Acetone Molecules Research Articles

Electrical properties of acetone imprinted hematite nanomaterials doped with Pd & Ag for gas sensing and simulation of their wireless devices

This article presents a novel technique for wireless hydrothermally improved gas sensor devices enhanced by molecular imprinting technique (MIT) for hematite nanomaterials with the existence of acetone using different ratios (10 %, 15 %, and 25 %) as well as doping with palladium/ silver to detect the imprinted gas. α-Fe2O3 are characterized utilizing field emission scanning electron microscope (FESEM), photoluminescence, Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photo-spectroscopy (XPS), and High-Resolution Transmission Electron Microscopy (HRTEM), Thermogravimetric Analysis (TGA) and utilizes Brunauer-Emmett-Teller (BET) to ascertain their shape, optical properties, and values for surface area and thermal characteristics, respectively. Depending on the preparation conditions, non-regular cubes and rods have typical particle sizes ranging from 25 to 120 nm, acetone imprinted and doped with palladium sample (Ap) offers smaller particles than acetone imprinted sample (A15) making adsorption easier. Where XRD showed all diffraction peaks for α-Fe2O3 as well as XPS authorized the oxidation state, also FTIR showed the characteristic peaks of the stretching mode Fe-O which indicates the formation of α-Fe2O3. Lower defects for (Ap) as it has the highest intensity of 176.15 a.u. in the photoluminescent spectrum, for TGA analysis results explain that pure sample has more thermal stability and lower weight loss. Six hematite films are fabricated using the spin coating technique where acetone molecules are presented during the synthesis process of the nanomaterials to imprint their shapes on the surface of hematite. By measuring the response of the gas sensors and their electrical properties, the I-V curve for Ap showed a rectifying behavior and its shunt resistance (Rsh) is higher than series resistance (Rs) which ensures a high response of (115 %). To develop a wireless gas sensor COMSOL Multiphysics software 5.3(a) software is used for the simulation of three devices model by depositing a layer by specified dimensions of hematites (A15, As, and Ap) with their different electrical conductivities on the surface of rectangular patch antenna by showing geometry, the microstrip patch antenna bandwidth, resonant frequency, scattering parameters, and radiation patterns in the E-plane and 3-D far-field pattern and directivity is calculated also, Sp gives improved reflection coefficient, gain quality factor and directivity due to its high electrical conductivity.

Understanding the Adsorption Kinetics of Acetone in Humid Activated Carbons: Perspectives from Adsorption-Breakthrough Experiments and Molecular Simulations.

The presence of water vapor influences the adsorption equilibrium and kinetics of volatile organic compounds (VOCs) in porous materials. By combination of breakthrough experiments and molecular simulations, the competitive adsorption mechanisms of water vapor and acetone on activated carbon with different textures and surface chemical properties at different humidity levels were investigated. Adsorption capacity decreases with increasing relative humidity owing to the formation of preferential adsorption sites between water and the activated carbon surface, while the adsorption rate initially increases and then decreases with increasing relative humidity. Experimental and simulation results revealed that the existence of a small amount of water changed the pore size distributions of activated carbon, thereby promoting the diffusion of acetone molecules. As the relative humidity increased, a portion of the acetone dissolved in water, resulting in a reduction in the adsorption rate. The response of different functional groups to relative humidity was further clarified by molecular simulation. Activated carbons with a high electrostatic interaction with acetone were less affected by humidity and thus exhibit greater potential as adsorbents.

A highly sensitive and fully flexible Fe-Co metal-organic framework hydrogel based gas sensor for ppb level detection of acetone

Most nanomaterials based gas sensors are established on rigid substrates which require operation at elevated temperature and involve long recovery times, thus, limiting their practical applications. Addressing these issues, we demonstrate a fully flexible Fe/Co metal organic framework hydrogel (Fe/Co MOF HG) based gas sensor that detects ultra-low concentrations of acetone at room temperature. This hydrogel is synthesized using optimized concentration (3:1 M ratio) of Co:Fe with benzene dicarboxylic acid (BDC) in Fe/Co MOF via solvothermal method followed by lyophilization. Detailed morphological evaluation reveals 3-dimentional porous structure with multiple voids which largely enhances the specific surface area. Upon exposure to acetone, the Fe/Co MOF HG with Cu metal contacts based sensor exhibits a sensing response (S%) of 12.28 % to 500 ppb of acetone with a wide dynamic range of 200 ppb to 4 ppm. This remarkable sensitivity can be attributed to the abundance of water-adsorbed oxygen (Oc% = 24.58 %) in hydrogel as confirmed by XPS technique, which helps in the increase of the adsorption of a large proportion of acetone molecules on the surface of hydrogel. The limit of detection (LOD = 3σ/s) is found to be 103 ppb which is significantly lower than the other reported MOF-based acetone sensors. Further, the sensor demonstrates excellent selectivity against other common VOCs such as ammonia, benzene, toluene, and formaldehyde. Finally, the sensor’s outstanding stability (upto one-month), mechanical robustness when subjected to 230 cycles of bending and resilience to changes in humidity opens up new possibilities for the use of MOF-based hydrogels as gas sensors in several wearable device domains, such as health care and environmental monitoring.

Interactions between small organic molecules and water measured using pressure perturbation calorimetry

Aqueous liquid mixtures play a critical role in many biological and chemical processes. Solutes including sugars, sugar alcohols, carboxylic acids, alcohols and acetone can affect the hydrogen-bonded structure of water and this can be measured using pressure perturbation calorimetry (PPC). In binary water–solute mixtures, Δ(∂CP/∂P)T is a measure of the structure of the water component. At low alcohol concentrations, negative Δ(∂CP/∂P)T values are consistent with clathrate-like water cages around the alkyl moieties. Conversely, when solutes hydrogen bond with water it interferes in the formation of “ice-like” water and is observable as a positive Δ(∂CP/∂P)T. The Δ(∂CP/∂P)T at increasing concentrations of ethanol, acetone and acetic acid in water displayed very different behaviors. Ethanol–water mixtures had three distinct concentration dependent phases; the first, with ethanol surrounded by water molecules, followed by the ethyl groups self-associating breaking the clathrate-like cages, and the ethanol–water network displacing all of the bulk water. Acetic acid–water mixtures display nonlinearity in Δ(∂CP/∂P)T versus acetic acid concentration consistent with acetic acid self-interaction which interferes with acetic acid capacity to disrupt water structure. Acetone-water mixtures display linearity in Δ(∂CP/∂P)T versus acetone concentration which is consistent with acetone’s inability to hydrogen bond with other acetone molecules. The lack of negative Δ(∂CP/∂P)T values in acetic acid-water and acetone-water mixtures suggests there is sufficient self-association between these solutes to prevent clathrate-like water cage formation. PPC can provide invaluable insight into the behavior of aqueous binary mixtures.

Thermodynamic properties of β-HMX in binary mixed solvent systems and its microscopic mechanisms

Octogen (HMX) is the most powerful military explosive in current use. However, the unclear thermodynamic molecular mechanisms severely limit the development of its production process. In this paper, the solubility of β-HMX in three binary mixed solvent systems (acetone + ethanol, acetone + dichloromethane, acetone + toluene) was measured via a dynamic method at temperature ranging from 283.15 to 313.15 K under atmospheric pressure. The experimental results reveal that the solubility of β-HMX in these binary mixed solvent systems is positively correlated with acetone molar fraction and temperature, and the solvent composition has a greater impact on its solubility compared with the temperature. Moreover, the solubility of β-HMX is further correlated with the Van’t Hoff equation, modified Apelblat equation, CNIBS/R-K model, Jouyban-Acree-Van’t Hoff model, Jouyban-Acree-Apelblat model and NRTL model, and the modified Apelblat equation can give better fitting result (ARD = 8.101 × 10−3, RMSD = 1.065 × 10−5). Finally, the microscopic mechanism of the thermodynamic properties of β-HMX in binary mixed solvents is revealed by investigating the types, intensity and interaction sites of interactions based on density functional theory (DFT) and molecular dynamic (MD) simulation. The results demonstrate that both acetone molecules and ethanol molecules can form certain intermolecular interactions with β-HMX molecules, which are the main driving force of solubilization. In contrast, solvent–solvent interactions have an antagonistic effect on the solubility of β-HMX in mixed solvents. This work can further be informative for researchers in the field of energetic material for the solubility evaluations and provide a reference for the industrial production and performance enhancement of HMX in the future.

The Influence of Acetone on the Kinetics of Water Electrolysis Examined at Polycrystalline Pt Electrode in Alkaline Solution

This study investigated the impact of acetone on the electrochemical behavior of polycrystalline platinum electrodes in 0.1 M NaOH solution, with respect to the kinetics of hydrogen and oxygen evolution reactions (HER and OER) and indirectly to the underpotential deposition of hydrogen (UPDH). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques were employed to analyze these processes for acetone concentrations ranging from 1.0 × 10−6 to 1.0 × 10−3 M. The addition of (CH3)2C=O enhanced the catalytic efficiency of alkaline water splitting, which was believed to be a result of a significant reduction in the surface tension phenomenon (due to mutual interaction of acetone and water molecules), thus considerably facilitating hydrogen bubble detachment from the Pt electrode. Key findings in this work are described with respect to facilitation of both the HER and the OER reactions’ kinetics by the presence of acetone (also undergoing Pt electroreduction over the potential range for UPDH) in the working solution, without an electrode surface poisoning effect. The latter implies significant opportunities for traces of organic additives into alkaline electrolyte to improve the industrial alkaline water electrolysis process.

From Coordination to Noncoordination: Syntheses and Substitution Lability Studies of Titanium Triflato Complexes.

A new concept for obtaining cationic complexes with triflate counteranions from coordinating triflato ligands was developed. Various routes are leading to titanium(IV) and titanium(III) triflato complexes efficiently. The reactions of pentafulvene titanium complexes with either triflic acid or silver triflate give the corresponding titanium(IV) triflato complexes in excellent yields. Hydrolysis of the titanium(IV) bistriflato complexes leads to cationic aqua complexes via displacement of the triflato ligand, which consequently acts as a noncoordinating anion. A functionalized titanium(IV) monotriflato complex was synthesized by insertion of a nitrile into the Ti-C bond and the triflato ligand was displaced by an NHC. While the titanium(IV) complexes are mostly inert toward substrates, the donor-free titanium(III) triflato complex is a strong Lewis acid and forms various adducts with monodentate Lewis bases. The titanium(III) complex was oxidized by reaction with TEMPO, resulting in a diamagnetic titanium(IV) complex. The reaction with bidentate ligands results in cationic titanium(III) complexes due to displacement of the triflato ligand by the bidentate ligands. Treatment with acetone leads to an aldol reaction of two acetone molecules and the formation of a cationic diacetone alcohol complex.

Defect-enabled room-temperature acetone gas sensors based on Zn-doped cauliflower-like bismuth oxide

Metal oxide-based gas sensors have promising advantages, such as low cost and high sensitivities, but the high working temperature (150°C–300 °C) hinders their practical applications. Herein, this study demonstrated a Zinc (Zn)-doped approach to achieve defect-enabled room-temperature acetone gas sensors based on bismuth oxide (Bi2O3) thin film. Through a simple chemical bath deposition method, the varying substitutional doping of zinc (2 wt% to 8 wt%) can induce the morphological transformation of Bi2O3 nanosheets to a cauliflower-like nanostructure, leading to enhanced surface area and active sites. The incorporation of Zn ions can result in oxygen vacancies in the Bi2O3 lattice and the rising of the depletion layer, facilitating the interaction toward acetone molecules at ambient temperatures, leading to an increment of response ∼6. The Zn-doped cauliflower-like Bi2O3 electrode exhibits a superior sensing performance of acetone gas with a low detection limit of 1 ppm and high stability over 90 days. This work underscores the potential of controlled doping of Zn for oxygen vacancy-riched Bi2O3 thin film as a promising room-temperature acetone gas sensor, offering new avenues for the detection of hazardous gases with improved sensitivity.

Experimental investigation on the impact of fuel injection schemes on the fuel/air mixing characteristics in alternating wedge struts

To enhance the performance of scramjet engines, it is essential to understand the fuel/air mixing characteristics downstream of alternating wedge struts and the dynamics of streamwise vortices. Two optical measurement techniques, Mie scattering and acetone-particle laser-induced fluorescence, were employed to study the impact of fuel injection location and different injection gases on the fuel/air mixing characteristics downstream of alternating wedge struts at total temperature of 300 K and total pressure of 800 kPa. The results indicated that the particle laser-induced fluorescence measurements provided superior results compared to Mie scattering, due to the more uniform distribution and better following characteristics of acetone molecules as seeding particles. Different fuel injection locations resulted in varying fuel distributions and plume morphologies downstream. The plume sizes obtained from the three types of fuel orifices were generally consistent, but the mixing effect of the orifices on the first strut was better, whose injection locations being at the trailing edge intersections, with a larger plume area and more uniform fuel distribution. The fuel/air mixing process downstream of the alternating wedge struts was primarily dominated by streamwise vortices. Despite certain differences in the physical properties of nitrogen and hydrogen molecules, the measurement results showed that the plume morphologies obtained with both gases were quite similar. Additionally, a streamwise vortex model was developed to predict the dynamics of streamwise vortices and the evolution of fuel plume morphology, and it was compared with experimental results.

Reactivity of a Linear 2-Germapropadiene with Acids, Ketones, and Amines.

The reactivity of an isolable 2-germapropadiene with acids, ketones, and amines was investigated. The reactions of 2-germapropagiene 1 with hydrogen chloride and acetic acid afforded the corresponding dichlorogermane (2) and diacetoxygermane (3), respectively, indicating that the central germanium atom of 1 is electrophilic. The reaction of 1 with benzaldehyde proceeds via a formal [2+2] cycloaddition to afford the corresponding spiro compound (4). Moreover, 1 reacts smoothly with acetone to furnish germane 5, which contains a six-membered ring involving two acetone molecules. Furthermore, 1 undergoes N-H bond insertion with methylamine or aniline to afford diamino germanes 7 and 8, respectively. The reaction of 1 with urea selectively afforded the corresponding N-H-insertion product (8).

Influence of Accelerated Electron-Irradiation on Sorption Properties of Latvian Darkhead Sheep Wool Fibers

Latvian Darkhead (LD) is a local sheep breed and a genetic resource in Latvia. Preservation and development of the sheep population in the local region is important for the recultivation of fields, it serves as a source for export and local use, as well as waste wool can be applied for developing new products, for example, sorbents for volatile organic pollutants. Therefore, investigation of the sorption properties of the LD sheep wool fibers is under interest. In addition, modification options of the wool for improvement of properties are viewed. Therefore, in the present work, sheep wool fibers as well as accelerated electron-irradiated fibers are analyzed and compared. Fourier transform infrared (FTIR) spectrometry is applied to develop the sorption testing system of volatile organic compounds. An analytical system consisting of a volatile organic compound source, sheep wool filter, and FTIR spectrometry cell is tested and applied for analysis of wool sorption properties for acetone molecules. Registration of the FTIR spectra was performed within the range of 600-4000 cm-1, in the nitrogen flow of about 150mL/min. FTIR analysis shows, that the accelerated electron irradiated sheep wool fibers absorb acetone of about 33% more than non-irradiated fibers. The obtained results will be used for developing recommendations for filter producers to fabricate filter components containing LD sheep wool fibers.

Synthesis, structure and photoluminescence properties of heterometallic-based coordination polymers of trimesic acid.

Reacting trimesic acid (H3TMA, C9H6O6) with CaCl2 and MCl2 at 110 °C under hydrothermal conditions gave the isostructural heterobimetallic coordination polymers (CPs) catena-poly[[tetraaquazinc(II)]-μ-5-carboxybenzene-1,3-dicarboxylato-[tetraaquacalcium(II)]-μ-5-carboxybenzene-1,3-dicarboxylato], [CaZn(HTMA)2(H2O)8]n, 1, and catena-poly[[tetraaquacobalt(II)]-μ-5-carboxybenzene-1,3-dicarboxylato-[tetraaquacalcium(II)]-μ-5-carboxybenzene-1,3-dicarboxylato], [CaCo(HTMA)2(H2O)8]n, 2. Compounds 1 and 2 crystallize in the monoclinic space group C2/c. The solid-state structures consist of eight-coordinate CaII ions and six-coordinate MII ions. These ions are connected by a doubly deprotonated HTMA2- ligand to create a one-dimensional (1D) zigzag chain. Poly[[decaaquabis(μ3-benzene-1,3,5-tricarboxylato)calcium(II)dizinc(II)] dihydrate], {[CaZn2(TMA)2(H2O)10]·2H2O}n, 3, was found incidentally as a minor by-product during the synthesis of 1 at a temperature of 140 °C. It forms crystals in the orthorhombic space group Ccce. The structure of 3 consists of a two-dimensional (2D) layer composed of [Zn(TMA)] chains that are interconnected by CaII ions. The presence of aromatic carboxylic acid ligands and water molecules, which can form numerous hydrogen bonds and π-π interactions, increases the stability of the three-dimensional (3D) supramolecular architecture of these CPs. Compounds 1 and 2 exhibit thermal stability up to 420 °C, as indicated by the thermogravimetric analysis (TGA) curves. The powder X-ray diffraction (PXRD) data reveal the formation of unidentified phases in methanol and dimethyl sulfoxide, while 1 exhibits chemical stability in a wide range of solvents. The luminescence properties of 1 dispersed in various low molecular weight organic solvents was also examined. The results demonstrate excellent selectivity, sensitivity and recyclability for detecting acetone molecules in aqueous media. Additionally, a possible sensing mechanism is also outlined.

Solvent Controlled Generation of Spin Active Polarons in Two-Dimensional Material under UV Light Irradiation.

Polarons belong to a class of extensively studied quasiparticles that have found applications spanning diverse fields, including charge transport, colossal magnetoresistance, thermoelectricity, (multi)ferroism, optoelectronics, and photovoltaics. It is notable, though, that their interaction with the local environment has been overlooked so far. We report an unexpected phenomenon of the solvent-induced generation of polaronic spin active states in a two-dimensional (2D) material fluorographene under UV light. Furthermore, we present compelling evidence of the solvent-specific nature of this phenomenon. The generation of spin-active states is robust in acetone, moderate in benzene, and absent in cyclohexane. Continuous wave X-band electron paramagnetic resonance (EPR) spectroscopy experiments revealed a massive increase in the EPR signal for fluorographene dispersed in acetone under UV-light irradiation, while the system did not show any significant signal under dark conditions and without the solvent. The patterns appeared due to the generation of transient magnetic photoexcited states of polaronic character, which encompassed the net 1/2 spin moment detectable by EPR. Advanced ab initio calculations disclosed that polarons are plausibly formed at radical sites in fluorographene which interact strongly with acetone molecules in their vicinity. Additionally, we present a comprehensive scenario for multiplication of polaronic spin active species, highlighting the pivotal role of the photoinduced charge transfer from the solvent to the electrophilic radical centers in fluorographene. We believe that the solvent-tunable polaron formation with the use of UV light and an easily accessible 2D nanomaterial opens up a wide range of future applications, ranging from molecular sensing to magneto-optical devices.

Deciphering Nitroaromatics Reduction: Theoretical Insights into Dioxomolybdenum Catalysis with Biomass‐Derived Pinacol

AbstractDensity Functional Theory is used to unravel the mechanism of the nitrobenzene to aniline reduction, catalyzed by dioxomolybdenum (VI) dichloride. The use of pinacol as an oxoaccepting reagent and the production of only acetone and water as byproducts, signals a novel and environmentally friendly way to add value to the oxygen‐rich biomass‐derived polyols. The reaction proceeds through three consecutive cycles, each one responsible for one of the three reductive steps needed to yield aniline from nitrobenzene, with nitrosobenzene and hydroxylamine as intermediates. Each cycle regenerates the catalyst and releases one water and two acetone molecules. The mechanism involves singlet/triplet state crossings, a crucial feature in polyoxomolibdate catalyzed processes. The role of the Mo‐coordinated water as the provider of the mysterious protons needed to reduce the nitro group, was revealed. The disclosure of this challenging mechanism and its rate limiting step can contribute to the design of more effective Mo(VI) catalysts.

Boosting acetone response of p-type Co3O4 sensor via Sn and Ni co-doping for diabetes diagnosis

The hole accumulation layer (HAL) configuration of p-type oxides (including Co3O4) in ambient air causes intrinsically low gas response and hinders their promising applications in exhaled gas analysis. Herein, Sn and Ni co-doping has been proposed to trigger the response of chemiresistive Co3O4 sensor toward acetone (biomarker of diabetes). Via incorporating 1 at% Sn and 0.5 at% Ni doping (Co2.95Sn0.03Ni0.02O4), the response to 100 ppm acetone has been boosted ∼2 orders (from 1.24 to 125.6) at 70 °C, the limit of detection (LoD) has been reduced ∼4 times (from 47.9 to 12.4 ppb), the optimal operation temperature has been decreased from 130 °C to ∼70 °C. Various characterizations suggest that co-doping induced abundant surface asymmetric oxygen vacancy defects (Co-□-Ni, Sn-□-Ni), which facilitate the catalytic oxidation of acetone molecules at relatively low operation temperature. In addition to excellent reproducibility and long-term stability, Co2.95Sn0.03Ni0.02O4 sensor could also operate under highly humid air background and reliably detect acetone concentration in exhaled breath at 150 °C, opening the opportunity for the practical application of p-type oxide sensors for diabetes diagnosis.

Ultrathin Langmuir-Blodgett film of functionalized single-walled carbon nanotubes for enhanced acetone sensing

Acetone is one of the important volatile organic compounds which needs to be detected from the industrial effluent and as a bio-marker from breath of diabetic patients. Here, ultrathin Langmuir-Blodgett (LB) film of octadecylamine- functionalized single-walled carbon nanotubes (ODA-CNT) was formed on interdigitated gold electrodes and was employed for acetone vapor sensing using the impedance spectroscopy (IS) at room temperature. The LB film deposited in liquid-like phase of the Langmuir monolayer of ODA-CNT revealed aligned nanotubes. Being a reducing agent, acetone interacts readily with the CNTs through the transfer of electrons. Using IS, multiparameter were measured with respect to both frequency and acetone vapor concentration. Principal component analysis (PCA) of the IS data revealed capacitance as the most suitable parameter for acetone vapor sensing using the ODA-CNT film. A very low limit of detection (0.5 ppm) and a wide detectable concentration range (1–300 ppm) for acetone sensing using the LB film of ODA-CNT was obtained. The 2D calibration map revealed that the sensing performance of acetone using LB film was much better as compared to that of drop-cast film of ODA-CNT and LB film of pristine CNTs. The superior sensing performance of the LB film of ODA-CNT is attributed to the uniform and aligned nature of the nanotubes, leading to a coherent behavior due to interaction with the acetone molecules. This study shows the potential of LB films of ODA-CNT for sensitive and low level detection of acetone vapor at room temperature.

Anionic Hydrogen-Bonded Frameworks Showing Tautomerism and Colorful Luminescence for the Ultrasensitive Detection of Acetone.

Tautomers coexisting in an equilibrium system have significant potential for regulating luminescent properties because of their structural differences. However, separating and stabilizing tautomers at room temperature is a considerable challenge. In this study, it is found that hydrogen-bonded organic frameworks (HOFs) composed of Br- anions can effectively separate and stabilize two proton-transfer tautomers of triarylformamidinium bromide: namely, the nitrogen cation (BA-N) and carbon cation (BA-C). The BA-N crystal consisting of a dense anionic HOF and parallelly aligned organic cations exhibits green thermally activated delayed fluorescence and red room-temperature phosphorescence (RTP). The BA-C crystal contains acetone molecules that induce an antiparallel arrangement of the organic cations to form a loose HOF, producing blue prompt fluorescence and green RTP. Interestingly, switching of the HOFs between BA-N and BA-C can be achieved through the uptake and release of acetone, thereby dynamically adjusting multiple luminescent properties. Consequently, the HOF crystals can be used for the highly sensitive and specific sensing of acetone with a detection limit of 66.74 ppm. This study not only stabilizes tautomeric luminescent materials at room temperature, but also provides a new method for constructing smart HOFs with a sensitive response to a stimulus.

Anionic Hydrogen‐Bonded Frameworks Showing Tautomerism and Colorful Luminescence for the Ultrasensitive Detection of Acetone

AbstractTautomers coexisting in an equilibrium system have significant potential for regulating luminescent properties because of their structural differences. However, separating and stabilizing tautomers at room temperature is a considerable challenge. In this study, it is found that hydrogen‐bonded organic frameworks (HOFs) composed of Br‐ anions can effectively separate and stabilize two proton‐transfer tautomers of triarylformamidinium bromide: namely, the nitrogen cation (BA‐N) and carbon cation (BA‐C). The BA‐N crystal consisting of a dense anionic HOF and parallelly aligned organic cations exhibits green thermally activated delayed fluorescence and red room‐temperature phosphorescence (RTP). The BA‐C crystal contains acetone molecules that induce an antiparallel arrangement of the organic cations to form a loose HOF, producing blue prompt fluorescence and green RTP. Interestingly, switching of the HOFs between BA‐N and BA‐C can be achieved through the uptake and release of acetone, thereby dynamically adjusting multiple luminescent properties. Consequently, the HOF crystals can be used for the highly sensitive and specific sensing of acetone with a detection limit of 66.74 ppm. This study not only stabilizes tautomeric luminescent materials at room temperature, but also provides a new method for constructing smart HOFs with a sensitive response to a stimulus.

Ni(II)-Metal-organic framework based on 3,3′-di(1H-imidazol-1-yl)-1,1′-biphenyl: Synthesis, structure and luminescence detection

A new metal–organic framework material [Ni(L)(pda)(H2O)2]•2H2O (1) was synthesized by a solvothermal reaction of 3,3′-di(1H-imidazol-1-yl)-1,1′-biphenyl (L) and 1,4-Phenylenediacetic acid (H2pda) with Ni(NO3)2·6H2O. Crystal properties were characterized by elemental analysis (ER), infrared spectroscopy (IR), thermogravimetric analysis (TGA), and powder X-ray diffraction (PXRD), and it was found that 1 has excellent thermal and structural stability. Furthermore, through fluorescence luminescence experiments, 1 exhibits excellent recognition performance for antibiotics, Fe3+, Cr(Ⅵ) and acetone molecules, which has potential application value.

Development of B3O3 monolayer as a highly sensitive sensor for detection of acetone molecule: A DFT analysis

The world witnessed significant economic growth due to the rapid recovery of businesses and industries in the post-epidemic era. Nonetheless, the problems of the emission of harmful gases, with all its attendant dangers, have recently attracted considerable attention. Using effective methods to accurately monitor these harmful gases is the first thing to be done for solving these problems. Within this work, by means of the first-principles density functional theory, a B3O3 monolayer (B3O3ML) gas sensor was introduced in order to monitor the harmful gas acetone (ACT). The negative adsorption energies of the complex of ACT/B3O3ML demonstrated that adsorption of the ACT molecules over the B3O3ML was favorable in terms of energy and the process of adsorption was exothermic. After the adsorption of ACT on the surface of the B3O3ML, there were noticeable changes in the electronic properties of ACT and in the density of sates. The recovery time of the B3O3ML for the detection of the ACT molecule was estimated to be 2.07 × 10−5 s, suggesting the rapid regeneration of the sensor at room temperature. Hence, the B3O3ML is a promising candidate for detecting the ACT molecule and will inspire experimentalists to design an efficient gas sensor.