Conductivity Of Ionic Liquids Research Articles

MOF for encapsulating ionic liquids serves as an electrocatalyst to decrease the ignition delay time of electrically controlled solid propellants

Electrically controlled solid propellants (ECSPs) have the characteristics of adjustable thrust and multiple start-stop, but they also encounter the challenge of a prolonged ignition delay time. Two metal–organic frameworks (MOFs) including Ni-MOF and IL@Ni-MOF, were synthesized as electrocatalysts to enhance the electrical response of the propellant with little variation of thermal decomposition response. The structure and characteristics of both materials were analyzed, and the impact on the ignition delay time of the ECSP was assessed. The results revealed that a highly conductive ionic liquid is encapsulated within Ni-MOF to alleviate the issue of low conductivity caused by the large pores of the Ni-MOF. This encapsulation leads to the shortest ignition delay time for propellants containing IL@Ni-MOF compared with the propellants without catalyst and containing Ni-MOF. Specifically, when the concentration of IL@Ni-MOF reached 1.5%, the ignition delay decreased by 80% compared with the propellants without catalyst.

Multiple Noncovalent Binding in the Intermediates and Products of the Reaction of <i>N,N</i>-Dimethylformamide with Bromine

Reaction of nonionic N,N-dimethylformamide (DMF) with bromine under controllable conditions leads to a number of ionic compounds, mainly to bis(N,N-dimethylformamide)hydrogen dibromobromate. Computations with DFT (ωB97xV/dgdzvp) were made for geometry, thermochemistry and electron configuration of products and supposed intermediates. Two labile particles [bis(N,N-dimethylformamide)hydrogen cation and dibromobromate-anion] form stable highly conductive ionic liquid that can be distilled in vacuo without losses or decomposition. A number of molecular complexes of DMF with bromine and water presumed to be intermediates of this reaction. It is a set of halogen and hydrogen bonding that provide an intramolecular binding in these complexes.

Low viscosity and highly flexible stereolithographic 3D printing resins for flexible sensors

Flexible sensors show the wide range of applications in electronic products. However, challenges remain in developing sensors with internal complex construction, excellent flexibility, elasticity and strength. In this paper, a prepolymer (PU-PDMS-OH-HEMA) contain polyurethane (PU) segments and polysiloxane (PDMS) segments was synthesized, and the photosensitive resins with low viscosity for 3D printing were prepared by mixing prepolymers with diluents and photoinitiators. The resultant cured photosensitive resins showed the improved mechanical properties. The PDMS-OH-30 sample exhibit the excellent mechanical properties, with tensile strength and elongation at break of 10.03 MPa and 1046.15 %, respectively, and the resin viscosity of 62 cP. Conductive ionic liquids were added to the above photosensitive resins to prepare flexible sensors, which show the electrical sensitivity and stability. The findings in the work propose a contribution to the development of highly flexible 3D printing resins for fabricating flexible sensors.

High‐accuracy dynamic gesture recognition: A universal and self‐adaptive deep‐learning‐assisted system leveraging high‐performance ionogels‐based strain sensors

AbstractGesture recognition utilizing flexible strain sensors is a highly valuable technology widely applied in human–machine interfaces. However, achieving rapid detection of subtle motions and timely processing of dynamic signals remain a challenge for sensors. Here, highly resilient and durable ionogels are developed by introducing micro‐scale incompatible phases in macroscopic homogeneous polymeric network. The compatible network disperses in conductive ionic liquid to form highly resilient and stretchable skeleton, while incompatible phase forms hydrogen bonds to dissipate energy thus strengthening the ionogels. The ionogels‐derived strain sensors show highly sensitivity, fast response time (<10 ms), low detection limit (~50 μm), and remarkable durability (>5000 cycles), allowing for precise monitoring of human motions. More importantly, a self‐adaptive recognition program empowered by deep‐learning algorithms is designed to compensate for sensors, creating a comprehensive system capable of dynamic gesture recognition. This system can comprehensively analyze both the temporal and spatial features of sensor data, enabling deeper understanding of the dynamic process underlying gestures. The system accurately classifies 10 hand gestures across five participants with impressive accuracy of 93.66%. Moreover, it maintains robust recognition performance without the need for further training even when different sensors or subjects are involved. This technological breakthrough paves the way for intuitive and seamless interaction between humans and machines, presenting significant opportunities in diverse applications, such as human–robot interaction, virtual reality control, and assistive devices for the disabled individuals.

Self‐Adhesive, Detach‐on‐Demand, and Waterproof Hydrophobic Electronic Skins with Customized Functionality and Wearability

AbstractThe interfacial design of the electronic skins (E‐skins), which are increasingly crucial in areas like exercise monitoring, healthcare, etc., has a great impact on wearability and functions. The adhesion between E‐skin and human skin serves as the foundation for various functionalities. In addition to robust adhesion strength, detaching‐on‐demand, and waterproof abilities are also important for long‐time wearing and comfort detachment after use. Here, self‐adhesive, detach‐on‐demand, and waterproof hydrophobic E‐skins (PBIA) by copolymerization of acrylates with conductive ionic liquid and adhesive components as the strain sensor and triboelectric nanogenerator (TENG) is developed. The strong van der Waals self‐adhesion (shear adhesion of ≈574 kPa, peeling adhesion of ≈110 N m−1), and waterproof abilities under immersing, flushing, and penetrating situations enable the E‐skin to realize stable and long‐time monitoring for body motions in both the resistance sensing and TENG modes. Meanwhile, the easy detach‐on‐demand ability of van der Waals adhesion (574 to 35 kPa and 110 to 7 N m−1) guarantees the easy and comfortable detachment of PBIA after use, avoiding pain or injury to the skin. The adhesion strategy of PBIA can be expanded to other kinds of E‐skins and accelerate the pace of practical applications of E‐skins.

Rapid Radiation Synthesis of a Flexible, Self-Healing, and Adhesive Ionogel with Environmental Tolerance for Multifunctional Strain Sensors.

Ionogels are increasingly used in flexible strain sensors, but it is still challenging to incorporate multifunctional properties such as flexibility, self-healing, adhesion, temperature resistance, and electrical conductivity. Herein, a facile and rapid one-step photoinitiated polymerization strategy is employed to prepare multifunctional ionogels by filling a hydrophobic and conductive ionic liquid into a flexible, hydrophobic fluoropolymer matrix. Thanks to the presence of abundant noncovalent interactions (hydrogen-bonding and ion-dipole interactions), the ionogels exhibit high transparency, excellent mechanical properties, self-healing ability, and adhesion. Moreover, rich C-F bonds in the fluoropolymer matrix can eliminate the interference of water molecules, resulting in excellent environmental tolerance such as high and low temperature resistance, waterproofness, and anticorrosion. Furthermore, the ionogel-based wearable strain sensor can sensitively detect and differentiate human movements and subtle muscle movements and serve as a Morse code signal transmitter for information transmission. The presented work provides an effective method to develop versatile flexible conductive ionogels for wearable devices and ionotronics.

The effect of the mantle and core matter phase state on the course of geodynamic processes

The study of the course of geodynamic processes in the lower crust and upper mantle proves that an additional energy contribution is made by a change in the phase state of matter with increasing pressure and temperature. The gas phase, composed of hydrogen, oxygen and carbon, turns into a fluid that combines the properties of a liquid and a gas. The result is a change in the behavior of fluid-crystal and fluid-melt systems which significantly accelerates melting and physicochemical interactions in the thermal asthenosphere. These conclusions are confirmed by numerous experimental studies and the results of the study of xenoliths representing the crust and mantle of cratons and active regions.
 Seismic tomography studies show distinct patterns of inhomogeneities in physical pro­per­ties, reflecting inhomogeneities in the mantle structure. Many works hypothesize, with substantiation, that plumes or fluid flows arise at the boundary of the core and mantle and are factors of all geodynamic processes. Modern ideas about the composition of the Earth's core are based on the statement that it is composed of molten iron with minor impurities of other elements. However, calculations of the energy balance and physical modeling of the redistribution of matter in the core itself show that the removal of volatile components or convective currents do not provide enough energy for the formation of plumes.
 The assumption that the substance of the core is an electrically conductive ionic liquid in which chemical compounds have completely dissociatedand the electronic structure has no gapradically changes the idea of the energetics of the core and the possibility of initiating plume processes. The properties of a substance in a similar phase state are fundamentally different from the properties of a liquid.

State of the Art in Industrial Application of Amino-1,2,4-Triazoles

Abstract: The review summarizes information on the industrial use of 3- and 4-amino-1,2,4-triazoles, the basic raw material for the industry of fine organic synthesis. A description of the existing production methods for the synthesis of 3- and 4-amino-1,2,4-triazoles and some methods of obtaining in laboratory conditions is given. Three main areas of use of these amines and their derivatives have been identified: agriculture, medicine, high-energy substances and gas-generating compositions. It has been shown that one of the earliest areas of widespread use of 3- and 4-amino-1,2,4-triazoles is the production of plant protection products. On their basis, the mass production of various insecticides, fungicides, plant growth regulators, retardants and inhibitors of nitrification of nitrogen fertilizers has been organized. The use of these amines in medicine consists in the production of known drugs on their basis, such as furazonal, thiotriazoline and cardiotril, which have hepatoprotective, antioxidant and anti-ischemic activity. The industrial processing of 3- and 4-amino-1,2,4-triazoles into explosives, solid propellants, propellants, and gas-generating compositions is a third well-known field of application. An explanation is given for the high reactivity of amines and the variety of areas of their use. A significant place in the review is occupied by the analysis of less known directions of use of the indicated aminotriazoles. These are: obtaining new types of salts and electrically conductive ionic liquids, corrosion inhibitors of non-ferrous metals and catalysts for the curing of epoxy resins. The results of recent studies are discussed, and the prospects for the use of 3- and 4-amino-1,2,4-triazoles as raw materials for the production of new reagents in analytical chemistry, proton-exchange membranes, and new condensed nitrogen-containing heterocycles are shown.

Diradicaloid Strategy for High‐Efficiency Photothermal Conversion and High‐Sensitivity Detection of Near Infrared Light

AbstractOrganic molecules are promising near infrared (NIR) photothermal materials because of their structural flexibility and fine‐tuned properties. However, weak NIR absorption and strong fluorescence character lead to low photothermal conversion efficiency (PCE). Herein, NIR quinoidal diradicaloids are designed and synthesized by a heteroaromatic‐bridged Blatter radical strategy. Benefiting from the relatively planar framework and diradical character, these singlet diradicaloids exhibit strong and broad absorption in the NIR region (750–1100 nm) in both solution and aggregate states, which do not show any fluorescence. High PCE up to 71.4% is evaluated under 808 nm laser. On this basis, a NIR detector employing a blend of the diradicaloids and conductive ionic liquid is fabricated, yielding a remarkably high thermal response of 1100% at 0.5 W cm−2. This work reveals that π‐conjugated diradicaloids are promising candidates for NIR detection.

Fabrication of high-quality microcapsules containing ionic liquid for application in self-healing conductive materials

Conductive materials inevitably develop micro-cracks during processing or use, which seriously impairs the performance and lifetime of their associated devices. Autonomous recovery of conductivity can greatly improve in-service reliability and extend service life. Herein, microcapsules containing conductive ionic liquid (IL) were successfully synthesized using a novel microencapsulation technique via integrating electrostatic spraying and interfacial polymerization (ES-IP), and their high potential for conductivity restoration of conductive pastes for printed circuits was verified. The prepared ionic liquid microcapsules (IL-MCs) have good dispersibility, great solidity, and tunable properties. Self-healing conductive composites were prepared by incorporating the synthesized microcapsules into the conductive slurry and the effect of microcapsule content in the matrix on the restoration was investigated. The conductivity recovery tests show that IL-MCs recover the conductivity of the damaged samples with an efficiency of about 96%. While the restoration efficiency remains essentially stable with increasing the microcapsule content, the chance of restoration increases. When the microcapsule content was 20%, the probability of the damaged samples being autonomously repaired is about 84%. It proves that the successful microencapsulation of IL using the ES-IP technique broadens the applications of ILs in conductive materials.

Design of healable, porous polyurethane with large ionic liquids loading amounts towards ultra-durable pressure sensor

Flexible intelligent sensors have got booming development over the past decades, yet, it is still a huge challenge to construct advanced sensors with long service life and superb durability. Herein, a novel porous capacitance pressure sensor with ultra-durability via sugar template method was prepared successfully by impregnating non-volatile, highly conductive ionic liquids (ILs) into polyurethane (PU-DBTDA5) matrix. As a consequence of the rich hydrogen bonding networks and dynamic hindered urea bond in the polymer chain, the as-prepared PU-DBTDA5 matrix shows excellent self-healing ability (99 %). The ionic liquid-soluble polyethylene glycol (PEG1000) serving as soft segment endows PU-DBTDA5 with ultra-absorption ability of ILs (absorbing ILs over three times to its own weight within 5 min). The pressure sensor with porous structure shows outstanding anti-fatigue ability as well as good sensitivity (S1 = 0.82 kPa−1, S2 = 1.04 kPa−1), and it can even monitor tiny strain as low as 0.5 %. More importantly, due to the well combination of the PU-DBTDA5 with excellent self-healing ability and the non-volatile ionic liquids, not only the healed sensor, but the sensor stored at room environment over 100 days both exhibit stable electronic signals similar to that of freshly-prepared foam sensor in 3000 uninterrupted compression tests, being strong evidence of its ultra-durability.

Electrospray beam currents in the cone-jet mode based on numerical simulation

Electrospray technology is widely used in many technological areas. The beam current of electrospray is an important parameter since it directly associates with the electrohydrodynamic behavior of the cone jet and can be precisely measured. Although how the beam current changes with other variables has been theoretically and experimentally researched, the accurate prediction of the current is still difficult. Particularly, for liquids with high electrical conductivity, Ohmic conduction is a major component of the beam current, but it is ignored in many theoretical models. In this study, the beam current components are investigated via numerical simulation developed based on hydrodynamics and electrostatics equations. Consideration of both convection and conduction currents of the cone jet affords a more accurate calculation of the total beam current. Moreover, an interpolation method is employed to solve the charge “escape” problem, providing a more accurate calculation of charges as well as the currents. The results of the numerical model are validated against experimental results, showing good agreement regarding the meniscus shape and droplet diameters. For a highly conductive ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide, the simulated beam current also shows good agreement with the experimental data, with a maximum error of 13%. Using the improved simulation model, temperature-induced beam current fluctuations are investigated to understand how an electrospray thruster behaves with temperature variations.

Dual‐Enhanced Effect of Ionic Liquid Incorporation on Improving Hybrid Harvesting Properties of Solar and Raindrop Energy

AbstractUbiquitous environmental energy has become an important energy source for ensuring long‐lasting operation of unattended monitoring systems. However, several technical bottlenecks remain for achieving improved collection performance of environmental energy. Herein, a transparent composite film comprising micro‐pyramid arrays (mp‐arrays) and a conductive ionic liquid (IL) based on polydimethylsiloxane (PDMS) is innovatively generated as a difunctional layer that acts as an antireflective coating for solar cells and an enhanced triboelectric layer for the raindrop‐harvesting triboelectric nanogenerator (RH‐TENG). The regular mp‐arrays fabricated using the template transfer technology according to the matched refractive index between IL and PDMS effectively inhibit the surface reflection and improve the light trapping ability of solar cells. Owing to a significant increase in transmittance, the power conversion efficiency of the solar cell is enhanced by 10.92% owing to the IL@PDMS coating with mp‐arrays (mp‐IL@PDMS). Further, the conductive IL significantly improves the dielectricity of PDMS film. Due to the improved dielectric constant, increased aspect ratio, and excellent hydrophobicity, the output voltage and current of the RH‐TENG with mp‐IL@PDMS are enhanced by ≈24‐ and 44‐fold, respectively. Overall, this study, which is based on the incorporation of transparent conductive IL, provides a new technical path for efficient multiclimate energy harvesting.

Ultra-High Electrical Conductivity in Filler-Free Polymeric Hydrogels Toward Thermoelectrics and Electromagnetic Interference Shielding.

Conducting hydrogels have attracted much attention for the emerging field of hydrogel bioelectronics, especially poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) based hydrogels, because of their great biocompatibility and stability. However, the electrical conductivities of hydrogels are often lower than 1 S cm-1 which are not suitable for digital circuits or applications in bioelectronics. Introducing conductive inorganic fillers into the hydrogels can improve their electrical conductivities. However, it may lead to compromises in compliance, biocompatibility, deformability, biodegradability, etc. Herein, a series of highly conductive ionic liquid (IL) doped PEDOT:PSS hydrogels without any conductive fillers is reported. These hydrogels exhibit high conductivities up to ≈305 S cm-1 , which is ≈8 times higher than the record of polymeric hydrogels without conductive fillers in literature. The high electrical conductivity results in enhanced areal thermoelectric output power for hydrogel-based thermoelectric devices, and high specific electromagnetic interference (EMI) shielding efficiency which is about an order in magnitude higher than that of state-of-the-art conductive hydrogels in literature. Furthermore, these stretchable (strain >30%)hydrogels exhibit fast self-healing, and shape/size-tunable properties, which are desirable for hydrogel bioelectronics and wearable organic devices. The results indicate that these highly conductive hydrogels are promising in applications such as sensing, thermoelectrics, EMI shielding, etc.

Improvement of safe bromine electrolytes and their cell performance in H2/Br2 flow batteries caused by tuning the bromine complexation equilibrium

Hydrogen bromine redox flow batteries utilize bromine electrolytes in their positive half cell, offering capacities larger than 100 Ah L −1 . Addition of quaternary ammonium compounds, so-called bromine complexing agents (BCA), may increase safety as they reduce the vapour pressure of bromine in the posolyte. However, they have not been applied so far. They (a) interact with perfluorosulfonic acid membranes leading to significant reduction of membrane conductivity and (b) they form a low conductive ionic liquid with polybromides, leading to high overvoltage if the formation happens at the electrode. In this work a solution to this problem is proposed by an excess addition of Br 2 to these electrolytes. The excess bromine leads to a permanent bromine fused salt phase in the tank. Bromine formed in the cell stays in the aqueous phase and bromine transfer between the two phases happens in the tank. Transfer of Br 2 without the transfer of [BCA] + cations exists between the phases, while [C2Py] + cations remain in the fused salt and do not influence cell performance. For the first time a posolyte capacity of 179.6 Ah L −1 based on 7.7 M hydrobromic acid with BCA is achieved compared to previous investigations with e.g. 53.9 Ah L −1 . • Evaluation of bromine posolytes with complexing agents (BCA) for energy storage. • Investigation of Br 2 transfer mechanism between aqueous electrolyte and fused salt. • Successful development of electrolyte by intervention in complexation reaction. • Reduced influence of BCA cation on PFSA membrane performance and cell performance. • Increase of the useable electrolyte capacity from 53.9 Ah L −1 to 179.6 Ah L −1 .

Highly Sensitive Flexible Pressure Sensors Enabled by Mixing of Silicone Elastomer With Ionic Liquid-Grafted Silicone Oil.

Developing highly sensitive flexible pressure sensors has become crucially urgent due to the increased societal demand for wearable electronic devices capable of monitoring various human motions. The sensitivity of such sensors has been shown to be significantly enhanced by increasing the relative dielectric permittivity of the dielectric layers used in device construction via compositing with immiscible ionic conductors. Unfortunately, however, the elastomers employed for this purpose possess inhomogeneous morphologies, and thus suffer from poor long-term durability and unstable electrical response. In this study, we developed a novel, flexible, and highly sensitive pressure sensor using an elastomeric dielectric layer with particularly high permittivity and homogeneity due to the addition of synthesized ionic liquid-grafted silicone oil (denoted LMS-EIL). LMS-EIL possesses both a very high relative dielectric permittivity (9.6 × 105 at 10−1 Hz) and excellent compatibility with silicone elastomers due to the covalently connected structure of conductive ionic liquid (IL) and chloropropyl silicone oil. A silicone elastomer with a relative permittivity of 22 at 10−1 Hz, Young’s modulus of 0.78 MPa, and excellent homogeneity was prepared by incorporating 10 phr (parts per hundreds rubber) of LMS-EIL into an elastomer matrix. The sensitivity of the pressure sensor produced using this optimized silicone elastomer was 0.51 kPa−1, which is 100 times higher than that of the pristine elastomer. In addition, a high durability illustrated by 100 loading–unloading cycles and a rapid response and recovery time of approximately 60 ms were achieved. The excellent performance of this novel pressure sensor suggests significant potential for use in human interfaces, soft robotics, and electronic skin applications.

Deep eutectic solvents based on L-Arginine and glutamic acid as green catalysts and conductive agents for epoxy resins

Many engineered epoxy products in the recent years require sustainable materials to be contributive in the coming decades. The efficiency of [DES]Arg/Eg and [DES]Glu/Eg deep eutectic solvents (DESs) on the curing reaction of bisphenol A diglicydyl ether (DGEBA) with the application of differential scanning calorimetry (DSC) at temperatures 313–333 K is assessed. The both DESs studied here can act as the catalyst of epoxy-amine reaction, hardener and conducting agents in a simultaneous manner. Moreover, it reveals different reaction kinetics which strongly depend on the type of hydrogen bonding acceptor of the mixture. It is observed that there exist many fundamental differences between the progress of isothermal curing reaction in the presence of [DES]Arg/Eg and [DES]Glu/Eg considering the conductive ionic liquids and non-conductive conventional hardeners. The [DES]Glu/Eg at lower concentrations exhibits different catalytic behavior in the initial stages of the reaction, in a sense that the reaction progresses at higher rates up to 5 min and hampered afterward. In contrast, [DES]Arg/Eg act as a high-efficient catalyst in a sense that it allows the curing reaction approaches the completion level within 30 min which is comparable to previously reported conducting dopants. From kinetic results it is deduced that the mechanism of curing reaction follows the first-order kinetic in the presence of [DES]Arg/Eg and [DES]Glu/Eg and reaction occurring in the presence of [DES]Glu/Eg is characterized by higher activation energy compared to [DES]Arg/Eg. To analyze the efficiency of DESs as a catalyst for the epoxy-amine reaction, a computational study is run on a simplified model reaction catalyzed by [DES]Glu/Eg revealing a significant decrease in activation energy of the catalyzed reaction.

Postsynthetic-Modified PANI/MOF Composites with Tunable Thermoelectric and Photoelectric Properties.

A 3D Co-based metal-organic framework (Co-MOF) with two kinds of large pores filled by free Co2+ ions and ligands was synthesized and characterized. To expand the MOF structure and conductivity, the free Co2+ ions and ligands were exchanged by conductive ionic liquid EtpyBr and photosensitive AgNO3 through single crystal-to-single crystal transformation, which produced structure-changed 3D MOFs Co-MOF-Br and Co-Ag-MOF, which were characterized by single-crystal X-ray diffraction. Incorporating small quantities of doped polyaniline (PANI) with redox activity into the pores could further tune the stability and conductivity of the three MOFs. The PANI/MOFs all show outstanding electrical conductivity (≈10-2 S cm-1 ), and PANI/Co-MOF-Br has the largest p-type Seebeck coefficient of 66.6 μV K-1 . PANI/Co-MOF-Br and PANI/Co-Ag-MOF have 4 and 15 times higher photocurrent density compared with PANI/Co-MOF, respectively. This work sheds light on the design of advanced electrically conductive 3D MOFs.

Highly Conductive Ionic Liquid Electrolytes for Potassium-Ion Batteries

Potassium-ion batteries (K-ion batteries; KIBs) are attractive as high-voltage, low-cost energy storage devices. Ionic liquids (ILs) are potential candidates as safe and high-performance electrolytes for large-scale devices. Imidazolium-based ILs are known to possess high ionic conductivities and moderate electrochemical stabilities. In this study, we report the physicochemical and electrochemical properties of K[FSA]–[C2C1im][FSA] (FSA = bis(fluorosulfonyl)amide; C2C1im = 1-ethyl-3-methylimidazolium) ILs as new electrolytes for KIBs. A phase diagram constructed from differential scanning calorimetry results indicates that the melting point of this IL is below 273 K at compositions of x(K[FSA]) = 0–0.20 (x(K[FSA]) = molar fraction of K[FSA]). The viscosity, ionic conductivity, and density of the IL were measured for x(K[FSA]) = 0–0.20. The ionic conductivity at x(K[FSA]) = 0.20 is 10.1 mS cm–1 at 298 K, which is comparable to that of typical organic solvent-based KIB electrolytes and higher than that of other ionic liquid electrolytes for KIBs. The electrochemical stability of M[FSA]–[C2C1im][FSA] (x(M[FSA]) = 0.20; M = K, Na, and Li) ILs was determined by cyclic voltammetry measurements. The K-based IL exhibits the widest electrochemical window of 5.19 V due to the negative redox potential of the K+/K couple. Thus, the K[FSA]–[C2C1im][FSA] ionic liquid is expected to be a highly conductive KIB electrolyte.

Photo-thermal converting polyaniline/ionic liquid inks for screen printing highly-sensitive flexible uncontacted thermal sensors

Flexible sensors are important candidates for future artificial intelligent devices and wearable electronics. Among the methods for the production of flexible sensors, printing has attracted increasingly more attention due to its precision and good reproducibility. In this work, conductive thermo-responsive inks were prepared by the combination of photo-thermal converting eigenstate polyaniline (PANI) and conductive ionic liquids (ILs) in response to temperature. These PANI/ILs inks can be easily screen printed onto various flexible substrates such as A4 paper, fabrics, and plastics to prepare flexible thermal sensors. Under a near infrared (NIR) irradiation such as an 808 nm light source without contact, the PANI absorbed the NIR irradiation and the temperature of the sensor chip was elevated. As a result, the ILs exhibited changes in conductivity and realized the thermo-sensitivity of the PANI/ILs-based chip. These low-cost, easy-to-handle conductive thermo-responsive PANI/ILs inks are good candidates for the preparation and production of flexible thermal sensors.