Magnesium Perchlorate Research Articles

Flexible magnesium-ion-conducting solid poly-blend electrolyte films for magnesium-ion batteries

Solid biodegradable polymer electrolyte systems are considered the optimal choice for energy storage devices because they are both cost-effective and energy-efficient. A solid blend polymer electrolyte (SBPE) membrane capable of transporting magnesium ions was prepared using a mixture of 70 wt% methylcellulose, 30 wt% chitosan, and varying wt% magnesium perchlorate salt. X-ray diffraction analysis revealed an increase in the amorphous nature caused by the inclusion of Mg(ClO4)2 salt in the polymer blend matrix. A Fourier transform infrared spectroscopy study of samples containing varying salt concentrations revealed secondary interactions between polymer segments and salt, which provides the basis for energy density. Moreover, through impedance analysis, it was determined that the bulk resistance decreased with increasing salt concentration. The SBPE containing 30 wt% magnesium perchlorate exhibited the highest ionic conductivity, with a value of 2.49 × 10–6 S cm−1. A comprehensive evaluation of the ion transport parameters, including mobility, carrier density, and diffusion, was conducted for the prepared electrolyte samples. Notably, an ionic transference number (tion) of approximately 0.83 was observed for the SBPE sample with 30 wt% magnesium salt, indicating ions’ prevalence as the system’s primary charge carriers. Electrochemical analyses demonstrated that the SBPE with the highest ion conductivity possessed an electrochemical stability window (ESW) of 1.92 V. Additionally, the thermal characteristics of the samples were evaluated using thermogravimetric analysis (TGA) to assess the thermal stability of the electrolyte. Finally, the highest conducting polymer electrolyte was employed to construct a primary magnesium battery, and its discharge profile with different cathode materials was studied. Based on these findings, the current study suggests an environmentally friendly, biodegradable, and economically viable electrolyte option suitable for separator cum electrolytes in magnesium-ion batteries.

Development of Eco‐Friendly Chitosan‐Dextran Polyblend Electrolyte for Enhanced Performance in Primary Magnesium Batteries

The potential of next‐generation batteries lies in solid biodegradable polymer electrolytes. This research delves into a solid blend polymer electrolyte (SBPE) for magnesium conduction, utilizing a chitosan‐dextran blend matrix doped with magnesium perchlorate (Mg(ClO4)2) salt. The electrolyte films are prepared using a conventional solution casting technique. Through techniques like X‐ray diffraction and Fourier transform infrared spectroscopy, the successful incorporation of Mg(ClO4)2 into the blend matrix is confirmed. Notably, the SBPE containing 30 wt% of Mg(ClO4)2 demonstrates the highest ionic conductivity of 6.99 × 10−4 S cm−1 and a prominent ionic transference number of 0.84. Thermogravimetric analysis is carried out to study thermal stability. Differential scanning calorimetry analysis of the electrolyte systems gives insight into their thermal properties. Additionally, it showcases favorable electrochemical stability of 2.66 V. The oxidation and reduction peaks are observed in the cyclic voltammetry curve of the highest conducting sample. Furthermore, the discharge performance of Mg/(CS + DN + Mg(ClO4)2)/cathode cells is explored with varied cathode materials, illustrating the SBPE's potential for magnesium‐ion batteries. This study unveils a sustainable, biodegradable, and economical electrolyte solution for advanced energy storage systems.

The influence of oxychlorine phases on the flash pyrolysis of polycyclic aromatic hydrocarbons and implications for mars

A variety of chlorine-bearing hydrocarbons have been detected in the chemical analyses of soil and rock samples performed on Mars with the GCMS instruments onboard the Viking landers and the SAM instrument suite onboard the Curiosity rover. These aromatic and aliphatic chlorohydrocarbons are most likely produced by chemical reactions between salts (e.g., perchlorates, chlorates) and organic molecules of martian origin either during the thermal processing of the samples in flight or generated through radiation processes happening in Mars’ near surface. To understand the influence of salts on the organic molecules during pyrolysis and identify the potential precursors of the chlorohydrocarbons detected on Mars, we performed a systematic study and pyrolyzed three polycyclic aromatic hydrocarbons (PAHs)—naphthalene, phenanthrene, and benzanthracene—in the presence of six perchlorate and chlorate salts that have been identified or are most likely present on Mars—calcium perchlorate, iron perchlorate, sodium perchlorate, magnesium perchlorate, sodium chlorate, and potassium chlorate. Iron perchlorate had the strongest (oxy)chlorination power on the PAHs of all the salts tested whereas magnesium perchlorate and potassium chlorate were the most destructive ones. Despite the presence of these caustic salts, PAHs were highly chemically and thermally stable, suggesting they would likely be detectable natively if present in a martian sample. In addition, chlorohydrocarbons that are characteristic of the parent PAH were formed and could be used to help identify the nature of a PAH. This investigation underlines that PAHs could be the precursors of aromatic chlorohydrocarbons detected on Mars, but a definitive identification will require the detection of the parent PAHs and their respective pyrolyzates, molecules that were not yet detected on Mars likely because of the flight operating constraints of the SAM instrument.

Magnesium-eutectic electrolyte as a winning combination for sustainable battery

Eutectic-Magnesium electrolytes are sparsely used electrolytes in Magnesium ion batteries. In this context, readily available less toxic precursors based eutectic electrolytes are attracting increasing interest owing to the focus of sustainable battery development. The unique benefits of magnesium such as high specific capacity, low reduction potential, and remarkable reversibility without dendrimer formation are highly advantages when compare to lithium based batteries. Developing an optimal electrolyte composition is a key area of study in the field of battery technology. With improved cell performance, stability across cycles, and general safety, we hope to reduce unwanted interfacial reactions. In this study, we examined eutectic combination of trimethylamine hydrochloride and aluminium chloride (TMA: AlCl3 = TMA) along with magnesium perchlorate to understand ion-solvation, complexation, thermal stability, ion transport and conduction, and electrochemical stability, certain physico-chemical and electrochemical parameters were evaluated prior to assessing the cell's performance. The salient features being an ionic conductivity (σ) of 6.25×10−3 mS cm−1 at 30 °C, remarkable performance retention with over 90 cycles of operation with the electrolyte and an impressive capacity of 90 mAh/g. The behaviour of ionic conductivity with temperature followed the Vogel-Tammann-Fulcher (VTF) equation. Moreover, the anodic stability around 2.5 V (Mg/Mg2+) when platinum is used as the working electrode endorses the suitability of the electrolyte for use in Rechargeable Magnesium Batteries (RMBs).The promising results of this first investigation open up new possibilities for investigating complementary pairings with the aim of improving the efficiency of magnesium-ion cells.

Preservation of Bacillus subtilis' cellular liquid state at deep sub-zero temperatures in perchlorate brines.

Although a low temperature limit for life has not been established, it is thought that there exists a physical limit imposed by the onset of intracellular vitrification, typically occurring at ~-20 °C for unicellular organisms. Here, we show, through differential scanning calorimetry, that molar concentrations of magnesium perchlorate can depress the intracellular vitrification point of Bacillus subtilis cells to temperatures much lower than those previously reported. At 2.5 M Mg(ClO4)2, the peak vitrification temperature was lowered to -83 °C. Our results show that inorganic eutectic salts can in principle maintain liquid water in cells at much lower temperatures than those previously claimed as a lower limit to life, raising the prospects of active biochemical processes in low temperature natural settings. Our results may have implications for the habitability of Mars, where perchlorate salts are pervasive and potentially other terrestrial and extraterrestrial, cryosphere environments.

Long-Term Survivability of Tardigrade Paramacrobiotus experimentalis (Eutardigrada) at Increased Magnesium Perchlorate Levels: Implications for Astrobiological Research.

Perchlorate salts, including magnesium perchlorate, are highly toxic compounds that occur on Mars at levels far surpassing those on Earth and pose a significant challenge to the survival of life on this planet. Tardigrades are commonly known for their extraordinary resistance to extreme environmental conditions and are considered model organisms for space and astrobiological research. However, their long-term tolerance to perchlorate salts has not been the subject of any previous studies. Therefore, the present study aimed to assess whether the tardigrade species Paramacrobiotus experimentalis can survive and grow in an environment contaminated with high levels of magnesium perchlorates (0.25-1.0%, 1.5-6.0 mM ClO4- ions). The survival rate of tardigrades decreased with an increase in the concentration of the perchlorate solutions and varied from 83.3% (0.10% concentration) to 20.8% (0.25% concentration) over the course of 56 days of exposure. Tardigrades exposed to 0.15-0.25% magnesium perchlorate revealed significantly decreased body length. Our study indicates that tardigrades can survive and grow in relatively high concentrations of magnesium perchlorates, largely exceeding perchlorate levels observed naturally on Earth, indicating their potential use in Martian experiments.

Novel Solid Propellants Enabled Through In Situ Martian Perchlorates

With evidence for the native perchlorates existing in the Martian regolith, this paper examines the feasibility and performance of propellants formed from perchlorate salts reported to be present on Mars. Thermochemistry calculations indicate that the Martian perchlorate-based propellants provide less theoretical specific impulse than AP composite propellants but could still be viable propellants. Three propellants made from Martian perchlorates were manufactured and compared to a control propellant with AP as the oxidizer. Deflagration experiments were performed to obtain the burning rates as a function of pressure, with results comparable to AP baseline propellant. The propellant energy density was evaluated through bomb calorimetry. The propellant formulation with a similar perchlorate mixture to the distribution found in Martian soil was then subjected to thermal analysis, elemental analysis, and sensitivity testing to examine its combustion behavior and suitability for handling. Further characterization and development work would be needed to field these propellants, but initial conclusions indicate an in situ blend of calcium perchlorate and magnesium perchlorate could serve as a novel oxidizer for future safe, high-performing, and economical solid propellant rocket motors, offering an alternative to most current proposals for Martian ascent vehicle architectures.

Amorphous Magnesium-Doped Chitosan films as solid polymer electrolytes for energy storage device applications

Magnesium ion-conducting biodegradable solid polymer electrolyte (SPE) films of magnesium perchlorate [Mg(ClO4)2] doped Chitosan [CS] were prepared using the solution casting technique at room temperature. XRD study shows that amorphous nature of the polymer matrix increases upon doping. FTIR deconvolution confirm the complexation generated between the salt and the polymer. The current–voltage measurement exhibited electrochemical stability window for all samples above 2.14 V. The ionic transference number for the highest conducting sample was 0.99. The impedance analysis was done for each SPE film, and the sample with the highest concentration (40 wt%) exhibited the highest conductivity, 5.7 × 10-4 Scm−1. The prepared primary magnesium battery using the highest conducting SPE showed open circuit potential of 2.112 V. Due to its exceptional qualities, this prepared electrolyte may be a strong contender for energy storage systems.

Bacterial model membranes under the harsh subsurface conditions of Mars.

Biomembranes are a key component of all living systems. Most research on membranes is restricted to ambient physiological conditions. However, the influence of extreme conditions, such as the deep subsurface on Earth or extraterrestrial environments, is less well understood. The deep subsurface of Mars is thought to harbour high concentrations of chaotropic salts in brines, yet we know little about how these conditions would influence the habitability of such environments. Here, we investigated the combined effects of high concentrations of Mars-relevant salts, including sodium and magnesium perchlorate and sulphate, and high hydrostatic pressure on the stability, structure, and function of a bacterial model membrane. To this end, several biophysical techniques have been employed, including calorimetry, fluorescence and CD spectroscopy, confocal microscopy, and small-angle X-ray scattering. We demonstrate that sulphate and perchlorate salts affect the properties of the membrane differently, depending on the counterion present (Na+vs. Mg2+). We found that the perchlorates, which are believed to be abundant salts in the Martian environment, induce a more hydrated and less ordered membrane, strongly favouring the physiologically relevant fluid-like phase of the membrane even under high-pressure stress. Moreover, we show that the activity of the phospholipase A2 is strongly modulated by both high pressure and salt. Compellingly, in the presence of the chaotropic perchlorate, the enzymatic reaction proceeded at a reasonable rate even in the presence of condensing Mg2+ and at high pressure, suggesting that bacterial membranes could still persist when challenged to function in such a highly stressed Martian environment.

Thermodynamic modeling of calcium or magnesium chloride, chlorate, and perchlorate ternary mixtures deliquescence at Mars-relevant temperatures

The definition of habitability on Mars is intimately linked to the stability of liquid water on the surface or near sub-surface. Brines provide the best pathway to stabilize liquid water, and form through deliquescence where a solid salt crystal transitions into an aqueous solution when exposed to a humid atmosphere. In a typical brine controlled by temperature and water relative humidity, ternary mixtures represent the best potential liquid brines. Here we modeled the deliquescence relative humidity (DRH) and the eutonic relative humidity (RH) of ternary salt mixtures. Chloride, chlorate, and perchlorate were modeled with either calcium or magnesium as the cation at temperatures ranging from 223 to 273 K. For the calcium ternary mixtures, the main salt composition precipitating at the DRH was dominated by calcium chloride, and by magnesium perchlorate in the magnesium ternary system. The hydration state of the precipitating salts systematically increased as temperature decreased. The eutonic RH for the calcium mixtures ranged from 14.24% at 273 K and increased to 43.54% by the coldest temperature of 223 K. The eutonic RH for the magnesium mixtures was significantly higher than the calcium counterpart, at 49.76% at 273 K and increased to 53.09% by 223 K. Calcium perchlorate was the predominate eutonic precipitate for the calcium mixtures, and magnesium chlorate for the magnesium mixtures., This study shows that ternary mixtures bring a slight improvement to the stability of brines on Mars compared to single salts or binary mixtures.

Regolith Inhibits Salt and Ice Crystallization in Mg(ClO4)2 Brine, Implying More Persistent and Potentially Habitable Brines on Mars

On Mars, liquid water may form in regolith when perchlorate salts absorb water vapor and dissolve into brine, or when ice-salt mixtures reach their melting temperature and thaw. Brines created in this way can chemically react with minerals, alter the mechanical properties of regolith, mobilize salts in the soil, and potentially create habitable environments. Although Martian brines would exist in contact with regolith, few studies have investigated how regolith alters the formation and stability of brines at Mars-relevant conditions. To fill this gap, we studied magnesium perchlorate brine in a Martian regolith simulant at salt concentrations up to 5.8 wt.%. We measured the water mass fraction and water activity between 3 and 98% relative humidity at 25 °C using the isopiestic method, and monitored salt and ice crystallization between −150 °C and 20 °C with differential scanning calorimetry. Results show that regolith inhibits salt and ice crystallization, allowing water to form and persist at much colder and drier conditions than pure brine. Remarkably, in several samples, neither salt nor ice crystallized at any conditions. These results suggest that brines could exist in regolith for longer periods of the Martian year than previously thought, and could persist indefinitely under certain conditions. By retaining water, inhibiting salt and ice crystallization, and maintaining habitable water activity, briny regolith may be a more favorable environment for life than pure brine alone. These findings indicate the critical importance of brine–regolith interactions for understanding the properties, evolution, and potential habitability of Mars’s surface.

Tolerance against exposure to solution of magnesium perchlorate in microinvertebrates

Abstract Perchlorates are present at high concentrations in Martian regolith and pose an additional challenge to the survival of terrestrial life on Mars. Some microinvertebrates can resist extreme conditions (e.g. low temperatures, lack of oxygen and radiation), making them suitable model species for space experiments. Clarification of whether they can tolerate high levels of perchlorates is crucial for understanding the scope of application of small invertebrates in Mars exploration. We assessed the activity of some Crustacea, Nematoda, Rotifera and Tardigrada exposed to 0.25–1.00% magnesium perchlorate. The number of active specimens decreased with exposure time and perchlorate concentration. However, exposure of selected species to 0.25% perchlorate for 24 or 72 h showed activity in some specimens. Only Caenorhabditis elegans, Lecane inermis and Artemia salina exhibited activity after 24 h exposure to 1.00% perchlorate. Lecane inermis was the only species to remain active after 72 h of incubation with 1.00% perchlorate. Transferring specimens to distilled water after perchlorate exposure generally resulted in high recovery rates. The study indicates that all the tested invertebrates resist extremely high concentrations of perchlorates, which has implications for further research on their potential use in development of biological systems with improved performance and utility on Mars.

Sodium Alginate Doped with Magnesium Perchlorate as Solid Biopolymer Electrolytes for Energy Storage Applications

AbstractThis paper deals with development and characterization of the solid biopolymer electrolyte using Sodium alginate as the host biopolymer and magnesium perchlorate used as a doping salt. Membranes are prepared via solution casting technique. Several characterization techniques, such as X‐ray and diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry, AC impedance spectroscopy, linear sweep voltammetry, and transference number measurement are performed to characterize the prepared biopolymer membrane. The highest ionic conductivity 2.41 × 10−3 S cm−1 is observed for prepared solid biopolymer electrolyte contains 40:60 m wt% of NaAlg:Mg(ClO4)2. The electrochemical stability of highest ion conducting biopolymer membrane is observed at 3.62 V. A primary magnesium battery is constructed using the highest ionic conducting biopolymer membrane and the open circuit voltage of the fabricated magnesium battery is found to be 2.0 V.

Antimicrobial and Molecular Docking Studies of Novel Synthesized α‐Aminophosphonates Based on Pyrozol Moiety as Anticancer Agents via α‐Topoisomerase II Inhibition

AbstractThe reaction of (1,3‐diphenyl‐1H‐pyrazole‐4‐carbaldehyde) with different aromatic amines and triethylphosphite in the presence of magnesium perchlorate as a catalyst resulted in high yields of new α‐aminophosphonates containing pyrazole moiety. The structures of the newly prepared α‐aminophosphonates were confirmed using IR, elemental analysis, 1H NMR, and 13C NMR spectra. The antibacterial analysis of the prepared compounds showed potential inhibitory effects against the selected bacterial strains with minimal inhibitory concentrations (MIC) ranging from 12.5 to 3.125 mg/mL compared to the start compound. Some compounds have exhibited higher DPPH scavenging activity. Further, the molecular docking studies illustrated that the synthesized compounds have an inhibitory effect against topoisomerase II, which targets many approved drugs. The best modified α‐aminophosphonates compound had the highest binding affinity, with a value of −7.57 kcal/mol. Modified α‐aminophosphonates can be employed as a feasible starting point for generating new antimicrobial and anticancer agents and incorporating new reducing agents into therapeutic formulations.

Changes in membrane fatty acids of a halo-psychrophile exposed to magnesium perchlorate and low temperatures: Implications for Mars habitability

The presence of perchlorate salts in aqueous solutions bears two opposite effects on habitability. On the one hand, perchlorate salts trigger a decrease in the freezing point of the aqueous solutions, resulting in stable aqueous solutions at subzero temperatures, thereby widening the habitable conditions for potential microbial life. On the other hand, the presence of perchlorates in solution imposes a significant osmotic stress that compromises the integrity of microbial cell membranes, thereby restricting the habitable conditions in the same aqueous environment. Here we investigated the survivability and the changes in the composition of membrane fatty acids (FAs) of the bacterium Rhodococcus sp. JG-3 cells under warm (20°C), cold (4°C), and subzero temperatures (−10°C and −16°C), and in the presence (8 wt% and 16 wt%) and absence of magnesium perchlorate (Mg(ClO4)2). Bacterial cell survivability decreased with decreasing temperature and presence of magnesium perchlorate. However, Rhodococcus sp. JG-3 was able to tolerate up to 8 wt% Mg(ClO4)2 at −16°C. The presence of magnesium perchlorate in the medium decreased the concentration of total FAs, likely due to a destabilization of the molecules by the chaotropic effect of the perchlorate anion. At the maximum stress (both subzero temperatures and 16 wt% magnesium perchlorate), the composition of FAs changed, i.e., Rhodococcus sp. JG-3 cells increased the relative abundance of saturated FAs (SFAs) over the unsaturated (UFAs) or branched (BFAs). These changes in the proportion of FAs types may be a physiological response during cooling, aimed to improve lipid membrane stability. Interestingly, the composition and relative abundance of fatty acid types (i.e., SFAs, UFAs and BFAs) of Rhodococcus sp. JG-3 when simultaneously exposed to subzero temperatures and 16 wt% magnesium perchlorate was similar to that following freezing stress alone, suggesting that either both conditions triggered a similar response or that one response dominated over the other. Our findings contribute to understand the survivability and adaptation of extremophilic microorganisms under polyextreme conditions, such as those existing in the Martian subsurface today and/or in the past, which include the documented presence of magnesium perchlorate salts in ancient sediments and global cold temperatures.

Improved performance of biopolymer composite electrolyte based cellulose acetate/Zinc Oxide filler for supercapacitors

Biopolymer composite electrolytes consisting of cellulose acetate and magnesium perchlorate with different weight percent (wt.%) of Zinc Oxide fillers were prepared using the standard solution cast technique. The effect of incorporating various amounts of ZnO fillers in our composite electrolytes was investigated for their electrical and structural properties, and ion transference numbers. The ionic conductivity of 40 wt.% ZnO filler was found to be 8.75× 10−4 S/cm at 30 °C along with a 4.2 V electrochemical stability window. The ion transference number has been found to be 0.97 for CA + 40 wt.% of Mg(ClO4)2 + 40 wt.% with ZnO fillers. Furthermore, the electrochemical performances of the prepared electrolytes have also been investigated. The fabricated cell with this electrolyte shows an enhanced energy and high-power density of 2.78 Wh/Kg and 1000 W/Kg, respectively. An increase in the above-mentioned densities may be attributed to the high ionic conductivity ZnO fillers in the biopolymer matrix. Additionally, it shows 100% capacitance retention along with high coulombic efficiency after the 129th cycle.

Preparation of primary magnesium battery based on kappa carrageenan with magnesium perchlorate and its application to electrochemical devices

Preparation of primary magnesium battery based on kappa carrageenan with magnesium perchlorate and its application to electrochemical devices

A possible perchlorate-enabled mechanism for forming thick near surface excess ice layers; in the Amazonian regolith of Mars

We use the freezing point depressing magnesium and calcium perchlorates in Martian regolith to redistribute ground ice by residual liquid water migration following the initial emplacement of ground ice by vapour deposition. This residual liquid water is moved by forces generated by periodic surface temperatures that decay with depth in conjunction with the geothermal vertical temperature gradient. We examine the period means of the bulk water speeds with depth and the mean divergence of the bulk water speeds, which relates to the rate of change in ice content in the regolith. Silt and clay rich regoliths behave differently. In silty regolith, for the short 1.88 a period and for longer 50 ka (precession) and 120 ka (obliquity) temperature cycles, there is a mean movement of liquid perchlorate aqueous solution that results in formation of near surface excess ice layers. The excess ice formed by the seasonal 1.88a period is confined at high latitudes to the upper meter of regolith. For the longer periods, there is a well-defined surface temperature region where near surface thick (≥40 m) excess ice layers form; (from 192 K to 210 K). For mean surface temperatures <192 K no near surface thick excess ice layers formed, but deeper layers are predicted and followed. The formation of excess ice layers in silt near the surface is controlled by the relationship between the temperature cycles, geothermal gradient and the eutectic temperature of the perchlorate (eg. ~198 K for Ca and ~ 205 K for Mg perchlorate). At a given depth if the periodic temperature is below the eutectic then there is nearly no liquid water left and what there is has much higher viscosity. The sudden change in the liquid water amount and viscosity with temperature generates net average water speeds in silts that are two orders larger than in clays.

Preparation and characterization of biopolymer electrolyte based on gellan gum with magnesium perchlorate for magnesium battery

Preparation and characterization of biopolymer electrolyte based on gellan gum with magnesium perchlorate for magnesium battery

Structural Responses of Nucleic Acids to Mars-Relevant Salts at Deep Subsurface Conditions.

High pressure deep subsurface environments of Mars may harbor high concentrations of dissolved salts, such as perchlorates, yet we know little about how these salts influence the conditions for life, particularly in combination with high hydrostatic pressure. We investigated the effects of high magnesium perchlorate concentrations compared to sodium and magnesium chloride salts and high pressure on the conformational dynamics and stability of double-stranded B-DNA and, as a representative of a non-canonical DNA structure, a DNA-hairpin (HP), whose structure is known to be rather pressure-sensitive. To this end, fluorescence spectroscopies including single-molecule FRET methodology were applied. Our results show that the stability both of the B-DNA as well as the DNA-HP is largely preserved at high pressures and high salt concentrations, including the presence of chaotropic perchlorates. The perchlorate anion has a small destabilizing effect compared to chloride, however. These results show that high pressures at the kbar level and perchlorate anions can modify the stability of nucleic acids, but that they do not represent a barrier to the gross stability of such molecules in conditions associated with the deep subsurface of Mars.