Thermal Transformation Research Articles

Application of Sublimation in the Synthesis and Crystal Growth of Organosulfones.

The solvent-free elimination of sulfinic acid and aromatization of 1,6-trans-substituted bis(arylsulfone) trienes is reported. It is shown that sublimation can be used as a 'green' method to combine the thermal transformation of six trienes and the crystal growth of the resulting 4-(phenylsulfonyl)biphenyls. When the sublimation conditions are carefully controlled, high quality single crystals of the 4-(phenylsulfonyl)biphenyls are obtained. Theoretical modelling of the reaction using the simplified triene Ph-(CH)6-SO2H showed that the cyclization is energetically feasible and that the complete conversion is possible during the timescale of the sublimation. At temperatures slightly higher than the optimum sublimation temperature two of the trienes transformed into 1,4-cyclohexadienes that did not eliminate phenylsulfinic acid. A reaction mechanism involving a 1,3-hydrogen shift induced by free PhS. radicals is proposed for the formation of the 1,4-cyclohexadienes.

Optimizing ageing conditions for commercial NiTi archwires: Insights from thermal phase transformation and tensile deformation analysis

Superelastic nickel-titanium (NiTi) archwires are now commonly used as the standard archwire during the orthodontic alignment and levelling stage. They are preferred due to their ability to apply minimal force on teeth while allowing for a wide range of tooth movements. During orthodontic treatment, the orthodontist assesses the dimension and shape of the NiTi archwire to determine the amount and direction of force required to align misaligned teeth. The main contribution of this study is the parametric analysis and establishment of a set of optimal ageing temperatures and duration for the investigation of functionally graded nickel-titanium archwire using differential scanning calorimetry (DSC) and tensile deformation testing. The mechanical and thermal phase transformation behavior after ageing at six temperatures for duration of 15 minutes have been investigated using tensile deformation test and differential scanning calorimetry (DSC) test in this paper. Experimental results reveal that in thermal analysis as the ageing temperatures increase from 400 °C to 490 °C, the austenite finish temperature rises to a value between 9.53 °C and 35.48 °C, and subsequently decreases to 520 °C. The archwire specimen aged for temperature of 490 °C exhibited the austenite finish temperature of around 35.48 °C, and it is highest among the aged wire specimens closest to oral temperature. In tensile deformation, the ideal ageing temperature for orthodontic applications was determined to be 490 °C for 15 minutes, resulting in relatively low plateau slope 13.73 GPa with high superelatic ratio 12.04, and maximum plateau strain of 7 %.

Ensuing the formation of photocatalytic TiO2/Fe2O3 nanocomposite from heat treatment of electrophoretically deposited TiO2 films on stainless steel

In this study, thermal transformations in electrophoreticlly coated TiO2 coatings on SS-316L substrate were investigated. Such films were previously employed for antibcaterial purposes, however their heat-treatment at 900 °C resulted in an unexpected transformation in the film color. This study was designed to trace back the origin of such optical transformation in the TiO2 film that was expected to be whitish in its outlook, however it became brownish at elevated temperature, indicating an exploitable characteristics of visible light absorbance. The films were carefully transformed to particles by subsequently applying scratching/ball milling method and characterized through various materials’ characterization tools including but not limited to SEM-(EDS), XRD, alongside characteristic characterizations such as TGA, UV-Vis and EIS for elucidating thermal, optical and electrochemical behavior respectively of particles obtained from pristine (TiO2) and heat-treated films (termed as TFNC) owing to the transformation of TiO2 to TNFC (i.e. TiO2/Fe2O3) nanocomposite. TFNC exhibited decreased band gap from 3.2 eV to 2.86 eV and consequently improved photocatalytic activity. The TFNC degraded 50% Rhodamine B dye under visible light, while pure TiO2 degraded only 13%, which was credited to the formation of Fe2O3 particles inside TiO2 film. It was estimated that the Fe-element was capable to diffuse inside such TiO2 film and resulted the formation of TFNC at ≥ 900°C. The evolution of visible light dependent photocatalytic performance in TFNC was credited to the lowering of bandgap and enhanced electron-hole generation as investigated by EIS.

Molecular Photothermal Conversion Catalyst Promotes Photocontrolled Atom Transfer Radical Polymerization.

Photothermal conversion is a growing research area that promotes thermal transformations with visible light irradiation. However, few examples of dual photothermal conversion and catalysis limit the power of this phenomenon. Here, we take inspiration from nature's ability to use porphyrinic compounds for nonradiative relaxation to convert light into heat to facilitate thermal polymerization catalysis. We identify the photothermal conversion catalytic activity of a vitamin B12 derivative, heptamethyl ester cobyrinate (HME-Cob), to perform atom transfer radical polymerization (ATRP) under irradiation. Rapid polymerization are obtained under photothermal activation while maintaining good control over polymerization with the aid of a photoinitiator to enable light-induced catalyst regeneration. The catalyst exhibits exquisite temporal control in photocontrolled thermal polymerization. Ultimately, the activation of this complex is accessed across a broad range of wavelengths, including near-IR light, with excellent temporal control. This work showcases the potential of developing photothermal conversion catalysts.

Nitrogen isotopes of released gas from rock crushing and implications to origins of molecular nitrogen in Lower Cambrian overmature shale gas in South China

The origin and formation mechanism of N2-rich Lower Cambrian shale gas remain ambiguous, posing serious exploration risks in the Lower Cambrian shale gas in South China. In this study, high-vacuum-pulsed electromagnetic and helium-filled ball-mill rock-crushing methods were developed to measure the released gas contents, compositions and nitrogen isotopes of N2 in shale-crushed gas from Lower Cambrian organic-rich shales in South China. Key factors in N2 enrichment in shale gas and its origins were investigated. Results showed that mineral compositions and thermal maturity affected the contents and compositions of shale-crushed gas. Carbonate cementation, and feldspar dissolution and reprecipitation, formed isolated pores filled with migrated bitumen and thus generated high gas contents with larger CH4/N2 ratios of shale-crushed gas. The thermal maturation of Lower Cambrian organic-rich shale can be further divided into the early and late stages of overmaturation with a boundary of 3.4–3.5%EqVRo. The contents and CH4/N2 ratios of shale-crushed gas continued to increase at the early stage of overmaturation, and then a rapid decrease at the late stage of overmaturation (>3.4–3.5%EqVRo), reflecting the release of large amounts of N2 by intensified aromatization of organic matter. An empirical equation of TONb = 0.0138 × TOC with R2>0.98 was used to estimate the relative contribution of inorganic nitrogen (TINb) and organic nitrogen (TONb) to the bulk of nitrogen content in the overmature Cambrian shale. The EqVRo-δ15NN2 plot allows identification of N2 derived from thermal decomposition of ammonium-bearing clay minerals or residual kerogen. The N2 generated at the early stage of overmaturation (including at wells LX03, EYY1, SNY1 and W001-4) in Lower Cambrian shale gas is characterized by δ15NN2 values ranging from −2 to +2‰, mainly reflecting thermal deammoniation and decomposition of ammonium-bearing clay minerals. In contrast, the N2 generated at the late stage of overmaturation (DQ outcrop) in Lower Cambrian shale gas is characterized by δ15NN2 values greater than +4‰, indicating thermal cracking of pyridinic nitrogen and pyrrolic nitrogen. The N2 generated from thermal transformation of ammonium-bearing clay minerals and pyridinic nitrogen and pyrrolic nitrogen is the main source of N2-rich shale gas in the Lower Cambrian shale of South China.

Black TiO2-infused polydimethylsiloxane composites for efficient solar-assisted water evaporation and thermoelectric energy generation

Solar assisted interfacial water evaporation through the strategic localization of solar- thermal energy conversion by relying on the air–water interface has garnered significant interest owing to its enhanced efficiency in a variety of applications, from water purification to energy generation. Nevertheless, achieving utterly improved thermal management to enhance the efficiency of solar heat consumption is still quite complex. Herein, we created special composites of black titanium dioxide and polydimethylsiloxane (B-TiO2/PDMS) aiming effectively harvest a broad range of spectrum of solar radiation for the benefit of improving energy production and aid for water purification. The B-TiO2/PDMS sponge possesses an impressive optical to thermal transformation as an outcome, keeping a constant surface temperature of 66 °C, as opposed to 41.6 °C for PDMS sponge at typical 1 sun intensity for 10 min. This solar evaporation system constitutes a greater evaporation rate of 1.39 Kg m−2h−1 with a photothermal conversion efficiency of 70.8 % under 1 sun illumination. To accomplish integrated thermoelectric power generation during solar evaporation, the thermoelectric (TE) module is used as an insulating medium, succeeding an optimal yield of 30 mV under 1 sun. Furthermore, the as prepared B-TiO2/PDMS sponge achieved notable mechanical resilience and incredible adaptability, offering a viable approach for thermal management and cooperative way to utilize solar powered evaporation to produce potable water and energy.

A simple but effective method for the enrichment of Al in red mud waste

This study proposes transforming red mud, an abundant byproduct from the aluminum industry, into minerals using Na2CO3 activation for efficient water leaching. It was aimed at breaking down the rigid Al-Si network structure. The investigation compares the effects of sodium salts, with Na2CO3 achieving an 88.90 % aluminum leaching rate crucial for activating katoite and cancrinite in red mud. Using XRD, FT-IR, SEM-EDS, in situ hot-stage microscopy, FactSage, and Material Flow Analysis, the study explores changes in Na2CO3-loaded red mud, elucidating its role in converting aluminum-bearing minerals into water-soluble aluminates at a low temperature of 900 °C for an optimum activation duration of 90 min, with a preferred loading of 32 % Na2CO3. Introducing a new cyclic aluminum extraction method from red mud, utilizing sodium salts, especially Na2CO3, the study optimizes the activation process through a comprehensive exploration of thermal and mineral transformation behaviors. Quantitative analysis of Na and Al elements ensures successful recovery and cyclic utilization of Na2CO3, maintaining aluminum extraction efficiency above 82 % after six cycles. This economically feasible closed-loop system aligns with principles of industrial efficiency and climate change mitigation. Na2CO3, acting as an activator and a carbon sink, showcases significant potential for sustainable aluminum production.

Synthesis and phase transformation study of nanostructured manganese oxide polymorphs

This paper presents the green synthesis of manganese oxide nanoparticles using olive leaf extract (OLE). The extract functions as both a reducing agent, responsible for converting manganese ions into nanoparticles, and a capping agent, aiding in stabilizing the formed nanoparticles. Our focus lies on investigating the thermal stability, phase transformation, and decomposition temperatures of different manganese oxide phases in powder form as a function of the calcination temperature. Since phase transformation depends on temperatures change at the nanoscale both thermogravimetric and differential scanning calorimetry (TGA, DSC) are used to determine the new phase transformation temperatures of the synthesized nanoparticles. Moreover, the phase structure and the exact stoichiometry are studied using ex-situ X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning/transmission electron microscopy (SEM/TEM). XRD and XPS analyses reveal the formation of amorphous MnOx at room temperature (prior to calcination), transitioning to crystalline phases (Mn2O3 and Mn3O4) post-calcination. High-resolution TEM and SEM depict the formation of nanoparticles around 15 nm in size, exhibiting different shapes. BET technique calculations give a very high specific surface area, rending these nanoparticles excellent candidates for several applications.

High‐performance BCN‐C heterostructured electrocatalyst derived from covalent triazine frameworks for nitrogen reduction

AbstractDesigning and synthesizing heterostructure‐based catalysis combining two‐dimensional (2D) materials has attracted enormous attention in materials chemistry, especially for electrocatalysis, due to their tunable electronic properties and structure. In this work, a boron carbon nitride (BCN)‐coupled carbon (BCN‐C) heterostructure with improved electronic performance was synthesized starting from C‐ and N‐enriched 2D covalent triazine frameworks (CTFs) via a simple thermal transformation process using NaBH4 as the B source. The characterizations results showed that the B released from NaBH4 reacted with N and C in CTF, forming the BCN‐C heterostructure coupling the BCN and carbon with a strong interfacial effect. The electrocatalytic NRR experiments and density functional theory (DFT) calculation revealed that the interfacial electronic properties and large numbers of active sites of the BCN‐C heterostructure benefited the NRR. The BCN‐C‐1 catalyst showed a high Faradaic efficiency of 27.8% and an NH3 yield of 4.3 μg h−1 mgcat.−1 in 0.1 M HCl electrolyte, owing to its high specific surface area (288 m2/g) with a large number of exposed active sites and the Mott–Schottky effect from the BCN‐C heterostructure. This work highlights the design and synthesis of metal‐free catalysts with high activity and selectivity and makes them excellent candidates for electrocatalytic applications.

Thermal plasma spraying of NiTi powder for thick coating of shape memory alloy

In this article, NiTi coating was fabricated via a thermal plasma process by tuning various parameters. The work aims to achieve shape memory behavior that could retained in the plasma-sprayed samples. Various plasma spraying process parameters such as plasma power, powder feed rate, spraying plan, and net powder spray were taken into consideration for the spraying. Microstructural, thermal, mechanical, and shape memory behavior was analyzed on the plasma-sprayed samples. Various phases austenite, martensite, and intermetallic phases such as NixTiy, Ni-Ti-O, Ni, and Ti were confirmed from the X-ray diffraction analysis. The presence of these phases in the samples contributes to the thermal transformation and mechanical behavior. A less heat-affected zone of 10 µm along the interface was confirmed without any diffusion of elements from the substrate to the coating layers. There was a homogenous distribution elemental composition of Ni and Ti throughout the coating layers. The shape memory behavior of the coating samples was confirmed by the thermo-mechanical analysis by performing the response in multiple cycles.

Chemical characteristics via quantitative photoelectron analysis of chemical-solution-deposited yttrium oxide thin films for metal-insulator-metal capacitor applications

A cost-effective chemical bath deposition coupled with an annealing methodology is presented for obtaining yttrium oxide (Y2O3) thin films. The resultant thin films are homogeneous, free of pinholes, and show a relatively low surface roughness. The detailed characterization of the as-deposited thin film and the determination of optical, structural, and chemical characteristics of the films upon thermal transformation at 500 °C for 2 h was done with thermogravimetric analysis, X-ray diffraction, UV–Vis spectroscopy, surface topology analysis, and X-ray photoelectron spectroscopy. The results reveal that the as-deposited thin film is composed of an amorphous YOOH compound intrinsic to the synthesis process. However, with annealing, it is crystallized and transformed into a Y2O3 thin film showing a high optical transparency. The characteristics of the film are found to be influenced by the Y‒OH and Y‒O content with direct influence on the shape of the photoelectron spectra of the thin films showing a binding energy downshift of 1.6 eV from the 158.84 eV peak position found for the YOOH sample after annealing. The estimated surface roughness for the as-deposited YOOH and annealed Y2O3 samples resulted in 2.7 and 3.8 nm, respectively. The electrical characteristics and potential performance as a dielectric layer have been assessed in a Metal-Insulator-Metal configuration, where the acceptable values for leakage current in the 6 × 10−4 − 3 × 10−6 A/cm2 range and a capacitance of 218 and 80 nF/cm2 were measured for the YOOH and Y2O3 thin films, respectively. The latter indicates that these films are suitable candidates for gate dielectric transistor applications with the advantage of them being films produced via an economical and technically simple scalable process.

Synthesis of graphene oxide from post-consumer PET bottles by a one-step thermal treatment in air atmosphere for removal of methylene blue

Post-consumer polyethylene terephthalate (PET) bottles are promising raw materials to produce value-added materials. This work uses a simple thermal treatment (TT) in an air atmosphere to transform post-consumer PET (PET-W) into graphene-oxide-like material (GOL). A careful analysis of the thermogravimetric (TGA) curves allowed us to determine the optimal temperature for controlling the oxidative decomposition reactions of PET-W at 412 °C while maximizing the bidimensional character of the products. The products of thermal transformation were characterized by Raman spectroscopy, DRX, FTIR, SEM, EDS, XPS, and BET. The results of the characterization indicate the obtaining of a material (identified here as GOLPET) which is characterized by an ID/IG ratio of 0.61, the presence of oxygenated groups such as CO, C-O-C and phenyls at the interphase, and an elemental composition of ∼83.7 (wt.%) and ∼16.27% of carbon and oxygen (wt.%), respectively. XPS allowed us to determine the formation of assembled aromatic chains (Csp2 = 61.53%) and acyclic chains (Csp3=38.47%). Finally, GOLPET absorption capacity was explored for a commercial application such as removing methylene blue (MB dye); complete elimination of MB (99.6%) in an aqueous solution was demonstrated. Considering the annual generation of plastic waste ∼300 million t, the methodology developed in this research can be envisage as an affordable and innovative alternative to produce GO-like materials.

Self-densification behaviors and oxidation resistance properties of a slurry-derived ZrB2-SiC coating with kyanite additive

The great advantages of component designability, operation convenience, and cost reduction make the slurry-sintering method promising for preparing oxidation resistant coatings. However, the porous structure caused by the volatilization of liquid in the slurry and shrinkage of particles in the pressureless sintering limits its practical and wide application. Herein, a dense ZrB2-SiC coating with improved oxidation resistance was fabricated via a slurry-sintering method on C/SiC composites by introducing kyanite into the slurry. The self-densification of the coating is achieved due to the volume expansion of 26.1 % related to the irreversible thermal transformation from kyanite to mullite during sintering. The resultant dense coating with a thickness of 150 μm shows the good interfacial bonding strength of 19.2 MPa and the low weight changes of 1.7 %, −0.6 %, and −1.7 % at 800 °C, 1000 °C, and 1200 °C for 40-h oxidation, respectively.

Geoffrey Eglinton. 1 November 1927—11 March 2016

Where have all life's molecules gone? Recycled to carbon dioxide every one! Ah! But look—a hardy few remain As biomarkers imprisoned in the fossil domain (G. Eglinton & R. Pancost, Immortal molecules ( 47 )) Geoffrey Eglinton trained as an organic chemist at the University of Manchester working on acetylene synthesis, and the Eglinton reaction signifies his discovery of an effective method for their oxidative coupling. At the University of Glasgow, he recognized the potential of analytical advances to open new frontiers for characterization of molecular constituents of complex mixtures and continued to adopt and adapt instrumental techniques throughout his career. Eglinton's exploration of plant leaf waxes, and their taxonomic profiles, prompted forays in organic geochemistry, seeking molecular evidence for ancient life. Thus, his focus shifted to studying ‘chemical fossils’ preserved in the rock record and pioneering identification and interpretation of their compositions. At the University of Bristol, he established the Organic Geochemistry Unit and steered its rise to international prominence as a leading centre for research, a legacy that continues today. He served in planning the Apollo sampling programme and led research that explicated the carbon chemistry of the Moon. Major advances in using molecules as witnesses of the origins and fate of sedimentary organic matter bear the hallmarks of his insightful contributions and commitment to interdisciplinary, collaborative ventures. They include deciphering how environmental controls and thermal transformations govern the composition of petroleum hydrocarbons, and validating the ability for molecules to afford invaluable evidence of past climates. Eglinton's research accomplishments were recognized by many prestigious awards, including a Royal Gold Medal of the Royal Society, the V. M. Goldschmidt Medal of the Geochemical Society, the Wollaston Medal of the Geological Society, and the Dan David Prize.

Enhancing the Performance of a Hazardous Waste Incineration Facility through the Usage of a Dedicated Application

Thermal transformation of waste carried out in a rotary kiln is a complex process, usually involving hazardous waste. Due to the great diversity of these wastes and their specific properties, the process of their thermal transformation may be associated with various types of operational problems. The reasons for their occurrence include, among others, processes potentially affecting the deterioration of the condition of the rotary kiln lining. In order to minimize problems, a tool is proposed to support the work of incineration plant operators. This is an application that enables generation of input material portions in subsequent kiln feeds. It is characterized by wide functionality, including the ability to assign higher weights to selected parameters. The application is based on an algorithm that takes into account the key waste parameters from the point of view of the thermal process, which have been given specific value ranges. Two series of simulations were performed with the same assumptions except for change in the weight for one of the parameters in the second case. In the first series, the following ranges of the considered parameters were obtained: calorific value 14.96–20.66 MJ/kg, pH 5.59–8.11, content of alkaline salts 1.42–7.39, content of chlorine 1.1–3.83, content of halogens 0.08–0.97. In the second series of simulations, the favored parameter was the calorific value, which ranged from 17.08 MJ/kg to 18.69 MJ/kg. The range of values for the remaining parameters changed slightly, with all meeting the criteria. Application tests showed the generation of waste mixtures with parameters consistent with the established ranges.

Emissions of Volatile Organic Compounds (VOCs) as Safety Indicators in the Development of Wood-Based Binderless Boards

Wood-based panels are ubiquitous in our daily lives, both as building materials and as furnishing materials. Numerous studies have revealed that these materials emit volatile organic compounds, such as formaldehyde, into indoor air, which can be harmful to human health. These volatile organic compounds come both from the wood itself, more specifically cellulose, hemicellulose, and lignin, and from the resins used to bind the wood fibers or particles together. Today, new panels bonded with bio-based adhesives and binderless panels are emerging. The aim of this article is to highlight the importance of measuring VOC emissions from binderless wood-based panels, and more specifically, to identify the VOCs, originating from the wood and thermal transformation processes, likely to be emitted during the production of such panels, as well as how to sample them and measure their emissions. This work provides a useful approach to identifying and quantifying VOC emissions from these new materials. These methodologies should be applied more widely to gain knowledge about VOCs, which are relevant indicators for the development of environmentally friendly materials.

Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture

In order to use high alumina coal gangue as auxiliary cementitious admixture via a simple and convenient thermal activation technique, the thermal transformation, mineral phase transformation and structure changes of coal gangue at calcining temperatures of 500–1000 °C were analyzed using x-ray diffraction (XRD), differential thermal Analysis (DTA), thermogravimetry (TG), infrared analysis (IR) and scanning electron microscope (SEM). The mechanical properties of cement mortar with 30% coal gangue auxiliary cementitious admixture were also measured to determine the optimal calcining temperature. As calcining temperature was increased, the coal gangue experienced the following transformations: carbon combustion, dehydroxylation, metakaolin transformation and mullite transformation. The cement mortar with coal gangue auxiliary cementitious admixture calcined at 700 °C presented the highest 28-d flexural and compressive strength, increasing by 8.27% and 11.85% respectively as compared with the benchmark cement mortar. The maximum dosage of coal gangue auxiliary cementitious admixture in cement mortar was further identified to be less than 30% by mechanical properties testing. The activity of high alumina coal gangues at different calcining temperatures was explained from the view points of hydration degree and products. The present investigation can provide a useful reference to utilize high alumina coal gangue as auxiliary cementitious admixture by means of a simple thermal activation at 700 °C.

Thermal Transformations of Graphite and Anthracite in the Presence of Lithium Carbonate

Thermal Transformations of Graphite and Anthracite in the Presence of Lithium Carbonate

Prospects of oil and gas potential of the South Torgai sedimentary basin

One of the main directions for assessing the prospects of oil production is the study of oils. In this regard, modern geochemical studies are widely used in forecasting the oil and gas potential of the subsurface, occupying an important role in the question of the origin and source of hydrocarbons. The study is aimed at a comprehensive analysis of the geochemical characteristics of the South Torgai sedimentary basin in order to identify and assess the prospects for oil and gas potential. Comparing the composition of oils from different deposits makes it possible to determine the oil source strata, zones of oil formation and oil accumulation. The compounds in oils that are most or least susceptible to changes under the influence of factors such as water leaching, biodegradation and thermal transformation are subject to comparison. The relative content of individual classes of compounds in the oils of the Aryskum trough, the geological characteristics of oil samples and the distribution of normal alkanes are presented. In this work, a comparative analysis of previously conducted geochemical studies was carried out to determine the composition and genesis of oils in the Aryskum trough. Biomarkers in oils, which make it possible to restore the genetic properties of oils and determine the conditions of sedimentation of oil-generating organic substances, indicate the presence of suboxidation conditions, redox potential and predominantly oxidative environment in the process of sedimentation of organic substances. The results obtained are important for understanding the processes of oil formation and generation, as well as for further forecasting the oil content of the South Torgai sedimentary basin.

Hygroscopic Solutes Enable Non‐van der Waals Electrolytes for Fire‐Tolerant Dual‐Air Batteries

AbstractThermal safety issues of batteries have hindered their large‐scale applications. Nonflammable electrolytes improved safety but solvent evaporation above 100 °C limited thermal tolerance, lacking reliability. Herein, fire‐tolerant metal‐air batteries were realized by introducing solute‐in‐air electrolytes whose hygroscopic solutes could spontaneously reabsorb the evaporated water solvent. Using Zn/CaCl2‐in‐air/carbon batteries as a proof‐of‐concept, they failed upon burning at 631.8 °C but self‐recovered then by reabsorbing water from the air at room temperature. Different from conventional aqueous electrolytes whose irreversible thermal transformation is determined by the boiling points of solvents, solute‐in‐air electrolytes make this transformation determined by the much higher decomposition temperature of solutes. It was found that stronger intramolecular bonds instead of intermolecular (van der Waals) interactions were strongly correlated to ultra‐high tolerance temperatures of our solute‐in‐air electrolytes, inspiring a concept of non‐van der Waals electrolytes. Our study would improve the understanding of the thermal properties of electrolytes, guide the design of solute‐in‐air electrolytes, and enhance battery safety.