Adsorption-desorption Behavior Research Articles

Adsorption–Desorption Behaviors of Enrofloxacin and Trimethoprim and Their Interactions with Typical Microplastics in Aqueous Systems

Adsorption–Desorption Behaviors of Enrofloxacin and Trimethoprim and Their Interactions with Typical Microplastics in Aqueous Systems

Evaluation of anion exchange resin for sorption of selenium (IV) from aqueous solutions

In this work, selenium (IV) ions were adsorbed from aqueous solutions by the strongly basic anion exchange resin Amberlite IRA-400. The morphology of the resin before and after Se(IV) sorption was investigated using different techniques such as energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). To determine the ideal sorption conditions, a batch approach was used to examine the variables affecting Se(IV) sorption performance, including pH, shaking time, adsorbent dosage, initial metal ion concentration, and temperature. The results showed the optimal parameters for the highest percentage of selenium (80.25%) at an initial concentration of 100.0 mg L−1, pH 3.0, the adsorbent dosage of 10.0 mg, and the shaking time of 60.0 min. According to the experimental findings, the sorption process was satisfactorily explained by the pseudo-second-order kinetic model. The maximum adsorption capacity at pH 3.0 was 18.52 mg g−1, and the adsorption rather well followed the Langmuir adsorption isotherm. Moreover, exothermic and spontaneous sorption reaction was the result of thermodynamic properties (negativity of both ΔG° and ΔH°). The adsorption phase's random distribution of the resin-solution interface is indicated by the positive value of ΔSo. Finally, the desorption study was performed using different concentrations of desorbing agents; HNO3, HCl, and sodium acetate. The results illustrated that the effective desorbing agent was 1.0 mol L-1 HNO3, with desorption efficiency reaching about 96.4%. Finally, the Amberlite IRA-400 demonstrated excellent adsorption–desorption behavior over five times, suggesting that the Amberlite IRA-400 could be an effective candidate for the sorption of Se(IV) from several metal ions that occur in fission products.

Adsorption-desorption of propyrisulfuron in six typical agricultural soils of China: kinetics, thermodynamics, influence of 38 environmental factors and its mechanisms.

Propyrisulfuron, a novel sulfonylurea herbicide, effectively suppresses intracellular acetolactate synthase activity for weed control, but its adsorption behavior in the soil environment remains unclear. To assess potential agroecosystem risks, the adsorption-desorption behavior and mechanism of propyrisulfuron in six typical agricultural soils of China were investigated using a batch equilibrium method, Density Functional Theory (DFT), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy equipped with Energy Dispersive X-ray (SEM-EDX) techniques. It is indicated that the adsorption-desorption of propyrisulfuron in six soils reached equilibrium at 36 hours under the optimum water-to-soil ratio (WSr) of 5:1. Adsorption kinetics followed the quasi-second-order kinetic model, while the Freundlich model best described the adsorption process at equilibrium. The adsorption and desorption were significantly and positively correlated with soil clay content, and 38 environmental factors had varying degrees of influence on its adsorption properties, especially those influenced by microplastics (MPs). Furthermore, the adsorption of propyrisulfuron in six soils was primarily a spontaneous, non-homogeneous, and non-ideal physical process, and special strong forces, such as hydrogen bonding might be involved. Consequently, due to its continuous application, potential persistent residues and pollution may occur in some soils. The investigations systematically reported the adsorption-desorption behavior of propyrisulfuron in various agricultural soils for the first time, providing scientific guidance for environmental risk assessment of groundwater pollution caused by its continuous application in agro-ecosystems.

Mechanistic insights into adsorption-desorption of PFOA on biochars: Effects of biomass feedstock and pyrolysis temperature, and implication of desorption hysteresis

Adsorptive removal of the emerging organic pollutant perfluorooctanoic acid (PFOA) from contaminated water using biochar is a promising cost-effective approach. To determine the stability of PFOA adsorption on biochar, the thermodynamic analysis of the adsorption-desorption behavior is essential. This study comprehensively investigated the adsorption and desorption of PFOA on biochars derived from maple sawdust, peanut shells and corn stalks, pyrolyzed at peak temperatures of 400, 600 and 800 °C. The findings indicated that the micropore volume of the biochars was key to PFOA adsorption, with peanut shell biochar produced at 800 °C showing the highest adsorption capacity of 16.75 mg/g, attributed to its larger micropore volume (0.22 m3/g). Thermodynamic analysis showed that the negative values of ∆G0 of PFOA adsorption ranged from −2.24 to −5.38 kJ/mol, confirmed that the process was spontaneous and involved physical pore-filling. However, the close similarity between the adsorption and desorption isotherms, coupled with a low hysteresis coefficient, clarified that the PFOA adsorption was unstable and prone to desorption. The thermodynamic insights from this study highlighted that lignin-rich biochar produced at high temperature with high micropore content was very favorable for the effective adsorptive removal of PFOA, while the long-term adsorption stability should not be overlooked in the remediation applications.

Desorption hysteresis in organic-rich formations: Implications for long-term carbon dioxide sequestration and hydrogen recovery factor

This study explores the potential of organic-rich formations for geo-storage of hydrogen and carbon dioxide using a novel molecular simulation workflow combing Grand Canonical Monte Carlo (GCMC) and Molecular Dynamics (MD) to delineate the interplay between pore structure, kerogen maturity, and the resulting adsorption–desorption behavior. The investigation utilizes two representative kerogen models – immature (II-A) and overmature (II-D) – to account for the inherent heterogeneity of organic-rich formations. The simulations demonstrate a direct correlation between kerogen maturity and gas sorption capacity. The overmature model, with its larger intermolecular spaces, exhibits a higher capacity for both H2 and CO2 compared to the immature one. Notably, CO2 displays a significantly stronger affinity towards the organic material, resulting in a much higher sorption capacity compared to H2 for both kerogen types. The key finding lies in the contrasting desorption profiles for H2 and CO2. H2 desorption exhibits minimal hysteresis, suggesting readily recoverable gas with minimal trapping within the kerogen structure. This signifies the potential for efficient H2 storage with minimal losses during retrieval stages. Conversely, CO2 desorption displays a pronounced hysteresis loop, indicating significant gas retention within the formation even at lower pressure. This behavior aligns perfectly with the objective of CO2 sequestration, where minimizing leakage risk is paramount. These contrasting effects of hysteresis on H2 storage and CO2 sequestration highlight the unique suitability of organic-rich formations for both applications. Additionally, the study suggests a potential link between kerogen maturity and the magnitude of the hysteresis loop. Such insights could be instrumental in selecting optimal formations for targeted geo-storage operations.

Dual Electric Field Coupling with Tunable Schottky Barrier Synergistically Regulating Electronic Configuration in CoP@Ni‐CdS Heterojunction for Efficient Photocatalytic H2 Evolution

AbstractDesigning and exploiting visible‐light‐responsive materials that converts solar into chemical energy is promising in achieving green energy sustainability, but addressing low electron–hole separation efficiency and sluggish surface kinetic process remains formidable challenges. Herein, a novel CoP@Ni‐CdS Schottky junction composed of Ni‐doped CdS nanorods and quasi‐metallic CoP nanoparticles is constructed via a simple hydrothermal–calcination method. Experiments and theoretical calculations demonstrate that magnetic Ni‐doping not only induces a spin‐polarized electric field and enhances the built‐in interfacial electric field strength, but also rises the Schottky barrier height at the heterointerface, which synergistically accelerates the separation efficiency of photoinduced charges and modulates the electronic configuration of the active site to optimize the adsorption–desorption behaviors for H2O molecules and H* intermediates. Therefore, the designed CoP@Ni‐CdS catalyst exhibits an exceptional photocatalytic performance with H2 evolution rate of 42.14 mmol g−1 h−1 with the apparent quantum efficiencies of 16.8% at 420 nm, which is 14.14 and 2.21 times higher than that of pristine CdS and Ni‐CdS, respectively. This work provides in‐depth insights into fabricating dual electric fields, tuning the Schottky barrier and modulating the electronic configuration of active sites in Schottky heterojunction for ameliorative photocatalytic activity.

Prussian Blue-Derived Atomic Fe/Fe3C@N-Doped C Catalysts Supported by Carbon Cloth as Integrated Air Cathode for Flexible Zn-Air Batteries.

The development of an integrated air cathode with superior oxygen reduction reaction (ORR) performance is fundamental to flexible zinc-air batteries (ZABs) for wearable electronics. Herein, a self-assembled metal-organic framework (MOF)-derived strategy is proposed to prepare a atomic Fe/Fe3C@N-doped C catalysts supported by carbon cloth (CC) catalyst for use as an air cathode of flexible ZABs. The Prussian Blue precursor, which self-assembles on the surface of the carbon cloth due to electrostatic attraction, is critical in achieving the uniform dispersion of catalysts with high density loading on carbon cloth substrates. The hollow cubic structure, N-doped carbon layer coating, and the integrated electrode design can provide more accessible active sites and facilitate a rapid electron transfer and mass transport. Density functional theory (DFT) calculation reveals that the electronic interactions between the Fe-N4 and Fe3C dual active sites can optimize the adsorption-desorption behavior of oxygen intermediates formed during the ORR. Consequently, the Fe/Fe3C@N-doped C/CC exhibits an excellent half wave potential (E1/2 = 0.903V) and superior long-term cycling stability in alkaline environments. With excellent ORR performance, ZABs and flexible ZABs based on Fe/Fe3C@N-doped C/CC air cathode demonstrate excellent overall electrochemical performance in terms of open circuit voltage, maximum power density, flexibility, and cycling stability.

Novel Lewis Acid-Base Interactions in Polymer-Derived Sodium-Doped Amorphous Si-B-N Ceramic: Towards Main-Group-Mediated Hydrogen Activation.

Interest is growing in transition metal-free compounds for small molecule activation and catalysis. We discuss the opportunities arising from synthesizing sodium-doped amorphous silicon-boron-nitride (Na-doped a-SiBN). Na+ cations and 3-fold coordinated BIII moieties were incorporated into an amorphous silicon nitride network via chemical modification of a polysilazane followed by pyrolysis in ammonia (NH3) at 1000 °C. Emphasis is placed on the mechanisms of hydrogen (H2) activation within Na-doped a-SiBN structure. This material design approach allows the homogeneous distribution of Na+ and BIII moieties surrounded by SiN4 units contributing to the transformation of the BIII moieties into 4-fold coordinated geometry upon encountering H2, potentially serving as frustrated Lewis acid (FLA) sites. Exposure to H2 induced formation of frustrated Lewis base (FLB) N-= sites with Na+ as a charge-compensating cation, resulting in the in situ formation of a frustrated Lewis pair (FLP) motif (≡BFLA⋅⋅⋅Hδ-⋅⋅⋅Hδ+⋅⋅⋅:N-(Na+)=). Reversible H2 adsorption-desorption behavior with high activation energy for H2 desorption (124 kJ mol-1) suggested the H2 chemisorption on Na-doped a-SiBN. These findings highlight a future landscape full of possibilities within our reach, where we anticipate main-group-mediated small molecule activation will have an important impact on the design of more efficient catalytic processes and the discovery of new catalytic transformations.

Adsorption–desorption behavior of pesticides in soil environment: a systematic review

Adsorption–desorption behavior of pesticides in soil environment: a systematic review

Adsorption and desorption of nonylphenol on the biodegradable microplastics in seawater

Biodegradable plastics have been widely used and their interaction with endocrine disrupting chemicals in the environment is worth exploring. This study selected poly (butylene adipate-co-terephthalate), poly (butylene succinate), polylactic acid (PLA) and a non-biodegradable microplastics (PE) as control to explore the adsorption-desorption behavior of nonylphenol (NP) on the biodegradable microplastics in seawater. The adsorption capacity of NP on PLA (60.78 μg g−1) was approximately 50% lower than that on PE (116.53 μg g−1) which was the non-biodegradable microplastic control. Almost all biodegradable microplastics showed negligible desorption capacity compared to PE, indicating a lower environmental risk of biodegradable microplastics. The pH could influence the interaction between the NP and biodegradable microplastics through the formation of hydrogen bonds. The adsorption-desorption capacity of microplastics might increase at the condition of the high salinity and seawater erosion. Physical adsorption was the major adsorption processes based on the Gibbs free energy changes that calculated. The adsorption mechanism of microplastics was determined by calculating the crystallinity of microplastics, simulating the surface electrostatic potential of microplastics and conducting hydrophilicity tests of microplastics. The adsorption and desorption capacities of NP on biodegradable microplastics were mainly influenced by various mechanisms, including the crystallinity of the microplastics, hydrogen bonding and hydrophobic effects. These results will offer new perspectives on the interaction between biodegradable microplastics and NP in the ocean.

Kinetics and sorption behavior of glyphosate and tricyclazole for their efficient retention in biomixtures

The present investigation aims to study adsorption-desorption behavior of glyphosate and tricyclazole in rice straw-compost biomixtures. To enhance pesticide adsorption and performance of the bio-purification system, rice straw-compost (BM) biomixture was mixed with wheat straw biochar (WBC, 1% and 5%), and adsorption of both pesticides in control (BM) and WBCBM(1%) and WBCBM(5%) biomixtures was compared. The kinetics study suggested that the pseudo-second-order model best explained the time-dependent adsorption of both pesticides and intraparticle adsorption was not the rate-determining step. Tricyclazole was more sorbed than glyphosate in all biomixtures which can be attributed to its lower water solubility. The WBC increased the sorption of both pesticides, but the effect varied with the nature of pesticides and biochar content. The adsorption coefficient values in BM, WBCBM(1%), and WBCBM(5%) biomixtures were 26.74, 38.16, and 51.97 (glyphosate) and 38.07, 59.94, and 84.54 (tricyclazole), respectively. The adsorption data was subjected to the Freundlich, the Langmuir, and the Temkin isotherms, and among them, the Freundlich isotherm best explained pesticide adsorption behavior. Desorption results suggested that the adsorption of glyphosate was more irreversible than tricyclazole and depended upon initial pesticide concentration. This study suggested that biochar mixed rice straw-compost biomixtures can be exploited in bio-purification systems for glyphosate and tricyclazole.

Effects of Heteroatom Doping on the Electrochemical Hydrogen Uptake and Release of Pd-Decorated Reduced Graphene Oxide.

Heteroatom doping has been widely recognized as a key strategy for improving the electrochemical properties of graphene-based materials for hydrogen storage. However, a precise understanding of how heteroatom doping influences catalytic performance, specifically regarding the intricate effects of doping-induced electron redistribution, has been lacking. Here, we report on a comprehensive exploration of the electrochemical performance enhancement in Pd-decorated reduced graphene oxide (rGO) nanocomposites through fluorine (F) or nitrogen (N) doping. Various analytical techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES), and extended X-ray absorption fine structure (EXAFS) were employed to thoroughly characterize the synthesized nanocomposites. The findings revealed that either F or N doping effectively addressed clustering issues of Pd nanoparticles formed on the rGO surface, resulting in improved homogeneity of Pd distribution. Electrochemical studies provided crucial insights into hydrogen adsorption-desorption behaviors. The heteroatom doped nanocomposites, Pd/N-rGO and Pd/F-rGO, exhibited superior electrochemical performance, which can be attributed to the increase of the active sites due to the N-/F-doping, respectively. The hydrogen discharge capacities of Pd/N-rGO (80.9 mAh g-1) and Pd/F-rGO (25.0 mAh g-1) nanocomposites were determined to be over 4.0 and 1.2 times higher than that of the Pd/rGO (20.1 mAh g-1), respectively. The distinctive electrochemical performances observed between the two types of heteroatom-containing nanocomposites highlight the subtle structural modifications of Pd nanoparticles as the key factor influencing performance. This research contributes essential knowledge to the evolving field of hydrogen storage materials, emphasizing the promising potential of heteroatom-doped Pd-decorated rGO nanocomposites for advancing clean and sustainable energy solutions.

Zinc Adsorption–Desorption Behavior and Sequential Extractable Pools in Sugarcane-Based Cropping Systems of Western Indo-Gangetic Plain

Zinc Adsorption–Desorption Behavior and Sequential Extractable Pools in Sugarcane-Based Cropping Systems of Western Indo-Gangetic Plain

Adsorption-desorption behavior of malachite green on aged microplastics in seawater environment

The role of microplastics (MPs) as carriers of contaminants in the water environment is an emerging concern, significantly impacting migration and transformation. This study aims to compare the adsorption behavior of MPs with Malachite green (MG) dye before and after simulated short-term seawater aging (especially during the initial phase of the aging process) and to analyze in-depth the mechanism by which the aging process influences adsorption behavior. Results showed that after aging, the adsorption capacities of Polypropylene (PP), Polyethylene terephthalate (PET), and Polyethylene (PE) for MG were 2.58, 2.43, and 1.59 mg g−1, respectively. The adsorption capacity of other MPs for MG increased significantly, except for PE, which remained nearly unchanged. Calcium chloride (CaCl2) plays a significant role in the seawater aging process, and increasing the concentration of CaCl2 leads to a decrease in the adsorption amount of MG. Additionally, the adsorption capacity for MG varies significantly across different particle sizes and types of MPs, as well as the adsorption capacity of PP for different dyes. The Langmuir and Freundlich models indicate that the adsorption aligns more with the Freundlich model, which suggests that adsorption primarily occurs as multi-layer adsorption on a non-homogeneous surface. These results provide a scientific foundation for evaluating the ecological and environmental risks when MPs and organic dyes coexist. We also propose a novel approach of “treating waste dye with MPs” to mitigate their pollution in the aquatic environment.

Strychnos potatorum seeds derived magnetic graphene oxide nanocomposite for removal of nickel from wastewater: Adsorption performance, isotherm, kinetic and desorption behavior

In the present study investigates the adsorption of nickel ions by Strychnos potatorum seeds derived magnetic graphene oxide (SP-MGO). The fitness of the derived material was analyzed using BET and zeta seizer which proves the suitability of this adsorbent for adsorption process. The surface area, pore size and pore volume were obtained through BET analysis and the results were 51.798 (m2/g), 16.795 nm and 0.217 (cm3/g) respectively. And the size of the nanoparticle was measured using zeta seizer. For achieving maximum adsorption capacity, the following optimized conditions were; 60 min of contact time, under pH of 8, with 10 mg of SP-MGO dose, for the concentration of 10 mg/l, at the temperature of 35 °C. Freundlich isotherm (R2 =0.999) and pseudo second order (R2 =0.997) was well described the adsorption process. According to the isotherm model the adsorption of nickel ions occurs by multilayer of adsorption on heterogeneous surface of SP-MGO nanoadsorbent and also by chemisorption according to kinetic model. The Langmuir monolayer adsorption capacity (Q max) obtained by SP-MGO was 6.66 mg/g. The regeneration ability of SP-MGO was only reduced 17.1 % even after five cycles of adsorption runs. Overall, the SP-MGO can be a potential option for develop into a commercial adsorbent for industrial use to eliminate the pollutants from waste water.

The adsorption–desorption behavior of 2,4-dichlorophenol on microplastics in waters with different salinity

The adsorption–desorption behavior of 2,4-dichlorophenol on microplastics in waters with different salinity

Asymmetrical anchor way of manganese atoms on carbon domain edge for enhanced oxygen reduction reaction

Single atomic catalysts (SACs), especially the catalysts featured by well-developed M-N4 moieties, show excellent catalytic activity and spark enormous attention. However, the highly symmetric active sites may result in some degenerate electronic states for the d orbitals of the center metal atom, which suffer from the unsatisfactory adsorption-desorption behaviors during reaction. Herein, we develop an asymmetric anchor site by two types of nitrogen (sp-N and pyridinic N) created in the inherent edge-rich carbon domain of hydrogen-substituted graphdiyne (HsGDY), where atomic catalyst like manganese atoms can be asymmetrically anchored on the one side of hexagon carbon rings. The abundant elegant hexagon carbon rings on HsGDY not only facilitate the creation of edge sites, but also provide available space for the coordination of terminal ligands (OH) with Mn atoms. The as-synthesized Mn-N-HsGDY exhibits excellent ORR activity and an impressive long-term cyclability for over 3800 cycles in a rechargeable Zn-air battery.

Preparation of UiO-66 membrane through heterogeneous nucleation assisted growth strategy for efficient CO2 capture under humid conditions

Metal-organic frameworks (MOFs) have driven the development of polycrystalline membranes in the field of gas separation owing to the strong adsorption-desorption behavior and stable framework structure. However, the poor heterogeneous bonding ability between crystals and the substrate leads to the unsatisfactory gas separation as well as low stability of MOF membranes, especially in the humid environment. Herein, we prepared a thin and defect-free UiO-66 membrane by a crystal heterogeneous nucleation assisted growth strategy for efficient CO2/N2 separation. The addition of small amount of water in the precursor solution promoted the crystal nucleation process on the substrate surface. Meanwhile, the smooth PDMS interlayer guaranteed the heterogeneous well-intergrown of crystals into thin UiO-66 membranes, and provided a hydrophobic environment. Therefore, the dense UiO-66 membrane with a small thickness exhibited a high CO2 permeance (177.4 × 10−9 mol·m−2·s−1·Pa−1) with moderate CO2/N2 selectivity (24.3) under humid conditions. Furthermore, the prepared membrane demonstrated excellent renewable performance after dehumidification at high temperature, and maintained good hydrothermal stability during long-term operation under the humid environment. This work provides a new insight for the design of high-quality MOF membranes and promotes the development of MOF membranes in practical gas separation process.

The adsorption-desorption behavior of chlorothalonil in the cuticles of apple and red jujube

The distribution fate of chlorothalonil (CHT) in the environment (soil and water) and fruits is controlled by the capacity of cuticles to adsorb and desorb CHT, which directly affects the safety of both the environment and fruits. Batch experiments were conducted to reveal the adsorption-desorption behaviors of CHT in the cuticles of apple and red jujube. The adsorption kinetics showed that both physisorption and chemisorption occurred during the adsorption process. Furthermore, the isothermal adsorption of CHT in the fruit cuticles followed the Freundlich model. The thermodynamic parameters (ΔG ≤ −26.16 kJ/mol, ΔH ≥ 31.05 kJ/mol, ΔS ≥ 0.20 kJ/(mol K) showed that the whole CHT adsorption process was spontaneous, and the hydrophobic interaction was predominant. The CHT adsorption capacity of the apple cuticle was higher than that of the red jujube cuticle, potentially due to the significantly higher alkanes content of apples than that of red jujubes. An appropriate ionic strength (0.01 moL/L) could induce a higher adsorption capacity. In addition, the desorption kinetics were shown to conform to a Quasi-first-order model, meaning that not all the adsorbed CHT could be easily desorbed. The desorption ratios in apple and red jujube cuticles were 41.38% and 35.64%, respectively. The results of Fourier-transformed infrared spectroscopy and X-ray photoelectron spectroscopy further confirmed that CHT could be adsorbed and retained in the fruit cuticles. Investigating the adsorption-desorption behavior of CHT in the apple and red jujube cuticles allowed to determine the ratio of its final distribution in the fruits and environment, providing a theoretical basis to evaluate the risk of residue pesticide.

Amine-impregnated natural inorganic nanotubes via layer-by-layer electrostatically self-assembly approach for efficient CO2 adsorption

Developing cost-effective and high-performance solid amine adsorbents has considered as an important way to alleviate the greenhouse effect. How to precisely regulate its pore structure and surface interface characteristics, and how to cooperate to optimize the dynamic mass transfer and adsorption–desorption behavior of gas in the adsorbent are still challenging work. Herein, we demonstrated a facile and efficient approach to construct polyethyleneimine (PEI) impregnated halloysite nanotubes (HNTs) as an emerging nanocomposite for CO2 capture. Based on the natural electrostatic differences of inner and outer walls for HNTs, the hollow tubular structures of adsorbents were constructed by selective surface modification and layer-by-layer electrostatic self-assembly technology to improve the CO2 uptake capacity and cyclic stability, in which poly(sodium-p-styrene sulfonate) (PSS) and PEI were used as polyanionic and polycationic layer, respectively, to coat the inner walls of HNTs. The loading capacity of PSS-PEI composite ionic layers in HNTs and the influence of PSS polyanionic layer on PEI dispersion were specifically discussed according to the CO2 uptake capacity, adsorption heat, thermodynamics and kinetics of the adsorbents. The optimal PEI20-0.5PHNTs adsorbent exhibited a higher CO2 uptake of 0.87 mmol/g at 80 °C in the flow of 40 vol% N2/60 vol% CO2 than that of PEI20-HNTs, owing to the high amine efficiency due to the uniform dispersion of PEI in the electrostatic composite ionic layers. Furthermore, PEI20-0.5PHNTs reached 75 % of the maximum adsorption capacity at the 5th min of the adsorption process and released the most heat during adsorption at − 18.28 kJ/mol due to the presence of electrostatic composite ionic layers. PEI20-0.5PHNTs showed excellent cyclic stability with a slight loss of 7.4 %. The electrostatic self-assembled adsorbent obtained by layer-by-layer loading of PSS and PEI based on the unique surface charge characteristics of HNTs is an inspiration for the synthesis of cost-effective solid amine adsorbents for practical CO2 capture and separation.