase sample containing both the chromium(III) oxide and chromium carbide.

Reversible High‐Capacity Si Nanocomposite Anodes for Lithium‐ion Batteries Enabled by Molecular Layer Deposition

The molecular-layer deposition of a flexible coating onto Si electrodes produces high-capacity Si nanocomposite anodes. Using a reaction cascade based on inorganic trimethylaluminum and organic glycerol precursors, conventional nano-Si electrodes undergo surface modifications, resulting in anodes that can be cycled over 100 times with capacities of nearly 900 mA h g(-1) and Coulombic efficiencies in excess of 99%.