Wide Range Of Liquids Research Articles

Pyrrolidinium-Based Ionic Liquids as Advanced Non-Aqueous Electrolytes for Safer Next Generation Lithium Batteries

In the current context of increasing energy demand, ionic liquids (ILs) are presented as possible candidates to replace conventional electrolytes and to develop more efficient energy storage devices. The IL 1-Methyl-1-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide has been selected for this work, due to the good thermal and chemical stabilities and good electrochemical performance of the pyrrolidinium cation based ILs. Binary mixtures of this IL and lithium salt with the same anion, [TFSI], have been prepared with the aim of assessing them, as possible electrolytes for lithium batteries. These mixtures were thermally and electrochemically characterised through DSC and dielectric spectroscopy studies. The ionic conductivity decreases as the salt concentration increases, finding values ranging between 0.4 S/m and 0.1 S/m at room temperature. Additionally, a wide liquid range was found for the mixtures, which would reduce or even eliminate some of the most common problems of current electrolytes, such as their crystallisation at low temperatures and flammability. Finally, the toxicity of pure IL and the intermediate salt concentration was also evaluated in terms of the bioluminescence inhibition of the Alivibrio Fischeri bacteria, observing that, although the toxicity increases with the salt addition, both samples can be classified as practically harmless.

Facile fabrication of super-slippery and transparent glass with anti-fogging and self-cleaning characteristics

The present work reports a facile and effective approach for developing slippery liquid-infused porous surface (SLIPS) nanoporous glass. Glass was chemically etched using KOH solution followed by silanization and silicone oil coating using vapour deposition at different temperatures. SLIPS glass showed high contact angle ∼ 115⁰ compared to nascent glass (∼40⁰), low hysteresis (<5°). The sample showed sliding angle < 5⁰ against wide range of liquids with surface tension as low as 28 mN/m. The super-slippery behaviour was coupled with uncompromised transparency (>90 %) and enhanced oil retention owing to the presence of nanopores acting as reservoirs. The SLIPS glass maintained slippery nature (SA < 5⁰) during exposure to ultrasonic vibrations, multiple cloth wiping cycles and multiple high-velocity droplet impacts. The slippery glass showed exquisite combination of properties involving anti-fogging, self-cleaning and anti-staining, with widespread applications.

Development of a Molecular Dynamics Model to Assess the Possibility of Type II/III Porous Liquid Formation

The study of porous liquids (PLs) using molecular dynamics (MD) simulation is one of the most interesting and attractive research topics. The possibility of creating permanent porosity in a solvent and increasing its adsorption capacity is very practical. The purpose of the present study is to examine how an MD model can be developed to evaluate the possibility of PL formation. Additionally, the validation of the model was conducted by simulations using two metal–organic frameworks (MOFs) including zeolitic imidazolate framework-8 (ZIF-8) and Hong Kong University of Science and Technology-1 (HKUST-1) as porogens and water (H2O) and triethylene glycol (TEG) as solvents. The results revealed that H2O and TEG are incapable of penetrating the ZIF-8 pores due to their small size and unfavorable thermodynamics; however, both solvents easily penetrate through the large HKUST-1 pores. These observations aligned with findings from experimental literature studies, thus confirming the validity of the model. In order to expand the model’s scope, the developed model was used to assess the possibility of PL formation using ZIF-8 and HKUST-1 with different pore and window sizes and shapes, and a wide range of hydrocarbon liquids with different molecular sizes and shapes as solvents. It was found that ZIF-8 can form PLs with a more extensive range of sterically hindered solvents due to its smaller apertures and incompatible shape. In addition, only a few solvents (e.g., n-pentane, benzene, 1,3,5-trimethylbenzene, 1,3,5-triisopropylcyclohexane, and 1,3,5-triisopropylbenzene) can partially penetrate its ZIF-8 pores without steric hindrance. These privileged solvents typically have an aspect ratio far from 1, indicating a more elongated shape, and/or more linear branches. In contrast, HKUST-1, which has larger apertures and a compatible shape, allows for complete penetration of specific solvents (e.g., benzene, iso-octane, n-pentane), thereby preventing PL formation with such combinations. In addition, cyclohexane has the ability to partially penetrate the pores of HKUST-1. Therefore, in addition to the size of the solvent molecule, one of the most important properties for penetration is the compatibility of the shape of the porogen pore window with the shape of the solvent molecule. This research provides important new information on how PLs come to be by illuminating the role that solvent molecules and porogen play in promoting penetration and, in the end, impacting the process of PL formation.

Benzyl-methylbenzyl-benzene: Improving hydrogen storage and release performance of dibenzyltoluene based liquid organic hydrogen carrier

Liquid organic hydrogen carrier (LOHC) technology enables the safe, easy, and cost-effective storage and transportation of large quantities of hydrogen using inexpensive and mass-produced compounds. The LOHC materials play a crucial role in hydrogen storage capacity, reaction kinetics, reaction temperature, and reversibility. However, the development and optimization of LOHC materials is limited due to using of mass-produced materials for bulk hydrogen logistics. Herein, we propose a molecular engineering approach to overcome the limitations of commercial dibenzyltoluene (DBT)-based LOHC systems, considered one of the most promising LOHC materials based on the heat transfer oil, Marlotherm SH (MSH), owing to its superior physical properties (wide liquid range, and non-flammable properties), low price, and low toxicity. We devised a new chemical structure, benzyl-methylbenzyl-benzene (BMB), with highly improved dehydrogenation/hydrogenation performance achieved by rearranging the methyl group of DBT to overcome the limitations of slow reaction kinetics in terms of its chemical structure. The BMB exhibits a 150 % faster hydrogenation than MSH at 150 °C, and it releases 170 % more hydrogen compared to DBT at 270 °C. In addition, we analyzed the dehydrogenation/hydrogenation pathways according to the structures of DBT and BMB. Furthermore, we found that BMB (27 %) is inevitably generated in the MSH synthesis process alongside DBT (73 %). Based on this, we propose a streamlined and sustainable engineered method for improved MSH material manufacturing with a high BMB ratio (∼70 %). The scientific findings provide a fundamental understanding of DBT-based LOHC systems and new insights into the design of novel LOHC candidates.

Influence of repulsion on entropy scaling and density scaling of monatomic fluids.

Entropy scaling is applied to the shear viscosity, self-diffusion coefficient, and thermal conductivity of simple monatomic fluids. An extensive molecular dynamics simulation series is performed to obtain these transport properties and the residual entropy of three potential model classes with variable repulsive exponents: n, 6 Mie (n = 9, 12, 15, and 18), Buckingham's exponential-six (α = 12, 14, 18, and 30), and Tang-Toennies (αT = 4.051, 4.275, and 4.600). A wide range of liquid and supercritical gas- and liquid-like states is covered with a total of 1120 state points. Comparisons to equations of state, literature data, and transport property correlations are made. Although the absolute transport property values within a given potential model class may strongly depend on the repulsive exponent, it is found that the repulsive steepness plays a negligible role when entropy scaling is applied. Hence, the plus-scaled transport properties of n, 6 Mie, exponential-six, and Tang-Toennies fluids lie basically on one master curve, which closely corresponds with entropy scaling correlations for the Lennard-Jones fluid. This trend is confirmed by literature data of n, 6 Mie, and exponential-six fluids. Furthermore, entropy scaling holds for state points where the Pearson correlation coefficient R is well below 0.9. The condition R > 0.9 for strongly correlating liquids is thus not necessary for the successful application of entropy scaling, pointing out that isomorph theory may be a part of a more general framework that is behind the success of entropy scaling. Density scaling reveals a strong influence of the repulsive exponent on this particular approach.

Evaluation of factors causing lateral migration of light non-aqueous phase liquids (LNAPLs) in onshore oil spill accidents.

Contamination of groundwater by harmful substances poses significant risks to both drinking water sources and aquatic ecosystems, making it a critical environmental concern. Most on-land spill events release organic molecules known as light non-aqueous phase liquids (LNAPLs), which then seep into the ground. Due to their low density and organic composition, they tend to float as they reach the water table. LNAPLs encompass a wide range of non-aqueous phase liquids, including various petroleum products, and can, over time, develop carcinogenic chemicals in water. However, due to frequent changes in hydraulic head, the confinement may fail to contain them, causing them to extend outward. When it contaminates water wells, people cannot reliably consume the water. The removal of dangerous contaminants from groundwater aquifers is made more challenging by LNAPLs. It is imperative to analyze the mechanisms governing LNAPL migration. As a response to this need and the associated dispersion of contaminants into adjacent aquifers, we have conducted a comprehensive qualitative literature review encompassing the years 2000-2022. Groundwater variability, soil structure, and precipitation have been identified as the three primary influential factors, ranked in the following order of significance. The rate of migration is shown to rise dramatically in response to changes in groundwater levels. Different saturation zones and confinement have a major effect on the lateral migration velocity. When the various saturation zones reach a balance, LNAPLs will stop moving. Although higher confinement slows the rate of lateral migration, it speeds up vertical migration. Beyond this, the lateral or vertical movement is also influenced by differences in the permeability of soil strata. Reduced mobility and tighter containment are the outcomes of migrating through fine-grained, low-porosity sand. The gaseous and liquid phases of LNAPLs move more quickly through coarse-grained soils. Due to the complexities and uncertainties associated with LNAPL behavior, accurately foreseeing the future spread of LNAPLs can be challenging. Although studies have utilized modeling techniques to simulate and predict LNAPL migration, the inherent complexities and uncertainties in the subsurface environment make it difficult to precisely predict the extent of LNAPL spread in the future. The granular soil structure considerably affects the porosity and pore pressure.

Identification of hazardous organic substances for fire investigation with portable GC-MS

First responders employ field-portable gas chromatograph - mass spectrometers (GC-MS) to chemically evaluate compounds that may be drugs, explosives, poisonous industrial chemicals or materials, chemical warfare agents, or other dangerous substances. They can measure a wide range of gases, volatile and semi-volatile liquids, and some solids' vapor emissions. Field-portable instrumentation is easily deployable to identify hazardous substances in-situ during an incident response. Using this strategy, real-time targeted risk mitigation and management decisions may be taken to put stronger safety precautions in place and help resolve incidents. The portable GC-MS was able to provide preliminary analytical data on the volatile organic chemicals present in air samples taken from both active and extinguished fires, according to controlled field testing.

New stachydrine-derived ionic liquids enable the formation of robust cathode electrolyte interphase for improving the performance of LiFePO4 battery

In the present study, several new stachydrine-based room temperature ionic liquids ([Cn-Sta] ILs, n = 2, 3, 4 or 5) are prepared, characterized and applied as an electrolyte additive to significantly improve LiFePO4 battery performance. The Sta-based ILs are structurally homologous with the popular pyrrolidinium ILs combining a chiral ester group close to the N+ cationic center, leading to low symmetry for the absence of cold crystallization, a wide liquid range from about −60 °C (glass transition temperature) to 320 °C (thermal decomposition temperature) and a decent electrochemical stability window (∼4.5 V). These ILs are ready to decompose on the surface of LiFePO4 particles to form LiF-rich and robust cathode electrolyte interphase (CEI) passivation layers, according to an aggregate study of electrochemical and morphological evidence. As a result, the ILs are used as an efficient CEI-forming additive to improve the LiFePO4 battery performance, namely higher capacity and cyclic capacity retention, better high-current rate performance and lower initial resistance.

Redefine the existence form and function of water in potassium carbonate-based deep eutectic electrolyte

Here, we prepared a green and novel deep eutectic electrolyte (DEE) consisting of potassium carbonate (PC) and ethylene glycol (EG). The formation mechanism and microstructure of deep eutectic solvent (DES) were studied by FTIR, 1H NMR and molecular dynamics simulation. And physicochemical properties of DES were further investigated by thermogravimetric analysis, differential thermal scanning analysis and conductivity measurement. The influence of H2O on the microstructure, physical properties and electrochemical properties of PC-EG electrolyte were systematically investigated. The results showed that PC-EG-20 where PC:EG molar ratio was 1:20 had a wide liquid range and the highest conductivity. The supercapacitor assembled from PC-EG-20 and activated carbon had a voltage window of 2.0 V, a specific capacitance of 190 F g−1 and an energy density of 23.89 Wh kg−1. Especially, the capacitor also exhibited a wide liquid range from −50 to 100 °C. Although the addition of H2O may reduce the electrochemical stability window of DEE, it can improve ionic conductivity and decrease viscosity, thereby improving capacitance and rate performance. This work may promote understanding and extend the application of DEE in supercapacitors.

"USE OF OIL-WATER EMULSION IN SWIRL BURNERS "

Efficient combustion of unconventional fuels has come to the forefront of research in recent years by scientists in many countries due to the accelerating depletion of fossil fuels. With the development of computer technology, more and more attention is being paid to modelling using a wide range of specialised software at the expense of more accurate experimental studies due to expensive laboratory equipment and consumables. In this paper a brief review of experimental studies related to preparation and combustion of water-oil emulsion (WOE) with explanation of the process of micro explosion of fuel droplets and dependence of combustion efficiency on the percentage of water in the fuel is presented. An experiment on combustion of WOE using a patented innovative burner for a wide range of liquid and gaseous fuels was conducted. Based on a previously published article describing a wave disperser made by the authors, a mixture of fuel oil with water concentrations of 5 %, 10 %, 15 % and 20 % in WOE and once pure fuel oil was prepared and burned. The results of the analysis of the harmful emissions data show a decrease as the moisture content of the fuel increases. The most optimal moisture content as measured by the heat release rate of the water-oil emulsion is at 20 %.

1,3,5-Trifluorobenzene endorsed EC-free electrolyte for high-voltage and wide-temperature lithium-ion batteries

Ethylene carbonate (EC) is susceptible to the aggressive chemistry of nickel-rich cathodes, making it undesirable for high-voltage lithium-ion batteries (LIBs). The arbitrary elimination of EC leads to better oxidative tolerance but always incurs interfacial degradation and electrolyte decomposition. Herein, an EC-free electrolyte is deliberately developed based on gradient solvation by pairing solvation-protection agent (1,3,5-trifluorobenzene, F3B) with propylene carbonate (PC)/methyl ethyl carbonate (EMC) formulation. F3B keeps out of inner coordination shell but decomposes preferentially to construct robust interphase, inhibiting solvent decomposition and electrode corrosion. Thereby, the optimized electrolyte (1.1 M) with wide liquid range (−70–77 °C) conveys decent interfacial compatibility and high-voltage stability (4.6 V for LiNi0.6Mn0.2Co0.2O2, NCM622), qualifying reliable operation of practical NCM/graphite pouch cell (81.1% capacity retention over 600 cycles at 0.5 C). The solvation preservation and interface protection from F3B blaze a new avenue for developing high-voltage electrolytes in next-generation LIBs.

Choline chloride-water mixtures as new generation of green solvents: A comprehensive physico-chemical study

Natural deep eutectic solvents (NADES) are an increasingly appreciated class of mixtures composed by eco-sustainable and environmentally responsible components with hydrogen bonding (HB) donor and acceptor capabilities that enable the establishment of an extended HB network. The latter eventually leads to a substantial drop in the mixture melting point with respect to the one of the ideal mixture. Water-based NADES represent an exciting system that responds to the above mentioned criteria and contain water as a major component, rather than as an impurity or a deliberately added minor ingredient. Choline Chloride (ChCl, a well known HB acceptor in DES systems) forms NADES when mixed with water, which plays the role of HB donor. Several applications have already been identified for this system, but chemical physical properties of choline-rich mixtures, including the DES concentration, are not well established, yet. In order to overcame this limitation and introduce a subsequent, more systematic investigation of atomistic organization in these mixtures, here we report results from a series of chemical physical characterizations of water:ChCl with ratio ranging from 2 to 10 between ca. 280 and 330 K. Calorimetric measurements, density, viscosity, electric conductivity, refractive index, X-ray diffraction patterns and several 1H and 35Cl NMR spectroscopy observables are reported and compared with literature (when available). The deep eutectic nature of the water: ChCl 4:1 mixture is assessed, leading to the individuation of aquoline, as the corresponding DES. The other chemical physical properties are observed to vary, upon water content, in a monotone way, without abrupt changes across the eutectic concentration, thus providing support for the exploitation of the ChCl/water class of solvents, with tunable chemical-physical properties across their wide liquid range.

A Comprehensive Formulation of Aqueous Electrolytes for Low-Temperature Supercapacitors.

Safer-by-design and sustainable energy storage devices are envisioned to be among the required 2.0 solutions to satisfy the fast growing energy demands. Responding to this evolution cannot be freed from a global and synergetic approach to design the requisite electrolytes taking into account the toxicity, the eco-compatibility and the cost of their constituents. To target low-temperature applications, a non-toxic and cost-efficient eutectic system comprising LiNO3 in water with 1,3-propylene glycol as co-solvent was selected to design a ternary electrolyte with a wide liquid range. By using this electrolyte in an electrochemical double-layer capacitor (EDLC), the operating voltage of the device reaches an optimum of 2.0 V at -40 °C over more than 100 h of floating. Moreover, after being set up at 20 °C, the temperature resilience of the capacitance is near total, demonstrating thus a promising feature related to the suitable thermal and electrochemical behaviours of the tested EDLC devices.

Odyssey of Deep Eutectic Solvents as Sustainable Media for Multicomponent Reactions: An Update

Abstract:Deep eutectic solvents (DESs) are frequently defined as binary or ternary mixtures of compounds that are able to associate mainly via hydrogen bonds. As the interest in green sustainable solvent’s spread over the entire scientific community, DESs find applications as alternative solvents and/or catalysts for organic transformations. Advantages such as easy reproducible preparation, low cost, environmentally benign nature, wide liquid range, excellent thermal stability, negligible vapour pressure, recyclability, and tunable properties render DESs as a sustainable candidate of catalyst/solvent for futuristic transformations involving multicomponent strategy. In view of the escalating demand for green synthetic approaches, this paper retrospects the advances made in the application of DES in multicomponent reactions since 2018.

Textile handicraft for equipment-free fabrication of wearable low-cost diagnostic sensors for body-fluid based pathology

We report a low-cost, rapid and single-step method for fabricating microfluidic cloth-based analytical devices (μCADs) without involving any sophisticated instruments, simply by painting hydrophobic zones on cotton cloth using a liquid mixture primarily composed of polyurethane-based commercial wood finish. The mixture needs to be applied on cloth using a paint brush and subsequently dried in open air for only around 5 min to complete the process of hydrophobic barrier deposition. The painted regions show extreme hydrophobicity and demonstrate excellent barrier integrity and chemical inertness with a wide range of liquids, reagents, solvents and biological fluids. Channels of different designs are fabricated with sufficient dimensional reproducibility, despite adhering to manual painting step. Using this simple fabrication method, a colorimetric glucose detection assay is demonstrated on cloth-based devices, which has been found to be highly accurate as benchmarked with a laboratory-referenced biochemistry analyzer. The inherent simplicity and cost-effectiveness of this method is likely to foster sustainable growth of rural handicrafts specialized in manufacturing low-cost wearable sensors for rapid point-of-care diagnostics.

Hydrophobic Deep eutectic Solvents based on cineole and organic acids

The hydrophobic Natural Deep Eutectic Solvent formed by the combination of cineole and decanoic acid (capric acid) was studied using a combined experimental and computational approach. Experimental study was carried considering relevant physicochemical properties as density, viscosity, refraction index and thermal conductivity as a function of temperature, as well as Raman spectra for 785 nm excitation wavelength. Thermophysical properties measured showed a low -viscous low-dense fluid, which is of great relevance for its technological application, as well as the Raman spectra confirmed the formation of hydrogen bonding. The analysis of nanoscopic properties and structuring was carried out using theoretical method as the Density Functional Theory (BP86/def2-TZVP plus Grimme’s D3 theoretical level) and classical Molecular Dynamics simulation (using AMOEBA polarizable force field). Molecular modelling studies using quantum chemistry and classical molecular dynamics methods allowed a nanoscopic characterization of the fluid as well as of its intermolecular forces (hydrogen bonding). Phase equilibria were predicted using COSMO method considered solid–liquid (melting behavior) and vapor – liquid (evaporation), as well as excess properties. The COSMO results showed a low volatile, wide liquid range fluid, characterized by non-ideality because of the formation of hydrogen bonding. Likewise, the interaction of the considered material with POPC lipid was studied using COSMOperm method to analyze its behavior at lipid bilayers as models of cell membranes for the consideration of its possible toxicological effects, showing how the considered molecules are able to penetrate and disrupt the model membranes because of the lipophilic nature of the considered molecules.

Hydrodynamic forces in a horizontal-horizontal elbow in a gas-liquid system

Understanding the force fluctuations in an elbow is critical for piping system design, especially in multiphase flow applications. A new experimental facility has been designed and built where flow parameters, structural forces, and pressure upstream and downstream of the elbow can be measured simultaneously. The new facility allowed the study of the impact of different flow patterns on the phenomenon, with a wide range of liquid and gas superficial velocities (vSL 0.1-2.5 m/s, vSG 1-10 m/s). Oil and air have been used to represent field conditions better. In-situ liquid holdup and structure or translational velocity instead of mixture velocity are characterized. The flow influence as the peak force magnitude was measured on a single elbow (90-degree) oriented in a horizontal-horizontal configuration to identify the flow parameters with the most effect on the force. The results show that the density and velocity of coherent flow structures are essential to describe the force fluctuation. Additionally, pressure fluctuations in the elbow are significant for estimating the force in specific flow patterns.

Hydrogen bonding boosted oxidative desulfurization by ZnCl2/boric acid/polyethylene glycol-based ternary deep eutectic solvents

Deep eutectic solvents, as the novel and green solvents, are widely applied in various fields because of its unique and excellent quality, such as simple synthesis, non-toxic, biodegradable, wide range of liquids and strong solvation ability. In this work, a series of ternary deep eutectic solvents were synthesized using ZnCl2, boric acid (BA) and polyethylene glycol (PEG) with appropriate molar ratios by hydrogen bonds. Compared with binary DESs, ZnCl2/2BA/2PEG showed a better desulfurization performance, and 98.7 % sulfur removal was achieved. The hydrogen bonding interaction is considered as the key factor to the formation of DES and to promote the desulfurization reaction. In addition, BA and ZnCl2 play a synergistic and positive role in the desulfurization system. The DES was immiscible with fuel and could be reused for six cycles without a significant reduction in activity. The possible mechanism of the positive effect of hydrogen bonding interaction and O2•− free radicals was proposed. This work offers more possibility for designing new types of DESs for deep desulfurization of fuel oils and other applications in relation to extraction or catalysis.

In-situ polymerized separator enables propylene carbonate electrolyte compatible with high-performance lithium batteries

Propylene carbonate (PC) is a solvent of liquid electrolytes for lithium-based batteries. It has attracted considerable research attention, due to its high dielectric constant, high solubility for lithium salts, and wide liquid range. Lithium metal (Li) anodes do not have a graphitic intercalation structure, which prevents PC from forming a stable protective solid electrolyte interphase (SEI) and leads to catastrophic exfoliation; therefore, Li anodes are expected to use PC as the only solvent. However, batteries with the Li anodes are limited by low operating lifespans, because of the lithium dendrite and parasitic reaction between the electrolyte and Li electrode. Here, we report that by utilizing a uniform in-situ polymerized nanoporous separator, the lithium dendrite can be significantly suppressed. A Li-symmetric cell offers steady cycling for 1400 h. Moreover, a full LiCoO2│Li battery shows a good cycling performance even in a LiPF6/PC electrolyte both at room temperature and 60 °C. This work highlights the potential for the large-scale application of PC electrolytes in lithium batteries.

Dey-Biswas equation is highly effective for viscosity prediction of binary and multicomponent liquid mixtures including Ionic liquid mixtures

The recently developed Dey - Biswas has been put to test to demonstrate its consistency and efficacy on a wide range of organic liquid and Ionic liquid mixtures. It has also been tested over a broad range of temperatures to check its robustness since viscosity as a property is highly sensitive to temperature variations. This equation has been tested on 200 binaries, 30 ternaries, and 7 quaternary mixtures at varying temperatures. The results obtained have then been compared with eight well-established and some recently developed approaches. Furthermore, 2 recently developed approaches in 2021 and 2022 have also been included in the comparative study. The findings have been discussed by comparing the Average Absolute Percentage Deviations (AAPD) from the experimental values as a benchmark of predictive efficacy and consistency. The Grand AAPDs indicate that the Dey-Biswas approach is clearly superior being way ahead of its competing counterparts.It is seen to be performing extremely well even in the case of the IL mixtures.