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Fulltext Stabilizing effect of various polyols on the native and the denatured states of glucoamylase

Zaroog MS, Abdul Kadir H, Tayyab S

ScientificWorldJournal, 2013;2013:570859.
PMID: 24163624 DOI: 10.1155/2013/570859

Different spectral probes were employed to study the stabilizing effect of various polyols, such as, ethylene glycol (EG), glycerol (GLY), glucose (GLC) and trehalose (TRE) on the native (N), the acid-denatured (AD) and the thermal-denatured (TD) states of Aspergillus niger glucoamylase (GA). Polyols induced both secondary and tertiary structural changes in the AD state of enzyme as reflected from altered circular dichroism (CD), tryptophan (Trp), and 1-anilinonaphthalene-8-sulfonic acid (ANS) fluorescence characteristics. Thermodynamic analysis of the thermal denaturation curve of native GA suggested significant increase in enzyme stability in the presence of GLC, TRE, and GLY (in decreasing order) while EG destabilized it. Furthermore, CD and fluorescence characteristics of the TD state at 71°C in the presence of polyols showed greater effectiveness of both GLC and TRE in inducing native-like secondary and tertiary structures compared to GLY and EG.

Matched MeSH terms: Ethylene Glycol/pharmacology
Simulation of Deep Eutectic Solvents' Interaction with Membranes of Cancer Cells Using COSMO-RS

Mbous YP, Hayyan M, Wong WF, Hayyan A, Looi CY, Hashim MA

J Phys Chem B, 2020 10 15;124(41):9086-9094.
PMID: 32930594 DOI: 10.1021/acs.jpcb.0c04801

Deep eutectic solvent (DES) affinities with cellular membranes structures dictate the degree of cytotoxicity that results from these interactions. The physicochemical properties of choline chloride (ChCl)-DESs suggest non-negligible cytotoxicities that were attested by published researches. In this study, the profiles of novel N,N-diethylammonium chloride (DAC)-based-deep eutectic solvents (DESs) prepared with various hydrogen bond donors (urea, glycerol, ethylene glycol, malonic acid, and zinc chloride) were compared to those of ChCl-DESs by using HelaS3, AGS, MCF-7, and WRL-68 cancer cell lines. The molecular interactions between salts and cellular membranes were investigated to explain the observed cytotoxicity. The results show that ChCl-based DESs (279 ≤ IC50 ≥ 1260 mM) were less toxic than DAC-based DESs (37 ≤ IC50 ≥ 109 mM). COSMO-RS analysis emphasized the importance of salt hydrophobicity with regards to DESs cytotoxicity. Malonic acid increased hydrophobicity and cytotoxicity in general, thus highlighting the potential of ammonium salt-based DESs as anticancer agents.

Matched MeSH terms: Ethylene Glycol
Exergetic performance evaluation of a diesel engine powered by diesel/biodiesel mixtures containing oxygenated additive ethylene glycol diacetate

Amid S, Aghbashlo M, Peng W, Hajiahmad A, Najafi B, Ghaziaskar HS, et al.

Sci Total Environ, 2021 Oct 20;792:148435.
PMID: 34147796 DOI: 10.1016/j.scitotenv.2021.148435

A diesel engine running on diesel/biodiesel mixtures containing ethylene glycol diacetate (EGDA) was investigated from the exergoeconomic and exergoenvironmental viewpoints. Biodiesel was mixed with petrodiesel at 5% and 20% volume ratios, and the resultant mixtures were then doped with EGDA at 1-3% volume ratios. The exergetic sustainability indicators of the engine operating on the prepared fuel formulations were determined at varying engine loads. The indicators were selected to support decision-making on fuel composition and engine load following thermodynamic, economic, and environmental considerations. The engine load markedly affected all the studied exergetic parameters. The highest engine exergetic efficiency (39.5%) was obtained for petrodiesel doped with 1 v/v% EGDA at the engine load of 50%. The minimum value of the unit cost of brake power exergy (49.6 US$/GJ) was found for straight petrodiesel at full-load conditions, while the minimum value of the unit environmental impact of brake power exergy (29.9 mPts/GJ) was observed for petrodiesel mixed with 5 v/v% biodiesel at the engine load of 75%. Overall, adding EGDA to fuel mixtures did not favorably influence the outcomes of both exergetic methods due to its energy-intensive and cost-prohibitive production process. In conclusion, although petrodiesel fuel improvers such EGDA used in the present study could properly mitigate pollutant emissions, the adverse effects of such additives on thermodynamic parameters of diesel engines, particularly on exergoeconomic and exergoenvironmental indices, need to be taken into account, and necessary optimizations should be made before their real-world application.

Matched MeSH terms: Ethylene Glycol
Fulltext Mass production of highly-porous graphene for high-performance supercapacitors

Amiri A, Shanbedi M, Ahmadi G, Eshghi H, Kazi SN, Chew BT, et al.

Sci Rep, 2016 09 08;6:32686.
PMID: 27604639 DOI: 10.1038/srep32686

This study reports on a facile and economical method for the scalable synthesis of few-layered graphene sheets by the microwave-assisted functionalization. Herein, single-layered and few-layered graphene sheets were produced by dispersion and exfoliation of functionalized graphite in ethylene glycol. Thermal treatment was used to prepare pure graphene without functional groups, and the pure graphene was labeled as thermally-treated graphene (T-GR). The morphological and statistical studies about the distribution of the number of layers showed that more than 90% of the flakes of T-GR had less than two layers and about 84% of T-GR were single-layered. The microwave-assisted exfoliation approach presents us with a possibility for a mass production of graphene at low cost and great potentials in energy storage applications of graphene-based materials. Owing to unique surface chemistry, the T-GR demonstrates an excellent energy storage performance, and the electrochemical capacitance is much higher than that of the other carbon-based nanostructures. The nanoscopic porous morphology of the T-GR-based electrodes made a significant contribution in increasing the BET surface as well as the specific capacitance of graphene. T-GR, with a capacitance of 354.1 Fg(-1) at 5 mVs(-1) and 264 Fg(-1) at 100 mVs(-1), exhibits excellent performance as a supercapacitor.

Matched MeSH terms: Ethylene Glycol
Fulltext Heat transfer enhancement in free convection flow of CNTs Maxwell nanofluids with four different types of molecular liquids

Aman S, Khan I, Ismail Z, Salleh MZ, Al-Mdallal QM

Sci Rep, 2017 05 26;7(1):2445.
PMID: 28550289 DOI: 10.1038/s41598-017-01358-3

This article investigates heat transfer enhancement in free convection flow of Maxwell nanofluids with carbon nanotubes (CNTs) over a vertically static plate with constant wall temperature. Two kinds of CNTs i.e. single walls carbon nanotubes (SWCNTs) and multiple walls carbon nanotubes (MWCNTs) are suspended in four different types of base liquids (Kerosene oil, Engine oil, water and ethylene glycol). Kerosene oil-based nanofluids are given a special consideration due to their higher thermal conductivities, unique properties and applications. The problem is modelled in terms of PDE's with initial and boundary conditions. Some relevant non-dimensional variables are inserted in order to transmute the governing problem into dimensionless form. The resulting problem is solved via Laplace transform technique and exact solutions for velocity, shear stress and temperature are acquired. These solutions are significantly controlled by the variations of parameters including the relaxation time, Prandtl number, Grashof number and nanoparticles volume fraction. Velocity and temperature increases with elevation in Grashof number while Shear stress minimizes with increasing Maxwell parameter. A comparison between SWCNTs and MWCNTs in each case is made. Moreover, a graph showing the comparison amongst four different types of nanofluids for both CNTs is also plotted.

Matched MeSH terms: Ethylene Glycol
Blends of LNR with unsaturated polyester resin from recycled PET: comparison of mechanical properties and morphological analysis with the optimum blend by commercial resin

Siti Farhana Hisham, Ishak Ahmad, Rusli Daik, Anita Ramli

Sains Malaysiana, 2011;40:1179-1186.

In this study, poly(ethylene terephthalate) (PET) wastes bottle was recycled by glycolysis process using ethylene glycol. The unsaturated polyester resin (UPR) was then prepared by reacting the glycolysed product with maleic anhydride. The blend of UPR based on recycled PET wastes with liquid natural rubber (LNR) was carried out by varying the amount of LNR from 0 to 7.5 wt%. Mechanical tests such as tensile and impact were conducted to investigate the effects of LNR on the mechanical properties. Scanning Electron Microscopy (SEM) was used to analyze the morphology of the breaking area resulted from the tensile tests on the UPR and blend samples. From the results, the blend of 2.5 wt% LNR in UPR based recycled PET wastes achieved the highest strength in the mechanical properties and showed a well dispersed of elastomer particles in the sample morphology compared to other blends concentrations. This blend sample was then compared to the optimum blend of LNR with commercial resin through the glass transition temperature value Tg, mechanical strength and morphology properties. The comparison study showed that the Tg for UPR based recycled PET was higher than the value represented from commercial resin due to the degree of crystalinity in the molecular structure of the materials. LNR was found to be an effective impact modifier which gave a greater improvement in UPR from recycled PET wastes structure but not to the commercial one which needs 5% LNR to achieve the optimum properties. Thus, the compatibility between the UP resin based recycled PET and LNR was much better than with the commercial resin.

Matched MeSH terms: Ethylene Glycol
Effect of Various Polyols on the Acid-Denatured States of Champedak Galactose-Binding Lectin

Kameel NIA, Shuib AS, Tayyab S

Protein Pept Lett, 2018;25(3):314-324.
PMID: 29384048 DOI: 10.2174/0929866525666180130155007

BACKGROUND: Champedak galactose-binding (CGB) lectin is a tetrameric protein with noncovalently bound monomers, isolated from Artocarpus integer fruit seeds. We had previously reported existence of a structured monomer and an unfolded monomer of CGB lectin at pH 2.5 and pH 1.5, respectively. Polyols are known to induce significant refolding in denatured proteins and stabilize proteins against environmental stresses. Studies on the effect of various polyols on the acid-denatured states of CGB lectin are lacking.
OBJECTIVE: The objective of this study was to investigate the effects of four different polyols, namely, ethylene glycol, erythritol, xylitol and sorbitol on the acid-denatured states of CGB lectin.
METHODS: CGB lectin was subjected to acid denaturation at pH 2.5 and pH 1.5, both in the absence and presence of 30% (w/v) polyols, i.e. ethylene glycol, erythritol, xylitol and sorbitol. Thermal denaturation of the acid-denatured states was also studied in the absence and presence of these polyols. Different spectroscopic probes such as tryptophan fluorescence, ANS fluorescence and far-UV CD spectral signal were used to monitor structural changes in the acid-denatured states of CGB lectin in the presence of polyols.
RESULTS: Presence of erythritol, xylitol and sorbitol in the incubation mixture was found to stabilize the lectin at both pH 2.5 and pH 1.5, as evident from the burial of the hydrophobic clusters and decreased polarity around Trp residues. These polyols also stabilized the acid-denatured states of CGB lectin against thermal denaturation by shifting the thermal transition curves towards higher temperatures. Exposure of the acid-denatured states of CGB lectin, obtained at pH 2.5 and pH 1.5 to 61°C and 51°C, respectively, induced formation of non-native β-structures, compared to that present at 25°C, and this phenomenon was significantly suppressed in the presence of these polyols. Based on the spectral data, both sorbitol and erythritol appeared to exude better stabilizing effect. On the other hand, ethylene glycol was shown to destabilize the aciddenatured states of CGB lectin.
CONCLUSION: Thermal stabilization of the lectin was noticed in the presence of erythritol, xylitol and sorbitol at both pH 2.5 and pH 1.5. These polyols also stabilize the secondary and tertiary structures of the acid-denatured CGB lectin at 25°C. Ethylene glycol was proved to be a destabilizer of the acid-denatured CGB lectin.

Matched MeSH terms: Ethylene Glycol/chemistry*
Fulltext Simulation and optimisation of Bioethanol purification using extractive distillation with additive solvent

Anisuzzaman, S.M., Krishnaiah, D., Bono, A., Lahin, F.A., Suali, E., Zuyyin, I.A.Z.

Pertanika Journal of Science & Technology, 2018;26(2):707-718.
MyJurnal

In this study, simulation and optimisation of the purification of bioethanol from an azeotropic mixture was done using the Aspen HYSYS and the Response Surface Methodology (RSM), respectively, to achieve an acceptable bioethanol content with minimal energy use. The objective of this study is to develop the simulation process of bioethanol production from a fermentation effluent. Additionally, the effects of parameters such as solvent temperature, number of entrainer feed stage, mass flow rate and third components of the process for production of bioethanol were studied. As bioethanol is a product of biofuel production, the main challenge facing bioethanol production is the separation of high purity ethanol. However, the separation of ethanol and water can be achieved with the addition of a suitable solvent such as 1,3-butylene glycol (13C4Diol), mixture 13C4Diol and ethylene glycol (EGlycol) and mixture 13C4Diol and glycol ethyl ether (DEG) in the extractive distillation process. For the 13C4Diol mixture, the temperature of entrainer is 90oC with 1500 kg/hr of entrainer rate, while the number of entrainer feed stage is one. The optimum conditions for mixture 13C4Diol and EGlycol require a temperature of entrainer of 90.77oC with an entrainer rate of 1500 kg/hr, while the number of entrainer feed stage is one. Lastly, for optimum conditions for the mixture 13C4Diol and DEG, the temperature of entrainer should be 90oC with an entrainer rate of 1564.04 kg/hr, while the number of entrainer feed stage is one. This study shows that process simulation and optimisation can enhance the removal of water from an azeotropic mixture.

Matched MeSH terms: Ethylene Glycol
Functionalized fluorescent terephthalate monomers and their attempted polyester formation

Choo YSL, Giamberini M, Antonio J, Waddell PG, Benniston AC

Org Biomol Chem, 2020 Nov 04;18(42):8735-8745.
PMID: 33094783 DOI: 10.1039/d0ob01533d

The reaction of diethyl 2,5-bis(tert-butyl)phenoxy-3,6-dihydroxyterephthalate (1) with tetraethylene glycol di(p-toluenesulfonate) under high-dilution conditions afforded several isolated products. Two products were identified as macrocycles with one being the 1 + 1 crown ether derivative 3 (10% yield), and the second being the 2 + 2 crown ether compound D3 (19% yield). The X-ray structure for 3 was determined with the asymmetric unit observed to comprise half of the molecule. The small crown ether ring of 3 interacts with K+ or H+ ions in MeOH, but binding is weak and the macrocyclic cavity is too small to fully encapsulate the K+ ion. Transesterification of compounds 1, its methylated version 2 and 3 with diols such as ethylene glycol or 1,4-butandiol produced monomers (M1-M3) which were reacted with terephthaloyl chloride. Short oligomers were produced (PolyM1-PolyM3) rather than extensive polymeric materials and all displayed solid state fluorescence. The absorption and fluorescence properties of M1-M2 and their polymers can be related to subtle structural changes. The Stokes shift for M2 of 15 627 cm-1 in DCM is one of the largest observed for a simple organic chromophore in fluid solution.

Matched MeSH terms: Polyethylene Glycols; Ethylene Glycol
Formation of grassy TiO2 nanotube thin film by anodisation in peroxide electrolyte for Cr(VI) removal under ultraviolet radiation

Taib MAA, Alias N, Jaafar M, Razak KA, Tan WK, Shahbudin IP, et al.

Nanotechnology, 2020 Oct 23;31(43):435605.
PMID: 32640434 DOI: 10.1088/1361-6528/aba3d8

Arrays of TiO2 nanotubes (TiO2 NTs) with grassy surfaces were observed on titanium foil anodised at 60 V in fluorinated ethylene glycol (EG) with added hydrogen peroxide (H2O2). The grassy surface was generated by the chemical etching and dissolution of the surface of the TiO2 NTs walls, which was accelerated by the temperature increase on the addition of H2O2 . Upon annealing at 600 °C, the grassy part of the TiO2 NTs was found to consist of mostly anatase TiO2 whereas the bottom part of the anodic oxide comprised a mixture of anatase and rutile TiO2. The TiO2 NTs were then used to reduce hexavalent chromium (Cr(VI)) under ultraviolet radiation. They exhibited a rather efficient photocatalytic effect, with 100% removal of Cr(VI) after 30 min of irradiation. The fast removal of Cr(VI) was due to the anatase dominance at the grassy part of the TiO2 NTs as well as the higher surface area the structure may have. This work provides a novel insight into the photocatalytic reduction of Cr(VI) on grassy anatase TiO2 NTs.

Matched MeSH terms: Ethylene Glycol
Fulltext Energy Transfer in Mixed Convection MHD Flow of Nanofluid Containing Different Shapes of Nanoparticles in a Channel Filled with Saturated Porous Medium

Aaiza G, Khan I, Shafie S

Nanoscale Res Lett, 2015 Dec;10(1):490.
PMID: 26698873 DOI: 10.1186/s11671-015-1144-4

Energy transfer in mixed convection unsteady magnetohydrodynamic (MHD) flow of an incompressible nanofluid inside a channel filled with saturated porous medium is investigated. The channel with non-uniform walls temperature is taken in a vertical direction under the influence of a transverse magnetic field. Based on the physical boundary conditions, three different flow situations are discussed. The problem is modelled in terms of partial differential equations with physical boundary conditions. Four different shapes of nanoparticles of equal volume fraction are used in conventional base fluids, ethylene glycol (EG) (C 2 H 6 O 2 ) and water (H 2 O). Solutions for velocity and temperature are obtained discussed graphically in various plots. It is found that viscosity and thermal conductivity are the most prominent parameters responsible for different results of velocity and temperature. Due to higher viscosity and thermal conductivity, C 2 H 6 O 2 is regarded as better convectional base fluid compared to H 2 O.

Matched MeSH terms: Ethylene Glycol
Fulltext Fabrication, characterization, and thermal property evaluation of silver nanofluids

Noroozi M, Radiman S, Zakaria A, Soltaninejad S

Nanoscale Res Lett, 2014;9(1):645.
PMID: 25489293 DOI: 10.1186/1556-276X-9-645

Silver nanoparticles were successfully prepared in two different solvents using a microwave heating technique, with various irradiation times. The silver nanoparticles were dispersed in polar liquids (distilled water and ethylene glycol) without any other reducing agent, in the presence of the stabilizer polyvinylpyrrolidone (PVP). The optical properties, thermal properties, and morphology of the synthesized silver particles were characterized using ultraviolet-visible spectroscopy, photopyroelectric technique, and transmission electron microscopy. It was found that for the both solvents, the effect of microwave irradiation was mainly on the particles distribution, rather than the size, which enabled to make stable and homogeneous silver nanofluids. The individual spherical nanostructure of self-assembled nanoparticles has been formed during microwave irradiation. Ethylene glycol solution, due to its special properties, such as high dielectric loss, high molecular weight, and high boiling point, can serve as a good solvent for microwave heating and is found to be a more suitable medium than the distilled water. A photopyroelectric technique was carried out to measure thermal diffusivity of the samples. The precision and accuracy of this technique was established by comparing the measured thermal diffusivity of the distilled water and ethylene glycol with values reported in the literature. The thermal diffusivity ratio of the silver nanofluids increased up to 1.15 and 1.25 for distilled water and ethylene glycol, respectively.

Matched MeSH terms: Ethylene Glycol
Fulltext InSitu Anodization of WO₃-Decorated TiO₂ Nanotube Arrays for Efficient Mercury Removal

Lee WH, Lai CW, Hamid SBA

Materials (Basel), 2015 Aug 28;8(9):5702-5714.
PMID: 28793530 DOI: 10.3390/ma8095270

WO₃-decorated TiO₂ nanotube arrays were successfully synthesized using an in situ anodization method in ethylene glycol electrolyte with dissolved H₂O₂ and ammonium fluoride in amounts ranging from 0 to 0.5 wt %. Anodization was carried out at a voltage of 40 V for a duration of 60 min. By using the less stable tungsten as the cathode material instead of the conventionally used platinum electrode, tungsten will form dissolved ions (W(6+)) in the electrolyte which will then move toward the titanium foil and form a coherent deposit on the titanium foil. The fluoride ion content was controlled to determine the optimum chemical dissolution rate of TiO₂ during anodization to produce a uniform nanotubular structure of TiO₂ film. Nanotube arrays were then characterized using FESEM, EDAX, XRD, as well as Raman spectroscopy. Based on the FESEM images obtained, nanotube arrays with an average pore diameter of up to 65 nm and a length of 1.8 µm were produced. The tungsten element in the samples was confirmed by EDAX results which showed varying tungsten content from 0.22 to 2.30 at%. XRD and Raman results showed the anatase phase of TiO₂ after calcination at 400 °C for 4 h in air atmosphere. The mercury removal efficiency of the nanotube arrays was investigated by photoirradiating samples dipped in mercury chloride solution with TUV (Tube ultraviolet) 96W UV-B Germicidal light. The nanotubes with the highest aspect ratio (15.9) and geometric surface area factor (92.0) exhibited the best mercury removal performance due to a larger active surface area, which enables more Hg(2+) to adsorb onto the catalyst surface to undergo reduction to Hg⁰. The incorporation of WO₃ species onto TiO₂ nanotubes also improved the mercury removal performance due to improved charge separation and decreased charge carrier recombination because of the charge transfer from the conduction band of TiO₂ to the conduction band of WO₃.

Matched MeSH terms: Ethylene Glycol
Fulltext Free standing zirconia nanotubes formation and their photocatalytic properties

Syahriza Ismail, Nurul Izza Soaid, Suriyati Mohamed Ansari, Nurulhuda Bashirom, Monna Rozana, Tan, Wai Kian, et al.

Malaysian Journal of Microscopy, 2016;12(1):20-23.
MyJurnal

In the formation of ZrO2 (zirconia) nanotubes (ZNTs) by anodisation of zirconium, a balance between chemical etching at the surface of the nanotubes and inward growth inside the nanotubes is required. This can be achieved by using fluorinated organic electrolyte like ethylene glycol with the addition of small volume of oxidant. In this work, carbonate was selected as the oxidant and NH4F as the source of fluoride for chemical etching process. Two sets of electrolytes were studied EG/fluoride/Na2CO3 and EG/fluoride/K2CO3. It appears that in the presence of carbonate evolution of gas at the anode during the anodisation process was rather severe. The gas which is likely to be CO2 was found to weaken the adherence between the oxide film with the underlying Zr foil. This induced the formation of free standing ZNTs. High Resolution Transmission Electron Microscope (HRTEM) was used to investigate the crystallinity of the nanotubes where the majority crystal phase of ZNTs was tetragonal/cubic. The ZNTs were used as photocatalysts to oxidize methyl orange dye.

Matched MeSH terms: Ethylene Glycol
Measurement system analysis on the external standard using an azeotropic mixture of ethylene glycol and detailed uncertainties

Ahmad Hazmi AS, Abd Maurad Z, Mohd Noor MA, Nek Mat Din NSM, Idris Z

J Sep Sci, 2021 Apr;44(7):1471-1481.
PMID: 33522105 DOI: 10.1002/jssc.202000929

Ethylene glycol is a super commodity chemical and it has vital roles in various applications. Its co-production with other chemicals, such as ethylene carbonate and glycerol carbonate, has promised cheaper production cost. Its quantification presents a challenge as its contaminants, such as ethylene carbonate, produce a signal-reducing effect in flame ionized detector. The aim of this study is to evaluate external standard to quantify the composition of glycol mixture. Measurement system analysis was employed on the external standard method. Reliability of the external standard is statistically significant with low p-values, excellent capability indices, and high F-values. The external standard is found to have remarkable precision and trueness as both capability indices are mirroring each other. Furthermore, the capability analysis has a strong correlation with quality measurement. Based on capability indices, the limit of detection is recommended at S/N = 25 and the limit of quantification is recommended at S/N = 100 for a reliable measurement. A high degree of reliability is achieved coherently as almost all uncertainties of coefficients of variations are less than 5%. The established method was validated and successfully applied to glycol mixture at azeotropic distillation pilot plant.

Matched MeSH terms: Ethylene Glycol
Controlled Synthesis of Well-Aligned and Highly Ordered TiO₂ Nanotubes Without Bundling for Enhanced Solar-Powered Photoelectrochemical Responses

Lai CW, Lau KS, Chou PM

J Nanosci Nanotechnol, 2019 Dec 01;19(12):7934-7942.
PMID: 31196312 DOI: 10.1166/jnn.2019.16777

Using solar-powered water electrolysis systems for hydrogen generation is a key decision for the development of a sustainable hydrogen economy. A facile approach is presented in the present investigation to improve the solar-powered photoelectrochemical performance of water electrolysis systems by synthesising well-aligned and highly ordered TiO₂ nanotube films without bundling through the electrochemical anodisation technique. Herein, geometrical calculations were conducted for all synthesised TiO₂ nanotubes, and determination of the aspect ratio (AR) and geometric surface area factor (G) was achieved. On the basis of the collected data, well-aligned TiO₂ nanotubes with an AR of approximately 60 and G of approximately 400 m² ·g-1 were successfully formed in an electrolyte mixture of ethylene glycol with 0.3 wt% NH4F and 5 wt% H₂O₂ at 40 V for 60 min. The nanotubes were subsequently annealed at 400 °C to form anatase-phase TiO₂ nanotube films. The resultant well-aligned and highly ordered TiO₂ nanotube films exhibited a photocurrent density of 1.5 mA · cm-2 due to a large number of photo-induced electrons moving along the tube axis and perpendicular to the Ti substrate, which greatly reduces interfacial recombination losses.

Matched MeSH terms: Ethylene Glycol
Rapid Nucleation of Reduced Graphene Oxide-Supported Palladium Electrocatalysts for Methanol Oxidation Reaction

Ng JC, Tan CY, Ong BH, Matsuda A, Basirun WJ, Tan WK, et al.

J Nanosci Nanotechnol, 2019 Nov 01;19(11):7236-7243.
PMID: 31039881 DOI: 10.1166/jnn.2019.16717

Small sized electrocatalysts, which can be obtained by rapid nucleation and high supersaturation are imperative for outstanding methanol oxidation reaction (MOR). Conventional microwave synthesis processes of electrocatalysts include ultrasonication, stirring, pH adjustment, and microwave irradiation of the precursor mixture. Ethylene glycol (EG), which serves as a reductant and solvent was added during the ultrasonication or stirring stage. However, this step and pH adjustment resulted in unintended multi-stage gradual nucleation. In this study, the microwave reduction approach was used to induce rapid nucleation and high supersaturation in order to fabricate small-sized reduced graphene oxide-supported palladium (Pd/rGO) electrocatalysts via the delayed addition of EG, elimination of the pH adjustment step, addition of sodium carbonate (Na₂CO₃), prior microwave irradiation of the EG mixed with Na₂CO₃, and addition of room temperature precursor mixture. Besides its role as a second reducing agent, the addition of Na₂CO₃ was primarily intended to generate an alkaline condition, which is essential for the high-performance of electrocatalysts. Moreover, the microwave irradiation of the EG and Na₂CO₃ mixture generated highly reactive free radicals that facilitate rapid nucleation. Meanwhile, the room temperature precursor mixture increased supersaturation. Results showed improved electrochemically active surface area (78.97 m² g-1, 23.79% larger), MOR (434.49 mA mg-1, 37.96% higher) and stability.

Matched MeSH terms: Ethylene Glycol
Photoelectrochemical behaviour of uniform growth TiO2 nanotubes via bubble blowing synthesised in ethylene glycol with hydrogen peroxide

Lai CW, Sreekantan S, Lockman Z

J Nanosci Nanotechnol, 2012 May;12(5):4057-66.
PMID: 22852347

Uniformly sized TiO2 nanotubes with high aspect ratios were synthesised on a large substrate (100 mm x 100 mm) via the bubbling system through anodisation of Ti in ethylene glycol containing 5 wt% NH4F and 5 wt% H2O2. The benefits of bubbling system in producing uniformly sized TiO2 nanotubes throughout the Ti foil are illustrated. Moreover, the effects of applied voltage and fluoride content on the resulting nanotubes were also considered. Such uniform sized TiO2 nanotubes are a key to produce hydrogen efficiently using PEC cell. The results show higher photocurrent responses for the high aspect ratio, uniform TiO2 nanotubes because of excellent interfacial electron transfer.

Matched MeSH terms: Ethylene Glycol
Visible light photoelectrochemical performance of W-loaded TiO2 nanotube arrays: structural properties

Lai CW, Sreekantan S

J Nanosci Nanotechnol, 2012 Apr;12(4):3170-4.
PMID: 22849082

Well aligned TiO2 nanotubes were successfully synthesized by anodization of Ti foil at 60 V in a fluorinated bath comprised of ethylene glycol with 5 wt% of NH4F and 5 wt% of H2O2. In order to enhance the visible light absorption and photoelectrochemical response of pure TiO2 nanotube arrays, a mixed oxide system (W-TiO2) was investigated. W-TiO2 nanotube arrays were prepared using radio-frequency (RF) sputtering to incorporate the W into the lattice of TiO2 nanotube arrays. The W atoms occupy the substitutional position within the vacancies of TiO2 nanotube arrays. The as-anodized TiO2 is amorphous in nature while the annealed TiO2 is anatase phase. The mixed oxide (W-TiO2) system in suitable TiO2 phase plays important roles in efficient electron transfers due to the reduction in electron-hole recombination. In this article, the effect of the sputtered W into the as-anodized/annealed TiO2 nanotube arrays on the photoelectrochemical response was presented.

Matched MeSH terms: Ethylene Glycol
Enhanced removal of lead from contaminated soil by polyol-based deep eutectic solvents and saponin

Mukhopadhyay S, Mukherjee S, Hayyan A, Hayyan M, Hashim MA, Sen Gupta B

J Contam Hydrol, 2016 Nov;194:17-23.
PMID: 27697607 DOI: 10.1016/j.jconhyd.2016.09.007

Deep eutectic solvents (DESs) are a class of green solvents analogous to ionic liquids, but less costly and easier to prepare. The objective of this study is to remove lead (Pb) from a contaminated soil by using polyol based DESs mixed with a natural surfactant saponin for the first time. The DESs used in this study were prepared by mixing a quaternary ammonium salt choline chloride with polyols e.g. glycerol and ethylene glycol. A natural surfactant saponin obtained from soapnut fruit pericarp, was mixed with DESs to boost their efficiency. The DESs on their own did not perform satisfactory due to higher pH; however, they improved the performance of soapnut by up to 100%. Pb removal from contaminated soil using mixture of 40% DES-Gly and 1% saponin and mixture of 10% DES-Gly and 2% saponin were above 72% XRD and SEM studies did not detect any major corrosion in the soil texture. The environmental friendliness of both DESs and saponin and their affordable costs merit thorough investigation of their potential as soil washing agents.

Matched MeSH terms: Ethylene Glycol/chemistry

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