Gas Adsorption-desorption Research Articles

Fractal Strategy for Improving Characterization of N2 Adsorption–Desorption in Mesopores

The current studies primarily analyze the heterogeneity and complexity of mesopore structures based on low-temperature nitrogen (N2) adsorption curves and the Frenkel–Halsey–Hill (FHH) fractal model. However, these studies ignore the fact that the low-temperature N2 desorption curve can also reflect the desorption performance of the mesopore structure. In this research, novel fractal indicators for characterizing the adsorption–desorption performance of mesopores based on the fractal dimension from the N2 adsorption curves and N2 desorption curves are proposed. The novel fractal indicators I1 and I2 are applied to evaluate the adsorption–desorption performance of mesopores with pore size 2–5 nm and pore size 5–50 nm, respectively. The fractal indicator I1 shows an increasing trend with coalification, reflecting that the gas adsorption performance of 2–5 nm mesopores is enhanced with coalification. The fractal indicator I2 exhibits a trend of first increasing and then decreasing with coalification, indicating the gas desorption performance of mesopores with pore size 5–50 nm decreases first and then increases. The proposed indicators provide novel analytical parameters for further understanding the gas adsorption–desorption mechanism of porous coal-based or carbon-based materials.

An improved two-phase rate transient analysis method for multiple communicating multi-fractured horizontal wells in shale gas reservoirs: Field cases study

The reduction in well spacing for multi-fractured horizontal wells (MFHWs) and the increase in infill drilling exacerbate the risk of fracture communication. This presents substantial challenges for the rate transient analysis of the parent–child well system. This study proposes an improved two-phase straight-line analysis method to evaluate the linear flow parameters of multiple communicating MFHWs in shale gas reservoirs. Considering shale gas adsorption–desorption mechanisms, nonuniform length of fractures, stress-dependent effects, and matrix shrinkage effects, two-phase productivity equation is established within the dynamic drainage area (DDA). Subsequently, we develop a three-well square root of time plot based on DDA correction and propose a rigorous workflow for evaluating linear flow parameters in single-well, two-well, and three-well systems. The straight lines on the parent well's square root of the time plot exhibit varying degrees of jumps, depending on the frequency of fracture communication. After communication, it is necessary to adjust the cumulative production and production time of the parent well to accurately recalculate the average pressure within the drainage area. Numerical simulations are employed to generate a series of cases under different reservoir conditions to validate the accuracy of the proposed model. The results show that the model estimates fracture half-lengths with errors within 8%, meeting the precision requirements for field applications. Additionally, the method exceeds numerical simulations in computational speed. Two field case studies in the WY Basin, China, further illustrate the effectiveness and practicality of the proposed method, providing theoretical support for hydraulic fracturing construction design and development planning.

Hydrogen and Cushion Gas Adsorption-Desorption Dynamics on Clay Minerals.

Transitioning toward a hydrogen (H2)-centric energy paradigm necessitates understanding the adsorption properties of clay minerals, essential constituents of reservoirs and caprocks, for efficient geological H2 storage. This study examines the adsorption characteristics of H2 on various clay minerals (montmorillonite, illite, chlorite, kaolinite, and sepiolite) at different temperatures and the adsorption of cushion gases (N2, CH4, and CO2) under reservoir conditions (313.15 K, up to 10 MPa). The results indicate that sepiolite demonstrates superior adsorption capacity under all tested conditions, surpassing montmorillonite by over 12 times at 313.15 K for H2. Illite, chlorite, and kaolinite exhibit negligible H2 adsorption. Thermodynamic analysis reveals that H2 adsorption on clay minerals is a nonspontaneous and exothermic physisorption process. H2 loss due to adsorption hysteresis in montmorillonite and sepiolite is 42.19 and 3.56%, respectively. Sepiolite may exhibit more predictable and stable sorption properties under repeated pressure variations. The H2 adsorption capacity of montmorillonite and sepiolite is merely 0.4 and 4.5% of that of CO2, respectively. This study provides valuable insights for selecting clay minerals and cushion gases for efficient geological H2 storage and natural hydrogen exploration.

Deformation-induced gas adsorption and self-desorption dynamics of a carbon nano-network: Molecular dynamics modeling focusing on CO2 capture

Gas adsorption and separation/desorption are two pivotal stages in gas capture, demanding additional energy for liberating gas molecules from the adsorbent. Hence, it’s essential to engineer an adsorbent with minimal energy consumption yet effective gas adsorption–desorption characteristics. Accordingly, this research introduces a carbon nano-network (CNN) material capable of inhaling and exhaling gases via self-deformation. Molecular dynamics simulations demonstrate that the gas adsorption–desorption capabilities of CNN can be efficiently regulated by its deformation. While the size of CNN minimally affects the gas sorption rate, a larger CNN necessitates a prolonged duration to achieve saturation under identical gas conditions. Incorporating elongated appendages in CNN enhances both its stability during contraction and its efficiencies in gas adsorption and desorption. We discerned that attaining a critical gas density within a confined space is imperative to initiate self-desorption of CNN. Specifically, if the gas density dips below this critical threshold–set at 5.2 times that of CO2 at room temperature (300 K) and atmospheric pressure (1 Bar)–CNN exhibits no self-desorption capability. Nevertheless, even a marginal elevation in gas density triggers and maintains self-desorption with a consistently surpassing desorption ratio of 98 %. This discovery offers valuable insights for designing automatic self-desorption materials or apparatuses.

Introducing a novel Hierarchy-Connectivity factor for characterizing micro-mesoporous materials

To provide a comprehensive description of hierarchical pore networks and optimize micro-mesoporous materials, it is essential to consider pore connectivity as a parameter. This study introduces an innovative hierarchy-connectivity factor (HCF) that includes the volume, size, and connectivity data of pores within the pore network. This study covers micro-mesoporous biosourced carbons, with ordered or disordered mesoporous structures, and three commercial activated carbons derived from petroleum coke and biomass. A dual-shape slit-cylinder model was employed to precisely assess the textural properties of these carbons. The proposed methodology evaluates connectivity exclusively through gas adsorption–desorption isotherm analysis, providing a rapid and practical tool for characterizing the porous network of carbon materials. The efficacy of this HCF is demonstrated in the examination of carbon materials functioning as electrodes for supercapacitors. Overall, this research transcends the field of gas adsorption-based studies, highlighting the importance of evaluating the pore network connectivity within carbon materials in order to optimize them for a particular application. Importantly, this contribution could be extended beyond the scope of carbon materials, encompassing a broader spectrum of porous materials.

Fabrication of Nanocellulose/Chitosan Nanocomposite Based on Loofah Sponge for Efficient Removal of Methylene Blue: Thermodynamic and Kinetic Investigations

AbstractWe established three nano-solid adsorbents: nanocellulose based on plant loofah sponge (NC), chitosan (CS), and nanocellulose/chitosan composite (CSC). These substances were employed as solid adsorbents to eliminate methylene blue (MB) dye from wastewater. Various characterization techniques were employed to investigate all the synthesized solid adsorbents, including TGA (thermogravimetric analysis), XRD (X-ray diffraction spectra), (BET) nitrogen gas adsorption-desorption, SEM (scanning electron microscope), TEM (transmission electron microscopy), FTIR (Fourier transform infrared) spectrometer, and zeta potential. According to our results, CSC showed greater thermal stability than LS and NC but lower than CS, mesoporous (2.012 nm), higher total pore volume (0.366 cm3. g− 1), specific surface area (639.3 m2. g− 1), and pHpzc of 7.22. The static adsorption of MB was well described by the Langmuir (R2 > 0.9872), Temkin (R2 > 0.9668), and Dubinin-Radushkevich (R2 > 0.9485) models. The composite of nanocellulose and chitosan exhibited the highest Langmuir adsorption capacity (301.20 mg. g− 1) at 47 °C after a 24 h shaking period at a dosage of 2 g. L− 1 as the adsorbent and pH of 7. The adsorption of MB by the fabricated solid materials fitted well with the linear PSO (R2 > 0.9806) and Elovich (R2 > 0.9574) kinetic model. The enthalpy, entropy, and free energy change for the adsorption of MB onto CSC were determined to be 47.11 kJ. mol− 1, 0.172 kJ. mol− 1. K− 1, and − 3.29 kJ. mol− 1, respectively at 20 °C. Thermodynamic investigation showed that MB adsorption is spontaneous, endothermic, favorable (0 < RL<1, 0.017–0.313), and physisorption (EDR < 8 kJ. mol− 1). Compared to the other eluents, nitric acid produced the highest desorption percentage (98.5%).

Understanding the origins of reversible and hysteretic pathways of adsorption phase transitions in metal-organic frameworks

Phase behavior of nanoconfined fluids adsorbed in metal–organic frameworks is of paramount importance for the design of advanced materials for energy and gas storage, separations, electrochemical devices, sensors, and drug delivery, as well as for the pore structure characterization. Phase transformations in adsorbed fluids often involve long-lasting metastable states and hysteresis that has been well-documented in gas adsorption–desorption and nonwetting fluid intrusion-extrusion experiments. However, theoretical prediction of the observed nanophase behavior remains a challenging problem. The mesoscopic canonical, or mesocanonical, ensemble (MCE) is devised to study the nanophase behavior under conditions of controlled fluctuations to stabilize metastable and labile states. Here, we implement and apply the MCE Monte Carlo (MCEMC) simulation scheme to predict the origins of reversible and hysteric adsorption phase transitions in a series of practical MOF materials, including IRMOF-1, ZIF-412, UiO-66, Cu-BTC, IRMOF-74-V, VII, and IX. The MCEMC method, called the gauge cell method, allows to produce Van der Waals type isotherms with distinctive swings around the phase transition regions. The constructed isotherms determine the positions of phase equilibrium and spinodals, as well as the nucleation barriers separating metastable states. We demonstrate the unique capabilities of the MCEMC method in quantitative predictions of experimental observations compared with the conventional grand canonical and canonical ensemble simulations. The MCEMC method is implemented in the open-source RASPA and LAMMPS software packages and recommended for studies of adsorption behavior and pore structure characterization of MOFs and other nanoporous materials.

Characteristics of the gas diffusion in water-bearing coal with different damage degree and its influence mechanism

The moisture content and degree of damage in water-bearing coal affect the gas diffusion characteristics in coal, which limits the effect of gas extraction. The experiments were carried out on water-bearing coal with different damage degrees using a self-built coal and gas adsorption–desorption system to study the gas diffusion characteristics of water-bearing coal with varying degrees of damage. The results show that the pore volume of tectonic coal is positively correlated with the degree of damage. The increased moisture content in coal decreases gas desorption performance, embodied in the simultaneous reduction of desorption amount, desorption speed, and diffusion coefficient. Under the same water content condition, the gas desorption amount, gas desorption rate, and gas diffusion coefficient of coal with different damage degrees all show a downward trend, and the decline range is positively correlated with the water content. The relation between the amount of gas desorption, the time, and the moisture content of the water-bearing coal with different damage degrees has been set up. The study results provide a solid theoretical foundation for evaluating and predicting the gas extraction characteristics of coal seams with varying degrees of damage.

A field study of pore-network systems on the tight shale gas formation through adsorption-desorption technique and mercury intrusion capillary porosimeter: Percolation theory and simulations

Properly identifying microscopic pore structure properties of shale reservoirs is essential for developing efficient extraction techniques of shale hydrocarbons. To understand the unique and complex pore network of the Northern Guizhou shale reservoir, shale samples from the Wufeng-longmaxi Formation were investigated using different analytical techniques, X-Ray Diffractometry, low-pressure nitrogen gas adsorption-desorption isotherms, and Mercury intrusion capillary porosimeter. Results indicate that the Wufeng-longmaxi formation is mainly composed of a high quantity of quartz ranging from 0.6 % to 64.1 % and an average extent of 55.825 %, the lowest amount of potassium feldspar ranging from 0.6 % to 2.2 % and an average extent of 1.45 % with Total organic contents ranging from 3.672 to 5.209 %. Similarly, the BJH adsorption techniques for pore volume and area were investigated. The results indicate the dominance of the mesopore with pore size ranging from 2.03 nm to 40nm, average pore volume of 0.073715 m3/g, and average pore area of 13.0324 m2/g. The pore throat distributions from MICP showed drain pressure and median pore throat radius ranging from 0.47 to 13.79 MPa and 0.05–0.08 μm, respectively. Suggested complementary experimental techniques reveal the connectivity of pore networks of the Wufeng-longmaxi Formation shale reservoir, which shows a high production potential of hydrocarbons. The findings of this study can provide a valuable understanding of fluid transport properties and storage space of shale gas that can help decision-makers as they set exploration initiatives for shale gas reservoirs.

Micropatternable Ink Composed of MAX Phase ZIF-8 for Gas Sensing Applications

This work provides a detailed introduction to the preparation methods, structural characteristics, and various performance tests of the Ti3C2/ZIF-8 composite material. Initially, the composite material is obtained through the synthesis, mixing, and subsequent processing of MXene solution and ZIF-8 nanoparticles. The coating structure and properties were comprehensively characterized using SEM, TEM, and XRD. These analyses revealed the material's layered structure, high crystallinity, and surface activity. BET analysis of Ti3C2/ZIF-8 also shows excellent gas adsorption-desorption performance, having an especially high-efficiency adsorption capacity for VOCs. TGA further demonstrates the thermal stability and chemical stability of Ti3C2/ZIF-8 and its printability was tested indicating widespread application potential in coating preparation through ultrasonic spray technology. Finally, we show methods to regulate and control coating thickness and roughness for precision manufacturing. These analyses together emphasize the application value of Ti3C2/ZIF-8 in fields such as gas-storage, gas-separation, and environmental monitoring.

Adsorption–desorption characteristics of coal-bearing shale gas under three-dimensional stress state studied by low field nuclear magnetic resonance spectrum experiments

The micro-scale gas adsorption–desorption characteristics determine the macro-scale gas transport and production behavior. To reveal the three-dimensional stress state-induced gas adsorption–desorption characteristics in coal-bearing shale reservoirs from a micro-scale perspective, the coal-bearing shale samples from the Dongbaowei Coal Mine in the Shuangyashan Basin were chosen as the research subject. Isothermal adsorption–desorption experiments under three-dimensional stress state were conducted using the low field nuclear magnetic resonance (L-NMR) T2 spectrum method to simulate the in-situ coal-bearing shale gas adsorption–desorption process. The average effective stress was used as the equivalent stress indicator for coal-bearing shale, and the integral of nuclear magnetic resonance T2 spectrum amplitude was employed as the gas characterization indicator for coal-bearing shale. A quantitative analysis was performed to examine the relationship between gas adsorption in coal-bearing shale and the average effective stress. And a quantitative analysis was performed to examine the relationship between the macroscopic and microscopic gas quantities of coal-bearing shale. Experimental findings: (1) The adsorption–desorption process of coal-bearing shale gas follows the L-F function model and the D-A-d function model respectively with respect to the amount of gas and the average effective stress. (2) There is a logarithmic relationship between the macroscopic and microscopic gas quantities of coal-bearing shale during the adsorption–desorption process. This quantitatively characterizes the differences in the curves, which may be related to the elastic–plastic deformation, damage and fracture of the micropores in coal-bearing shale, as well as the hysteresis of gas desorption and the stress field of the gas occurrence state.

A comparative DFT study on the adsorption properties of lithium batteries thermal runaway gases CO, CO2, CH4 and C2H4 on pristine and Au doped CdS monolayer

The thermal runaway gases, such as CO, CO2, CH4, and C2H4, will leak from the battery electrolyte when lithium batteries in extreme discharge or thermal runaway conditions. The structural properties, differential charge density (DCD), density of state (DOS), gas adsorption properties, desorption time, work function and front-orbit theory calculation of pristine and Au doped CdS monolayer are explored and compared by first-principle calculation. The adsorption energy of CO, CO2, CH4 and C2H4 on the surface of Au–CdS are –0.89 eV, –0.40 eV, –0.14 eV and –0.77 eV, respectively. After doping, the adsorption type of CO and C2H4 are chemical type. Partial density of states shows that the gas molecules react with doped precious metal atoms. The adsorption ability of Au–CdS can be ranged as CO>C2H4>CO2>CH4. C2H4 on the surface of Au–CdS can desorb within 10 s at room temperature. As a result, Au–CdS exhibits tremendous prospective application as CO or C2H4 gas sensor. This study demonstrates that the adsorption and sensing properties of CdS monolayer can be improved effectively by the introduction of precious metal.

Linear enhancement of mechanical compliance by zeolite filling in a compact loudspeaker

A zeolite filling in the rear cavity of a compact loudspeaker enhances the sound pressure amplitude of the loudspeaker system with a frequency range up to ∼500 Hz, but its intrinsic mechanisms remain elusive. We theoretically consider the gas adsorption–desorption behavior on zeolite that can be dynamically perturbed by sound pressure from the diaphragm of the loudspeaker. By merging equivalent circuit theory with gas thermodynamic theory, a linear relationship between mechanical compliance and zeolite volume in the rear cavity is quantitatively modeled. Confirmed by electroacoustic impedance experiments, the linear relationship with a slope of 1.92 mF cm−3 reveals the intrinsic ability of porous material to enhance mechanical compliance by adsorption of gas onto the zeolite in the rear cavity. This study correlates the kinetic behavior of air molecules on zeolite and acoustic behavior; it offers a novel insight to improve the performance of a compact loudspeaker by simple filling with porous material and introduces a comprehensive method for evaluating gas adsorption–desorption dynamics in porous media.

Hydrocarbon-Impacted Soils Supported Mn for Organic Pollutant Oxidation

Hydrocarbon-impeded soil (HIS) is solid waste from spills or leaks during industrial activities that negatively impact the environment. This study aims to utilize HIS as catalyst support on MnO2 to degrade RhB (RhB) solution using Peroxymonosulfate (PMS) and to determine the optimum conditions for the catalyst to degrade RhB. The catalyst was synthesized by reacting HIS, calcined with KMnO4 with various catalyst supports with high and low Total contain Petroleum Hydrocarbon (TPH). The process degradation of Rhodamine Solution was carried out with various catalysts, PMS, and RhB concentrations. The catalyst was characterized using X-ray diffraction (XRD), Nitrogen gas adsorption-desorption (BET), and Scanning Electron Microscope-Energy Disperse Spectroscope (SEM-EDX). In this study, the best catalyst performance was MnO2@H-TPH, which could activate PMS to degrade RhB with dye removal of 98% in about 180 min, at conditions 10 g/L RhB, 0.1 g/L catalyst, and 3 g/L PMS with the activation energy of 16.3 kJ/mol.

Влияние механической обработки исходных реагентов на структурные и электрические свойства LiFeO2 керамики

This work investigates the effect of mechanical treatment of initial Fe2O3 and Li2CO3 powders on the structure and electrical properties of lithium ferrite ceramics of the chemical composition LiFeO2. Mechanical treatment was carried out in an AGO-2S ball mill for 60 minutes at a bowl rotation speed of 2220 rpm. Sintering of ceramic samples was carried out in a laboratory furnace at 1050 °C for 1 hour. Using X-ray phase analysis data, it was shown that the introduction of the mechanical treatment of powders leads to a decrease in the concentration of the α-LiFeO2 phase in ferrite ceramics from 97,9 to 93,9 wt.%, as well as an increase in the secondary LiFe5O8 phase from 2,1 to 6,1 wt.%. In this case, during sintering, a more homogeneous and finely porous structure of the samples was formed. Based on the temperature dependences of the electrical conductivity of the samples, it was established that changes in electrical resistance are associated both with the microstructure and with the processes of adsorption-desorption (depending on temperature) of gas from the surrounding atmosphere into ferrite ceramics. The ferrite ceramics obtained by mechanical treatment is of interest for its further use as an adsorption material for carbon oxides.

Adjustable gas adsorption and desorption via a self-shrinking nanoscroll

In a gas adsorption–desorption process, gas desorption consumes energy, as well. Hence, the development of gas adsorption–desorption methods and/or adsorbent materials with low-energy consumption for precisely controlling the reversible process is still an open issue. Taking carbon dioxide as an example, this study proposed a carbon nanospring as a unit of an adsorbent model to control the capacity for gas adsorption (CGA), via expanding for adsorption or self-shrinking for desorption by the nanoscroll made from partly hydrogenated graphene ribbon (H-GR). The numerical results obtained from the molecular dynamics approach demonstrate that the CGA of H-GR can be precisely controlled by changing the deformation of H-GR. The adjustable scope of CGA, called capacity for gas desorption, depends on the gas density and the loading speed. However, the ratio of desorption slightly depends on the gas density, which benefits gas capturing in potential application of the present material model.

Study on the Adsorption/Desorption Characteristics of Protogenetic CO in Coal Seams

ABSTRACT In recent years, abnormal CO gas overruns have often occurred in coal mining workings. CO overruns were thought to be caused by the underground blasting work or spontaneous combustion of coal seams; however, minimal attention has been given to the causes of the desorption and release of adsorbed CO in the coal seams. Additionally, insufficient research has been conducted on the generation, distribution and adsorption and desorption characteristics of protogenetic CO in coal seams. Therefore, a self-built comprehensive testing system for coal seam adsorption and desorption was used to study the characteristics of the depressurization desorption and thermal desorption of coal with different degrees of metamorphism during coal seam mining. The results showed that under isothermal conditions, the amount of CO adsorption and desorption of coal samples increased with increasing pressure; under temperature rise conditions, the gas adsorption-desorption was in a dynamic equilibrium process under certain conditions. When the temperature increased, the equilibrium was beneficial to the desorption direction. The initial temperature range of CO production at different equilibrium pressures was 45–55°C. With increasing pressure, the initial temperature point of CO gas production moves forward and was significantly lower than the initial temperature of coal spontaneous combustion. Our research results further supplement the source of underground protogenetic CO gas and provide theoretical support for the accurate prediction of CO coal spontaneous combustion.

Thickness-controlled porous NiO films by Ni(OH)2/alginate layer-by-layer assembly

Ni(OH)2/alginate multilayer thin films were prepared directly by dip-coating using Layer-by-Layer assembly method. β-Ni(OH)2 nanoplatelets were first synthetized by chemical precipitation from nickel nitrate in ammonia under ultrasound. These particles, stabilized at pH ≈ 8, present an equivalent diameter of ≈ 250 nm and a zeta potential of ≈ + 35 mV. Sodium alginate was used as a negatively charged polyelectrolyte. In this work, the multilayer growth was first investigated in situ using optical fixed-angle reflectometry showing that particles/polyelectrolyte multilayer film can be successfully carried out. Ni(OH)2/alginate multilayer thin films were elaborated using several parameters: number of adsorbed bilayers, alginate and Ni(OH)2 particles concentrations, showing that multilayer films thickness can be mainly controlled by the number of adsorbed bilayers. The elaborated films were then heated at 325 °C in air for 1 h to calcinate the incorporated polyelectrolyte and to form NiO films. Thermal treatment experiments show an alginate content-dependent film adhesion. Indeed, multilayer films are more adherent and homogeneous with low alginate concentration (< 0.2 g.L−1). Finally, the specific surface area (SSA) of the NiO films was determined by adsorption-desorption of nitrogen gas using BET method.

Mesoporous NiCo2O4 microspheres combining abundant oxygen vacancies for high-performance xylene gas sensor

In this study, the mesoporous NiCo2O4 microspheres with abundant oxygen vacancies were prepared through a concise solvothermal-calcination method. The result revealed that the mesoporous 500-NiCo2O4 sensor showed a high gas sensing response of 16.7 to 100 ppm xylene, and rapid response-recovery process and long-term stability. These can be attributed to the synergistic effect between mesoporous structure and oxygen vacancy, which not only facilitated the gas adsorption–desorption process but also offered more active sites to ionize more oxygen species, leading to an efficient gas sensing reaction.

Zinc(II)-Based Ring-and-Rod Coordination Layer as an Excitation-Wavelength-dependent Dual-Emissive Chemosensor for Discriminating Fe3+, Cr3+, and Al3+ in Water.

The reactions of Zn(NO3)2, 3,6-bis(pyridin-3-yl)-9H-carbazole (bpycz), and 2,5-dihydroxyterephthalic acid (H4dhbdc) or 2-bromoterephthalic acid (Br-1,4-H2bdc) under hydro(solvo)thermal conditions yielded corresponding coordination polymers (CPs) {[Zn(H2dhbdc)(bpycz)]•0.5H2O}n (1) and [Zn(Br-1,4-bdc)(bpycz)]•2DMAc•H2O (2), respectively, with high thermal stability approaching 350 °C. CP 1 adopts a ring-and-rod layer structure, which is topologically described as a 4-connected net with the point symbol of 2•65. Two layers are interpenetrated in parallel interlocking mode to form a double 2D → 2D polyrotaxane entanglement with extra-framework void space of 19.6%. CP 2 has a non-interpenetrating ring-and-rod layer structure of 4-connected 2•65 net topology, with extra-framework void space of 16.6%. Thermally activated 1 and 2 revealed CO2 uptakes of 101.1 and 98.6 cm3 g-1, respectively, at P/P0 = 1 and 195 K. X-ray powder diffraction (XRPD) patterns confirmed that 1 and 2 both possessed high chemical stability in H2O, CH3OH, acetone, and DMF, and framework stability during gas adsorption-desorption. The H2O suspension of 1 displayed excitation-dependent dual-emissive properties, appearing at 432 nm upon excitation at 300 nm and at 528 nm upon excitation at 365 nm. Of note, 1 was capable of detection of Fe3+, Cr3+, and Al3+ ions in H2O, showing good anti-interference ability, excellent selectivity, and high sensitivity. More interesting, the dual-emissive properties make 1 to be an excellent luminescence chemosensor to screen Fe3+, Cr3+, and Al3+ from a pool of metal ions in H2O upon excitation at 300 nm via luminescence quenching effect and then discriminate Fe3+, Cr3+, and Al3+ upon excitation at 365 nm via luminescence quenching, unaltered, and enhancement responses, respectively. On the other hand, the H2O suspension of 2 demonstrated an excitation-independent emission appearing at around 430 nm, which could be utilized to sensitively detect Fe3+ and Cr3+ ions with good anti-interference ability and excellent selectivity via luminescence quenching effect. Further, 1 and 2 were recyclability and possessed cycling stability. The plausible sensing mechanisms for 1 and 2 toward Fe3+, Cr3+, and Al3+ were also explored in detail.