Detection Of CO Research Articles

Ni-Decorated ZnO Monolayer for Sensing CO and HCHO in Dry-Type Transformers: A First-Principles Theory

This work implements first-principles simulations in order to investigate the Ni-decorating property on the ZnO monolayer and the sensing property of the Ni-decorated ZnO (Ni–ZnO) monolayer upon CO and HCHO molecules formed in the dry-type transformers. The results reveal that the Ni dopant is stably anchored on the TO site of the ZnO surface forming the Ni–Zn and Ni–O bonds with the binding energy (Eb) of −1.75 eV. Based on the adsorption energy (Ead) of −1.49 and −2.22 eV for CO and HCHO on the Ni–ZnO monolayer, we determined the chemisorption for two such systems. The band structure (BS) and atomic density of state (DOS) of the gas adsorbed systems are analyzed to comprehend the electronic property of the Ni–ZnO monolayer in the gas adsorptions. Besides, the change of bandgap and work function uncover the sensing potential of Ni–ZnO monolayer upon CO and HCHO detections, with admirable electrical response (15,394.9% and −84.6%). The findings in this work manifest the potential of Ni–ZnO monolayer for CO and HCHO sensing to evaluate the operation condition of the dry-type transformers.

Study on Photoacoustic Spectroscopy Detection of CO in Gas Insulation Equipment

The related regulations for electric power industry stipulate that CO gas is an important component to be detected when analyzing the gas composition of SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> equipment. In this study, based on the photoacoustic spectroscopy technology, the quantitative gas detection of CO is carried out. First, in order to avoid the cross-interference effects of other component gases on photoacoustic spectroscopy detection of CO, the characteristic absorption spectrum of CO in 4291.5 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> (whose wavelength is 2330.2 nm) is determined. Second, the nonresonant photoacoustic cell is optimized in this study. After that, designing and building a trace gas photoacoustic spectroscopy detection platform around the developed photoacoustic cell, using the built detection platform to perform photoacoustic spectroscopy detection of the concentration of CO, and obtaining photoacoustic signals of different concentrations of CO, the photoacoustic signals increase linearly as the concentration increases. With SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> as the background gas, the lower detection limit of CO gas reaches 20.5 ppm, and with N <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> as the background gas, it reaches 5.6 ppm. After all, the influence mechanism of the background gas on the photoacoustic signal is studied, and based on the influence mechanism, the lower detection limit of CO with the background gas of different mixing ratios of SF <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> /N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> is predicted. The verified experiment is basically consistent with the predicted results, which proves the accuracy of the forecast. This study provides guidance for the engineering application of CO photoacoustic spectroscopy detection in SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> equipment.

Molecular tracers of planet formation in the atmospheres of hot Jupiters

ABSTRACT The atmospheric chemical composition of a hot Jupiter can lead to insights into where in its natal protoplanetary disc it formed and its subsequent migration pathway. We use a 1D chemical kinetics code to compute a suite of models across a range of elemental abundances to investigate the resultant abundances of key molecules in hot Jupiter atmospheres. Our parameter sweep spans metallicities between 0.1x and 10x solar values for the C/H, O/H, and N/H ratios, and equilibrium temperatures of 1000 and 2000 K. We link this parameter sweep to the formation and migration models from previous works to predict connections between the atmospheric molecular abundances and formation pathways, for the molecules H2O, CO, CH4, CO2, HCN, and NH3. We investigate atmospheric H2O abundances in eight hot Jupiters reported in the literature. All eight planets fall within our predicted ranges for various formation models; however, six of them are degenerate between multiple models and hence require additional molecular detections for constraining their formation histories. The other two planets, HD 189733 b and HD 209458 b, have water abundances that fall within ranges expected from planets that formed beyond the CO2 snowline. Finally, we investigate the detections of H2O, CO, CH4, CO2, HCN, and NH3 in the atmosphere of HD 209458 b and find that, within the framework of our model, the abundances of these molecules best match with a planet that formed between the CO2 and CO snowlines and then underwent disc-free migration to reach its current location.

A Simple and Real-Time Support System for Firefighters Using Low-Cost 3-DOF Accelerometer and CO Sensor

During the operations, firefighters can be injured or killed because of the smoke and heat emission from the fire area, broken structure elements such as floors, walls, or boiling liquid ejection and gas explosion. Therefore, this paper aims to develop an efficient and portable system to monitor falls and high CO level through integrating a three degrees of freedom accelerometer and an MQ7 sensor to recorded acceleration and measured CO concentration with the embedded fall and high CO detection algorithms. The embedded fall detection algorithm can detect fall events with ultra-high accuracy without mistakenly identifying normal activities such as walking, standing, jogging, and jumping as fall events. The posture recognition and cascade posture recognition after three seconds are proposed in this paper to gain the accuracy of our proposed fall detection system. If a firefighter falls and is unable to stand up, the alert signal message will be sent to their commander outside through the GSM/GPRS module. The embedded high CO detection algorithm used to alert the dangerous CO level to recommend using self-contained breathing apparatuses (SCBA) and saving fresh air with acceptable CO level. We carefully investigated the proposed thresholds and window size before embedding them into the microcontroller. The sensitivity and accuracy achieved were around 96.5% and 93% respectively in our recorded data. Furthermore, the proposed fall detection algorithm also achieved higher geometric mean in comparison with Support Vector Machine classifier (SVM) and a nearest neighbor rule (NN) in the public datasets with the achieved around 99.44%, 98.41% and 95.76% respectively.

First-principles predictions of tunable half metallicity in zigzag GaN nanoribbons with possible applications in CO detection and spintronics

Based on systematic first-principles density-functional theory simulations, we predict that the zigzag GaN nanoribbons (ZGaNNRs) can be used both as highly efficient CO detectors as well as spin filters. Our calculations, performed both on infinitely long nanoribbons, and also on finite strands, suggest that: (a) CO binds strongly at the edges of ZGaNNRs, and (b) that several of the resultant configurations exhibit half-metallic behavior. We considered various edge-passivation sites and found that all the resultant structures are thermodynamically stable. The metallic, half-metallic, and semiconducting configurations are observed as a function of CO passivation coverage. We also compute the current–voltage (I–V) characteristics of various structures using the Landauer formalism, and find that the devices made up of half-metallic configurations act as highly-efficient spin filters. The effect of CO concentration is also investigated which suggests a viable way to not just tune the electronic band gap of ZGaNNRs, but also their half metallicity. Our simulations thus suggest a new direction of research for possible device applications of III–V heterostructures.

Dissolved Gas Analysis in Transformer Oil Using Ni Catalyst Decorated PtSe2 Monolayer: A DFT Study

In this paper, the first-principles theory is used to explore the adsorption behavior of Ni catalyst decorated PtSe2 (Ni-PtSe2) monolayer toward the dissolved gas in transformer oil, namely CO and C2H2. Some Ni atoms from the catalyst are trapped in the Se vacancy on the pure PtSe2 surface. The geometry configurations of Ni-PtSe2 monolayer before and after gas adsorption, the electronic property of Ni-PtSe2 monolayer upon gas adsorption, and the sensibility and recovery property of Ni-PtSe2 monolayer are explored in this theoretical work. Through the simulation, the Ead of CO and C2H2 gas adsorption systems are calculated as −1.583 eV and −1.319 eV, respectively, both identified as chemisorption and implying the stronger performance of the Ni-PtSe2 monolayer on CO molecule, which is further supported by the DOS and BS analysis. According to the formula, the sensitivity of Ni-PtSe2 monolayer towards CO and C2H2 detection can reach up to 96.74% and 99.91% at room temperature (298 K), respectively, which manifests the favorable sensing property of these gases as a chemical resistance-type sensor. Recovery behavior indicates that the Ni-PtSe2 monolayer is a satisfied gas scavenger upon the noxious gas dissolved in transformer oil, but its recovery time at room temperature is not satisfactory. To sum up, we monitor the status of the transformer to guarantee the stable operation of the power system through the Ni-PtSe2 monolayer upon the detection of CO and C2H2, which may realize related applications, and provide the basis and reference to cutting-edge research in the field of electricity in the future.

CO2-ZrO2 interaction in CDRM: A combined experimental and theoretical study

Stable CDRM performance of a catalyst is dominantly determined by its ability to dissociate CO2 to produce and utilize surface oxygen at rates high enough to clean surface carbon formed on its active sites. The current study is an attempt to understand the nature of CO2 activation on a commercial ZrO2, which is a widely used CDRM support responsible for CO2 dissociation and surface O mobility, via combined evaluation of computational and experimental findings. Accordingly, significant ZrO2-CO2 interaction, which is affected by temperature, was confirmed via FTIR-DRIFTS through surface bicarbonate, carbonate, formate and OH species as well as bridged CO detection. Though DFT calculations on periodic models revealed that upon CO2 adsorption at the possible active sites on stoichiometric m-ZrO2(1¯11) bidentate and tridentate carbonates were formed, a dissociative CO2 adsorption did not take place on the surface. Results of the DFT simulations performed on O–ZrO2 system has shown that m-ZrO2 surface enables oxygen mobility. Based on the results, CO2 dissociation on ZrO2 is proposed to occur on oxygen vacancy and defect sites verified by XPS analysis and/or via reversible formate formation/decomposition mechanism.

The Trace Gas Monitoring Method Based on Diode Laser Wavelength-Modulation Spectroscopy Technology for the Detection of Clinical Blood Infection

It is important to monitor and evaluate the growth of microorganisms in order to accurately judge the situation of blood microbial infection. In this paper, diode laser wavelength modulation spectroscopy (DLWMS) technology is used to design a set of low-cost, high sensitivity, fast dynamic responses and a non-invasive trace gas measurement system, which can quickly and accurately assess the concentration of carbon dioxide (CO2) produced by blood microbial reproduction. The measurement principle and spectral processing algorithm of DLWMS are introduced first. The automatic and rapid detection of CO2 is realized through a self-designed optical system. By using the system to detect blood infection, the accuracy of the technology was verified. Therefore, it also indicates that DLWMS CO2 monitoring is a highly sensitive, fast-response and non-invasive technology, which can accurately and quickly determine blood infection and meet the clinical application requirements of human septicemia, bacteremia and other diseases.

Adsorption and sensing performances of Rh-embedded PtSe2 monolayer upon CO and HCHO in dry-type reactors: A first-principles study

Based on the first-principles method, we theoretically analyze the Rh-embedded PtSe2 (Rh-PtSe2) monolayer as a potential gas sensor in this paper, for detection of CO and HCHO in the dry-type reactor to evaluate its operation status. The Rh-embedding behavior is performed by substituting a Se atom at the topmost Se layer of the pristine PtSe2 monolayer, and we find that the Rh atom can be stably and energy-favorably embedded in the PtSe2 monolayer with the formation energy (Eform) of −0.53 eV. Chemisorption is identified for the CO and HCHO system, with the adsorption energy (Ead) as −1.89 and −1.05 eV, respectively. The electronic property analysis reveals that the Rh-PtSe2 monolayer can be a promising resistance-type sensor or a field-effect transistor sensor for detection of two gas species, with good sensing response or selectivity. This theoretical work can pave the way to further investigate the sensing application of Rh-PtSe2 monolayer upon toxic gases in the dry-type reactors, and related experimental research can verify our findings and to confirm that Rh-PtSe2 monolayer is a promising sensing candidate to evaluate the operation status of the dry-type reactors in the power system.

Simultaneous detection of atmospheric CO2 and H2O using a DFB diode laser based absorption spectrometer

In this paper, a high-resolution absorption spectrometer based on a continuous wave (CW) distributed feedback (DFB) diode laser near 2682.8 nm spectral region is developed, which is suitable for high sensitive detection of trace CO2 and H2O simultaneously. Spectral parameters (line strengths, air- and self-broadening coefficients) for CO2 absorption line at 3727.08279 cm−1 and H2O absorption line at 3727.73765 cm−1 are experimentally investigated, and a good agreement was obtained by comparing with the HITRAN database. H2O induced CO2 broadening coefficient is especially measured to upgrade the spectral signal processing algorithm model for field application. Finally, the developed diode laser absorption spectrometer was continuously deployed at AECORSQ Observatory onMt. Qomolangma, China, for approximate two days, which demonstrated the high sensitivity and stability of the sensor system for continuously atmospheric CO2 and H2O background observation.

Real-Time Monitoring of Gas-Phase and Dissolved CO2 Using a Mixed-Matrix Composite Integrated Fiber Optic Sensor for Carbon Storage Application.

Novel chemical sensors that improve detection and quantification of CO2 are critical to ensuring safe and cost-effective monitoring of carbon storage sites. Fiber optic (FO)-based chemical sensor systems are promising field-deployable systems for real-time monitoring of CO2 in geological formations for long-range distributed sensing. In this work, a mixed-matrix composite integrated FO sensor system was developed with a purely optical readout that reliably operates as a detector for gas-phase and dissolved CO2. A mixed-matrix composite sensor coating consisting of plasmonic nanocrystals and hydrophobic zeolite embedded in a polymer matrix was integrated on the FO sensor. The mixed-matrix composite FO sensor showed excellent reversibility/stability in a high humidity environment and sensitivity to gas-phase CO2 over a large concentration range. This remarkable sensing performance was enabled by using plasmonic nanocrystals to significantly enhance the sensitivity and a hydrophobic zeolite to effectively mitigate interference from water vapor. The sensor exhibited the ability to sense CO2 in the presence of other geologically relevant gases, which is of importance for applications in geological formations. A prototype FO sensor configuration, which possesses a robust sensing capability for monitoring dissolved CO2 in natural water, was demonstrated. Reproducibility was confirmed over many cycles, both in a laboratory setting and in the field. More importantly, we demonstrated on-line monitoring capabilities with a wireless telemetry system, which transferred the data from the field to a website. The combination of outstanding CO2 sensing properties and facile coating processability makes this mixed-matrix composite FO sensor a good candidate for practical carbon storage applications.

Semiconductor-Type Gas Sensors Based on γ-Fe2O3 Nanoparticles and Its Derivatives in Conjunction with SnO2 and Graphene

The gas sensitivity of semiconductor metal oxides, such as γ-Fe2O3 and SnO2, is investigated together with the synergistic effects in conjunction with grapheme. Nanoparticles of γ-Fe2O3, γ-Fe2O3/SnO2, and γ-Fe2O3/SnO2/RGO, prepared by two-step fabrication, were assembled in gas-sensing devices to assess their sensitivities; response and recovery times for the detection of ethanol, methanol, isopropanol, formaldehyde, H2S, CO, and NO gases at different temperatures but constant concentrations of 100 particles per million (ppm); and H2S, which underwent the dynamic gas sensitivity test in different concentrations. Each sample’s crystallinity and microscopic morphology was investigated with X-ray diffraction and a scanning electron microscope. In comparative gas sensitivity measurements, the ternary composite of γ-Fe2O3/SnO2/RGO was identified as an ideal candidate, as it responds to all four tested liquids in the gas phase as well as H2S with a response value equal to 162.6. Further, only the ternary composite γ-Fe2O3/SnO2/RGO hybrid nanoparticles responded to NO gas with a sensor response value equal to 4.09 in 12 s. However, only the binary composite γ-Fe2O3/SnO2 responded to CO with a corresponding sensitivity of 1.59 units in 7 s.

Photothermal multi-species detection in a hollow-core fiber with frequency-division multiplexing

A photothermal gas sensor has been developed for simultaneous multi-species detection in a hollow-core fiber based on the frequency-division multiplexing technique. By passing multiple pump lasers and a probe laser through a gas-filled hollow-core anti-resonant fiber (HC-ARF), the absorption-generated modulation of the refractive index at various frequencies is sensitively detected by an in-line interferometer. Three distributed-feedback diode lasers at C-band, L-band and U-band are employed as pump lasers for C2H2, CO2 and CH4 detection. Assisted by optical power amplifiers, the sensor achieves noise equivalent concentrations of 2.5 ppb, 21 ppm and 200 ppb for C2H2, CO2 and CH4, respectively. The sensor demonstrates excellent linear response to gas concentrations with R-square values between 0.996 and 0.999. Measurement of the three gas species with time-varying concentrations, as well as the aforementioned experiments, further validates the simultaneous multi-species detection with high sensitivity, compact size, and extremely low gas consumption.

Jansky Very Large Array Detections of CO(1–0) Emission in H i-absorption-selected Galaxies at z ≳ 2

We report a Karl G. Jansky Very Large Array search for redshifted CO(1–0) emission from three H i-absorption-selected galaxies at z ≈ 2, identified earlier in their CO(3–2) or CO(4–3) emission. We detect CO(1–0) emission from DLA B1228-113 at z ≈ 2.1933 and DLA J0918+1636 at z ≈ 2.5848; these are the first detections of CO(1–0) emission in high-z H i-selected galaxies. We obtain high molecular gas masses, M mol ≈ 1011 × (α CO/4.36) M ⊙, for the two objects with CO(1–0) detections, which are a factor of ≈1.5–2 lower than earlier estimates. We determine the excitation of the mid-J CO rotational levels relative to the J = 1 level, r J1, in H i-selected galaxies for the first time, obtaining r 31 = 1.00 ± 0.20 and r 41 = 1.03 ± 0.23 for DLA J0918+1636, and r 31 = 0.86 ± 0.21 for DLA B1228-113. These values are consistent with thermal excitation of the J = 3 and J = 4 levels. The excitation of the J = 3 level in the H i-selected galaxies is similar to that seen in massive main-sequence and submillimeter galaxies at z≳2, but higher than that in main-sequence galaxies at z ≈ 1.5; the higher excitation of the galaxies at z ≳ 2 is likely to be due to their higher star formation rate (SFR) surface density. We use Hubble Space Telescope Wide Field Camera 3 imaging to detect the rest-frame near-ultraviolet (NUV) emission of DLA B1228-113, obtaining an NUV SFR of 4.44 ± 0.47 M ⊙ yr−1, significantly lower than that obtained from the total infrared luminosity, indicating significant dust extinction in the z ≈ 2.1933 galaxy.

A Massive, Dusty, Hi Absorption–Selected Galaxy at z ≈ 2.46 Identified in a CO Emission Survey

We report a NOrthern Extended Millimeter Array (NOEMA) and Atacama Large Millimeter/submillimeter Array search for redshifted CO emission from the galaxies associated with seven high-metallicity ([M/H] ≥ −1.03) damped Lyα absorbers (DLAs) at z ≈ 1.64–2.51. Our observations yielded one new detection of CO(3–2) emission from a galaxy at z = 2.4604 using NOEMA, associated with the z = 2.4628 DLA toward QSO B0201+365. Including previous searches, our search results in detection rates of CO emission of % and %, respectively, in the fields of DLAs with [M/H] > −0.3 and [M/H] < −0.3. Further, the Hi–selected galaxies associated with five DLAs with [M/H] > −0.3 all have high molecular gas masses, ≳5 × 1010 M ⊙. This indicates that the highest-metallicity DLAs at z ≈ 2 are associated with the most massive galaxies. The newly identified z ≈ 2.4604 Hi–selected galaxy, DLA0201+365g, has an impact parameter of ≈7 kpc to the QSO sightline, and an implied molecular gas mass of (5.04 ± 0.78) × 1010 × (α CO/4.36) × (r 31/0.55) M ⊙. Archival Hubble Space Telescope Wide Field and Planetary Camera 2 imaging covering the rest-frame near-ultraviolet (NUV) and far-ultraviolet (FUV) emission from this galaxy yield nondetections of rest-frame NUV and FUV emission, and a 5σ upper limit of 2.3 M ⊙ yr−1 on the unobscured star formation rate (SFR). The low NUV-based SFR estimate, despite the very high molecular gas mass, indicates that DLA0201+365g either is a very dusty galaxy, or has a molecular gas depletion time that is around 2 orders of magnitude larger than that of star-forming galaxies at similar redshifts.

Probing Cold Gas in a Massive, Compact Star-forming Galaxy at z = 6

Observations of low-order 12C16O transitions represent the most direct way to study galaxies’ cold molecular gas, the fuel of star formation. Here we present the first detection of CO(J = 2 → 1) in a galaxy lying on the main-sequence of star-forming galaxies at z > 6. Our target, G09-83808 at z = 6.03, has a short depletion timescale of τ dep ≈ 50 Myr and a relatively low gas fraction of M gas/M ⋆ ≈ 0.30 that contrasts with those measured for lower-redshift main-sequence galaxies. We conclude that this galaxy is undergoing a starburst episode with a high star formation efficiency that might be the result of gas compression within its compact rotating disk. Its starburst-like nature is further supported by its high star formation rate surface density, thus favoring the use of the Kennicutt–Schmidt relation as a more precise diagnostic diagram. Without further significant gas accretion, this galaxy would become a compact, massive quiescent galaxy at z ∼ 5.5. In addition, we find that the calibration for estimating interstellar medium masses from dust continuum emission satisfactorily reproduces the gas mass derived from the CO(2 → 1) transition (within a factor of ∼2). This is in line with previous studies claiming a small redshift evolution in the gas-to-dust ratio of massive, metal-rich galaxies. In the absence of gravitational amplification, this detection would have required of order 1000 hr of observing time. The detection of cold molecular gas in unlensed star-forming galaxies at high redshifts is thus prohibitive with current facilities and requires a tenfold improvement in sensitivity, such as that envisaged for the Next-Generation Very Large Array .

First-principles probing of Au-doped WS2 monolayer as a superb CO sensor with high selectivity and fast diffusion

Doping with noble metals is considered to be an effective strategy to improve the gas sensitivity of 2D WS2 materials. In this work, the adsorption properties of CO, CO2, NH3 and SO2 on both pure and Au-doped WS2 monolayers are investigated in detail by first-principles calculations. The results show that the adsorption energy of CO on the WS2 monolayer doped with an Au atom is significantly lower than that of the pure WS2 monolayer (−0.15 eV reduced to −0.35 eV). From analysis of the adsorption configuration, it can be found that the CO molecule and WS2/Au monolayer form a new C = S double bond with a bond length of 2.067 Å due to chemisorption, and the calculated results of charge density difference (CDD) and electron localization function (ELF) also show that there exists the charge transfer and electron co-existence occur between them. Further, the density of states (DOS) of the WS2/Au monolayer shifts towards the lower energy state after adsorbing the CO molecule, indicating excellent CO detection sensitivity. On the other hand, both before and after doping with an Au atom, the WS2 monolayer always exhibits weak physical adsorption and insignificant changes in electronic properties for CO2, NH3 and SO2 molecules. Finally, the calculated diffusion coefficients indicate that the CO molecules diffuse more easily on the surface of the WS2/Au monolayer than the other three gases. These findings provide a theoretical basis for the Au-doped WS2 monolayer to improve the detection performance for CO.

High-throughput detection of metal contamination in HTS outputs.

Large compound libraries utilised for HTS often include metal contaminated compounds which can interfere with assay signal or target biology, and therefore appear as hits. Pursuit of these compounds can divert considerable time and resource away from more propitious hits, yet there is currently no established method of detecting metal impurities in a rapid and effective manner. Here we describe the development and application of a high-throughput method to identify metal contaminants using acoustic mist ionisation mass spectrometry (AMI-MS). Although metals species by themselves are not detectable by AMI-MS, we have identified two compounds that chelate metal ions and enable their detection. 6-(diethylamino)-1,3,5-triazine-2,4(1H,3H)-dithione (DMT) and 1-(3-{[4-(4-cyanophenyl)-1-piperidinyl]carbonyl}-4-methylphenyl)-3-ethylthiourea (TU) can form complexes with a range of metal ions. Using a collection of metal catalysts, we have developed two metal chelator assays that collectively allow for the detection of Ag, Au, Co, Cu, Fe, Pd, Pt and Zn. We employed these assays to profile the hit outputs of a Zn liable target, and a Pd liable target, and identified significant quantities of metal contaminated compounds in the HTS outputs. This work provides a method of rapidly identifying metal impurities in hit compounds and has become part of an established workflow in triaging HTS outputs at AstraZeneca, facilitating faster identification of robust lead series.

Colorimetric Detection of Fe(II) and Co(II) by Using Terpyridine-Based Derivative

Colorimetric Detection of Fe(II) and Co(II) by Using Terpyridine-Based Derivative

Co2+ and nitrobenzene sensing using indium-based metal-organic framework

A highly stable indium-based metal-organic framework, namely [In(HTCA)(OH)]·2DMF·H2O (JOU-24), was solvothermally synthesized by using fluorescent ligand H3TCA (H3TCA = 4,4′,4″-tricarboxytriphenylamine). Single-crystal X-ray diffraction analyses show that JOU-24 displays two-dimensional framework based on infinite straight In-O-In chains. Further studies show that JOU-24 can keep its stability in water with pH range from 1 to 11. Thereafter, JOU-24 was developed as an excellent fluorescence sensor for selective detection of Co2+ and nitrobenzene (NB) in water due to its good fluorescence performance. For Co2+ sensing, a high quenching content is determined to be 24,500 with a low determine limit of 4.9 × 10−6 mol/L. For NB sensing, quenching content is 10230, which is also comparable to other reported MOFs. In addition, the mechanism for Co2+ and NB sensing is also proposed. This work shows a simple method to construct high-efficient fluorescence sensor for metal ions and nitroaromatics detection.