Enhanced CO2 Capture Research Articles

Thermal Analysis and Kinetic Investigation of Using a Hybrid Adsorption-hydration Method to Promote CO2 Capture

In this work, a hybrid adsorption-hydration method was utilized to promote CO2 capture. The CO2 capture performance in the fixed bed of coal particles was assessed at various water saturations (0%, 20%, 40%, 70%, and 100%), 277.15 K, and 3.2 MPa. It was found that gas consumption at 100% water saturation increased by 45% compared to that at 0% water saturation (dry coal particles). Moreover, as the water saturation increased, CO2 capture became dominated by hydrate formation rather than gas adsorption. The thermal analysis for CO2 capture at 0% and 100% water saturation detected the exothermic peaks associated with CO2 adsorption and CO2 hydrate formation, as well as the endothermic peaks corresponding to CO2 desorption and CO2 hydrate dissociation. This confirms that CO2 capture in the fixed bed of water-saturated coal particles consists of CO2 adsorption followed by hydrate formation. The morphologies of CO2 hydrate formation in the fixed bed of 100% water-saturated coal particles were observed, and the mechanism of CO2 capture using the hybrid adsorption-hydration method was illustrated based on the thermal analysis and kinetic investigations. It was also found that after the adsorption-hydration process, the average cumulative pore volume of the coal particles decreased by 14.47% compared to the original coal particles, and the micropores and mesopores were predominantly affected. Therefore, utilizing the hybrid adsorption-hydration process in a fixed bed of coal particles provides a promising method to enhance CO2 capture.

Surface interaction changes in minerals for underground hydrogen storage: Effects of CO2 cushion gas

Hydrogen (H2) offers a promising solution for the energy transition but storing it on a large scale at the surface poses significant technical and environmental challenges. Underground formations provide a practical alternative for large-scale H2 storage, yet understanding H2 behavior under various subsurface conditions is crucial for optimizing storage capacity and efficiency, which are influenced by rock properties such as wettability. This study addresses the gap in literature regarding the wettability of different minerals when CO2 was injected with H2 as a cushion gas. We examined the wettability of various mineral rocks in realistic subsurface circumstances. A series of wettability measurements were carried out using a captive drop instrument under high-pressure and high-temperature conditions, employing seven different minerals.Our findings reveal that mixed gas contact angles are significantly affected by temperature and pressure, with CO2 playing a crucial role in minimizing hydrogen trapping and enhancing CO2 capture in UHS and Carbon Capture, Utilization, and Storage (CCUS) projects. Higher CO2 mole fractions lead in increased contact angles due to the enhanced density and solubility of the gases, especially in basalt. Increasing the CO2 mole fraction from 25 % to 75 % at a constant pressure of 100 bar and temperature of 60 °C caused the contact angle of basalt with brine to rise from 54° to 86°. Pressure has a more pronounced effect on contact angle changes than temperature. For quartz rock in a 50 % H2 + 50 % CO2 mixture, the contact angle changes by 18° when the temperature increases from 20 °C to 80 °C at a constant pressure of 70 bar in distilled water. In contrast, the contact angle changes by 36° when the pressure increases from 10 bar to 100 bar at a constant temperature of 40 °C.These insights are essential for selecting suitable rock formations for underground gas storage, thereby supporting the advancement of hydrogen storage technologies. Furthermore, utilizing CO2 improves technical performance and environmental sustainability while also supporting international efforts to reduce greenhouse gas emissions. Overall, our results offer insightful information about the planning and operation of underground hydrogen storage systems, emphasizing the potential of CO2 to increase storage effectiveness and support carbon sequestration initiatives.

Elucidating flow-directed 98% CO2 absorption using millimeter-sized coiled flow inverters: Nanocellulose-aided sustainable scope

The Sustainable Development Goals (SDGs) adopted by the United Nations drive the global efforts to discover a sustainable carbon capture method for the reduction of anthropogenic CO2 emissions. Concentrated alkanolamine solutions are being used as CO2 capture mediums for batch processes amid several disadvantages, such as energy intensiveness and poor efficiency. In this work, millimeter-sized coiled flow inverters (CFI) have been explored as a point-source CO2 capture tool for highly efficient, continuous operations. Solvent and CO2 gas flow rates are found to dictate the slug flow regime and, more specfically, slug lengths. High interfacial area and residence time remain the driving factors for enhanced CO2 capture using CFI. About 98% CO2 absorption efficiency has been achieved for 3% aqueous diethanolamine solution in CFI . The efficacy of nanocellulose, a sustainable nanomaterial has been unearthed for CO2 capture at low flow rate.

Role of Intermolecular Interactions in Deep Eutectic Solvents for CO2 Capture: Vibrational Spectroscopy and Quantum Chemical Studies.

Recent research and reviews on CO2 capture methods, along with advancements in industry, have highlighted high costs and energy-intensive nature as the primary limitations of conventional direct air capture and storage (DACS) methods. In response to these challenges, deep eutectic solvents (DESs) have emerged as promising absorbents due to their scalability, selectivity, and lower environmental impact compared to other absorbents. However, the molecular origins of their enhanced thermal stability and selectivity for DAC applications have not been explored before. Therefore, the current study focuses on a comprehensive investigation into the molecular interactions within an alkaline DES composed of potassium hydroxide (KOH) and ethylene glycol (EG). Combining Fourier transform infrared (FT-IR) and quantum chemical calculations, the study reports structural changes and intermolecular interactions induced in EG upon addition of KOH and its implications on CO2 capture. Experimental and computational spectroscopic studies confirm the presence of noncovalent interactions (hydrogen bonds) within both EG and the KOH-EG system and point to the aggregation of ions at higher KOH concentrations. Additionally, molecular electrostatic potential (MESP) surface analysis, natural bond orbital (NBO) analysis, quantum theory of atoms-in-molecules (QTAIM) analysis, and reduced density gradient-noncovalent interaction (RDG-NCI) plot analysis elucidate changes in polarizability, charge distribution, hydrogen bond types, noncovalent interactions, and interaction strengths, respectively. Evaluation of explicit and hybrid models assesses their effectiveness in representing intermolecular interactions. This research enhances our understanding of molecular interactions in the KOH-EG system, which are essential for both the absorption and desorption of CO2. The study also aids in predicting and selecting DES components, optimizing their ratios with salts, and fine-tuning the properties of similar solvents and salts for enhanced CO2 capture efficiency.

Electrospun polyacrylonitrile nanofiber composites integrated with Al-MOF/mesoporous carbon for superior CO2 capture and VOC removal

Electrospun PAN nanofiber composites with integrated Metal-Organic Frameworks (MOFs) and mesoporous carbon (MPC) offer an efficient solution for CO2 capture and hydrocarbon removal. In this study, we synthesized a series of NH2-MIL-101(Al)@MPC composites using a solvothermal method and incorporated them into PAN nanofibers via electrospinning. The composites were characterized by FTIR, XRD, FESEM, XPS, mechanical properties and TGA, showing enhanced surface area and pore structure. NH2-MIL-101(Al) exhibited a BET surface area of 933.14 m2/g, crucial for selective absorption. The PAN/MOF@MPC nanofibers demonstrated improved mechanical properties and achieved a CO2 uptake of 6.35 mmol g−1 at 298 K and 0.55 bar. Additionally, the modified nanofibers demonstrated excellent static and dynamic adsorption capacities for volatile organic compounds (VOCs) like acetone and benzene. This study highlights the synergistic effects of combining MOFs and MPCs within electrospun nanofibers, resulting in materials with enhanced adsorption efficiency and mechanical stability. The work presents a novel approach by integrating MOF@MPCs into electrospun PAN nanofibers, significantly enhancing CO2 capture and VOC removal. This innovative combination not only improves the adsorption performance but also advances the mechanical properties of the nanofibers, showcasing a new strategy for developing high-performance materials for environmental remediation. The results offer strong potential for real-world applications in air purification and carbon sequestration.

Evaluation of calcium looping CO2 capture and thermochemical energy storage performances of different stabilizers promoted CaO-based composites derived from solid wastes

Calcium looping is considered as an important high-temperature cyclic CO2 capture and concentrated solar energy storage technology. However, the dramatic inactivation of CaO over multiple carbonation-calcination cycles has seriously restricted their practical applications. In this study, a series of metal oxide (i.e. TiO2, MgO, Al2O3 and ZrO2)-stabilized CaO-based materials with high cyclic stability derived from carbide slag were synthesized via a facile and cost-effective approach for simultaneously enhanced CO2 capture and thermochemical energy storage (TCES). The results suggest that CCS-H-TiO2 exhibits high initial CO2 uptake of 0.41 gCO2/gsorbent, superior cyclic stability with an average attenuation of 1.71 %/cycle and remarkably stable energy storage density. CCS-H-Al2O3 shows the best stability with lowest attenuation rate of 9.6 %. Except for CCS-H-MgO, the stabilizers reacted with active calcium to form new phases and used as physical “barrier” and high-TT skeleton to offset the sintering stress, retain the microporous structures, hinder the excessive agglomeration and alleviate sintering.

Optimizing CO2 Capture Efficiency: Harnessing IoT and Industry 4.0 for Precise Temperature Analysis in Packed Absorption Columns

The deployment of various technologies to mitigate climate change is crucial for developing techniques that advance climate action. Climate change is exacerbated by rising levels of carbon dioxide (CO2) and other greenhouse gases, deforestation, and the use of fossil fuels. Urgent measures are needed to enhance CO2 capture efficiency, in alignment with the Sustainable Development Goals (SDGs) and climate action initiatives. This study investigates the influence of temperature variations in a packed absorption column on CO2 capture efficiency. By employing Internet of Things (IoT) and Industry 4.0 principles, it facilitates precise data acquisition to monitor temperature fluctuations during experiments. Comparative evaluations under steady-state and saturation conditions provide critical insights for optimizing CO2 capture in post-combustion processes. Conducting exploratory analyses enhances system understanding and informs design and operational strategies for effective and sustainable CO2 capture. This research delves into the technical aspects of temperature optimization, emphasizing its significance for sustainable practices and the urgency of addressing climate change through innovative, technology-driven solutions.

Tailoring porosity: Unveiling the ideal alumina support (aerogel, xerogel, cryogel) for high-performance CO2 capture with polyethylene glycol

This study investigates enhancing CO2 capture through high polyethylene glycol (PEG) loading on alumina aerogel (Al2O3-A), comparing it with alumina cryogel (Al2O3-C) and xerogel (Al2O3-X). Focusing on sustainable carbon capture and storage (CCS), the research optimizes PEG’s CO2 adsorption by adjusting the porosity of these alumina supports. Key characterization techniques, including XRD, FESEM, FTIR, and N2 adsorption-desorption analysis, were utilized. The study evaluated the effects of pressure, temperature, and PEG loading on CO2 capture capacity using response surface methodology (RSM). Optimal conditions (25 °C, 9.0 bar, 61.0 % PEG) achieved a CO2 adsorption capacity of 443 mg/g. The Hill model was most effective in describing the CO2 adsorption, while the fractional order model accurately depicted the kinetics. Thermodynamic analysis confirmed that the adsorption process is spontaneous, exothermic, and physical. The results underscore the potential of PEG/Al2O3-A for effective CO2 capture, highlighting its high stability, capacity, and reusability, and advancing sustainable carbon capture technologies.

Comparative Review for Enhancing CO2 Capture Efficiency with Mixed Amine Systems and Catalysts.

This study investigates methods to enhance the efficiency of CO2 capture using organic amine absorption and compares the performance of traditional and novel amine solvents. It reviews various single-component and mixed amine absorbents, as well as catalysts used in these methods, highlighting the superiority of mixed amine absorbents over single-component amine absorbents in CO2 absorption and desorption. Additionally, the study explores the catalytic mechanisms and effects of catalysts in the CO2 absorption/desorption process with amine solvents and provides an outlook on future research directions. The aim is to promote the widespread adoption of organic amine absorption technology in industrial applications and to contribute to the development of more sustainable and efficient CO2 capture technologies.

Li/Na/K carbonate solar salts for enhanced and integrated carbon capture and utilization via reverse water gas shift (ICCU-RWGS)

This study introduces a novel ICCU-RWGS process using Li, Na, and K carbonates mixed with boric acid as dual functional materials, enhancing CO2 capture and conversion without traditional CaO adsorbents. These molten salts, compatible with solar energy systems, enable efficient integration with CSP, storing heat from CO2 capture for utilization. The addition of boric acid significantly boosts CO2 uptake and conversion, achieving 2.0 mmol, 1.1 mmol, and 1.3 mmol CO2 uptake with conversion of 51.1 %, 58.3 %, and 57.6 % over three cycles, respectively. A 10-cycle test confirmed stable performance, with conversion rates between 53.0 % and 58.7 %. Characterization techniques (XRD, SEM, TEM, XPS, in-situ DRIFTS) revealed new borate phases after CO2 capture. TG-DSC analysis showed exothermic peaks during CO2 capture and RWGS stages, indicating that molten salt has the potential to generate heat for CSP systems, thus offering efficient CO2 conversion and sustainable energy recovery.

A Data-Driven Approach for Enhanced CO2 Capture with Ruthenium Complexes.

To attain carbon neutrality, significant efforts have been made to capture and utilize CO2. The homogeneous hydrogenation of CO2 catalyzed by transition metal complexes, particularly the ruthenium complexes, has demonstrated significant advantages and is regarded as a viable approach for practical application. Insertion of CO2 into the Ru-H bond, producing the Ru-formate product, is the key step in the hydrogenation of CO2. In order to parameterize the catalytic activities in the CO2 insertion into the Ru-H bond, the concept of simplified mechanism-based approach with data-driven practice (SMADP) has been introduced in this paper. The results showed that the hydricity of the Ru-H complex (ΔGH-) might serve as a single active descriptor in the process of CO2 insertion, and that a novel ruthenium complex in CO2 catalysis may not be easily obtained by mere modification of the auxiliary ligand at the ruthenium metal site.

Environmental factors affecting accelerated carbonation of recycled concrete aggregates using response surface methodology

To further enhance CO2 capture and sequestration in concrete waste, this study investigates the interaction of four environmental factors, i.e., temperature, relative humidity (RH), CO2 concentration and pressure on the accelerated carbonation of recycled concrete aggregates. 29 groups of accelerated carbonation tests are performed based on the Box-Behnken design. The effects of four factors on the carbonation percentage of recycled concrete aggregates (RCAs) are analyzed using a response surface methodology. A response surface model is obtained to characterize the experimental results. Additionally, three single-factor scenarios and three multi-factor coupled scenarios are employed to show the mechanisms affecting RCA carbonation and carbonation environments. Single factor analysis indicate that RH and CO2 concentration can significantly affect the carbonation of the RCA and the significance of the interactions follows the order of temperature - RH, RH - CO2 concentration and temperature - CO2 concentration. The microstructure of RCAs during carbonation is further studied and presented.

A porous phenolic resin sorbent for enhanced CO2 capture: Synthesis, optimization, and techno-economic analysis

Amidst rising global concerns about climate change, the capture and sequestration of carbon dioxide (CO2) from industrial emissions is becoming increasingly critical. In the present study, a phenolic resin-based porous polymer for CO2 capture is developed, offering a solution to the dual challenges of efficacy and cost in current carbon capture technologies. Optimization of synthesis parameters, including temperature, reaction time, and catalyst amount was performed using response surface methodology (RSM) to maximize surface area and economic benefits. The optimized polymer demonstrated a substantial CO2 adsorption capacity of 3.06 mmol/g at 273 K and 1 bar, with a specific surface area of 860 m2/g. An early-stage techno-economic analysis of sorbent synthesis was conducted, relating cost to sorbent quality and surface area. It was found that producing the polymer at low temperatures is more cost-effective, while synthesis at higher temperatures offers operational advantages. This research addresses a gap in existing literature by focusing on the sorbent material and its economic viability, paving the way toward the commercialization of such adsorption technology.

Enhanced CO2 capture by functionalization of SBA-15 with APTES and l-lysine

In this study, amine-based CO2 sorbents were synthesized after functionalizing SBA-15 mesoporous materials. Mesoporous SBA-15 was characterized and functionalized by APTES as an alkanolamine, L-lysine as an amino acid and a combination of both. CO2 adsorption tests were performed at 1.6 and 2 bar to estimate the carbon dioxide (CO2) uptake on the sorbents. As expected, CO2 adsorption capacity (mmol/g) increases with pressure. Based on the elemental analysis of the sorbents and the results of Fourier transform infrared spectroscopy (FTIR), a proposal was made of the possible chemical reactions that may occur in order to describe the experimental results. It is important to mention that the pretreatment prior to the CO2 adsorption tests plays a key role for the application of amine-functionalized mesoporous silica. The presence of water conditions the formation of carbonic acid and carbonate adsorbed on the surface and, consequently, the CO2 adsorption capacity of the sorbent. APTES and l-lysine loaded onto mesoporous SBA-15 exhibited the highest CO2 adsorption capacity (4.53 mmol/g) at 2 bar and room temperature. After reloading the sorbents with APTES and Lysine, no improvements in the CO2 absorption capacity were observed.

Deciphering the transfer mechanisms for CO2 absorption into binary blended solutions

A thorough understanding of the mechanisms involved in CO2 chemical absorption is crucial for the development of efficient CO2 capture technologies. Due to the insufficient insight into the interaction mechanism of different components in blended solutions, CO2 absorption reactions were often categorized as unidirectional transfer between absorption products. In this study, the CO2 absorption performance of binary blended solutions, including piperazine (PZ)/n-methyldiethanolamine (MDEA), ethanolamine (MEA)/MDEA, ammonia (NH3)/MDEA, PZ/potassium carbonate (K2CO3), and NH3/K2CO3, was investigated using a combination of experimental and computational methods. The CO2 absorption mechanisms of “competitive reaction”, “transfer reaction” and “parallel reaction” in the binary blended solution system were proposed. Kinetic experiments revealed that different blended solutions had varying impacts on the process of CO2 absorption. Among them, PZ/MDEA and MEA/MDEA solutions reduced the absorption rates by an average of 8% and 25%, respectively, compared to PZ or MEA component solutions. NH3/MDEA and PZ/K2CO3 solutions had absorption rates similar to those of single NH3/PZ component solutions. NH3/K2CO3 solutions, on the other hand, exhibited an average increase of 17% in absorption rates compared to NH3 solutions. Quantum mechanical (QM) methods were employed to evaluate of the absorption products and key processes in terms of kinetics and thermodynamics. Quantitative 13C NMR analyses were conducted to further investigate the interactions between components and the pathways of mass transport in blended solutions, which demonstrated proton transfer and CO2/-COO transfer between adsorption products. This study highlights an accurate description of the transfer mechanisms of various blended systems for the enhanced CO2 capture.

Study on K-modified Ca-based dual-functional materials for carbon capture and in-situ methane dry reforming

Integrated carbon capture and in-situ methane dry reforming (ICCU-DRM) is a promising technology for chemical looping transformation, this process involves the sequential switching of feedstocks within a single reactor, allowing CO2 capture to occur before methane dry reforming without direct CO2-CH4 contact. However, a significant challenge in the ICCU-DRM process is the disparity between the optimal temperatures required for carbon capture and dry reforming, with the latter necessitating considerably higher temperatures. This could lead to substantial CO2 losses when the reaction temperature is elevated to the optimal level for dry reforming. To address this issue and improve CO2 conversion efficiency, this study explores K doping in synthesizing a dual-functional material, NiCa1.6K0.4@Al2O3, through extrusion-spheronization. The synthesized material exhibits a stable pore structure and a large internal surface area, crucial for enhancing CO2 capture. The optimum temperature for DRM is around 800 °C. Notably, the formation of 1K2Ca(CO3)2 during the calcination of NiCa1.6K0.4@Al2O3, with a thermal decomposition temperature of approximately 800°C, plays a crucial role in minimizing CO2 release during the heating process, thereby significantly improving the CO2 conversion. To evaluate the impact of K doping on the material, the samples were subjected to carbon capture at 650 °C and dry reforming of methane at 750 °C. The results showed that the CO2 conversion rate of NiCa1.6K0.4@Al2O3 reached 52.8%, compared to only 18.9% for NiCa2@Al2O3 under the same conditions. Moreover, this study also investigates the impact of carbon capture temperature, dry reforming temperature, and catalytic metal loading on the performance of the ICCU-DRM process.

A Mathematical Model for Enhancing CO2 Capture in Construction Sector Using Hydrated Lime

A Mathematical Model for Enhancing CO2 Capture in Construction Sector Using Hydrated Lime

In-situ co-growth of ZIF-8-derived bio-carbon spheres with meso-macroporous hierarchy for stable and rapid carbon dioxide capture

Efficient carbon dioxide (CO2) capture from post-combustion flue gases is crucial for industrial applications. Adsorbents with high adsorption capacity, exceptional stability, high selectivity, and low cost are essential to meet these requirements. In this study, we present the synthesis of bio‑carbon spheres derived from zeolitic imidazolate framework-8 (ZIF-8) using a macro-fluidic technique. The bio‑carbon spheres integrate ZIF-8 for structural orientation and chitosan for the directional assembly of ZIF-8, thereby addressing the limitations of low strength in chitosan-derived carbon spheres and the challenge of macroscopic shaping of ZIF-8 particles. Additionally, the incorporation of ZIF-8 and the enhancement of the carbon skeleton increased the meso-macroporosity, improving CO2 transport and adsorption performance. The bio‑carbon spheres demonstrated a 46.9% higher CO2 adsorption capacity (101 kPa, 1.40 mmol·g−1) compared to pure chitosan carbon granules (101 kPa, 0.96 mmol·g−1) and a 17.8% faster mass transport rate compared to ZIF-8 carbon particles. Moreover, the bio‑carbon spheres exhibit a low wear rate in a simulated fluidized bed, good thermal stability, and stable cyclic regeneration performance. This study offers a novel strategy for developing industrially applicable adsorbents with hierarchical pore structures to enhance CO2 capture.

Optimized Porous Carbon Particles from Sucrose and Their Polyethyleneimine Modifications for Enhanced CO2 Capture

Carbon dioxide (CO2), one of the primary greenhouse gases, plays a key role in global warming and is one of the culprits in the climate change crisis. Therefore, the use of appropriate CO2 capture and storage technologies is of significant importance for the future of planet Earth due to atmospheric, climate, and environmental concerns. A cleaner and more sustainable approach to CO2 capture and storage using porous materials, membranes, and amine-based sorbents could offer excellent possibilities. Here, sucrose-derived porous carbon particles (PCPs) were synthesized as adsorbents for CO2 capture. Next, these PCPs were modified with branched- and linear-polyethyleneimine (B-PEI and L-PEI) as B-PEI-PCP and L-PEI-PCP, respectively. These PCPs and their PEI-modified forms were then used to prepare metal nanoparticles such as Co, Cu, and Ni in situ as M@PCP and M@L/B-PEI-PCP (M: Ni, Co, and Cu). The presence of PEI on the PCP surface enables new amine functional groups, known for high CO2 capture ability. The presence of metal nanoparticles in the structure may be used as a catalyst to convert the captured CO2 into useful products, e.g., fuels or other chemical compounds, at high temperatures. It was found that B-PEI-PCP has a larger surface area and higher CO2 capture capacity with a surface area of 32.84 m2/g and a CO2 capture capacity of 1.05 mmol CO2/g adsorbent compared to L-PEI-PCP. Amongst metal-nanoparticle-embedded PEI-PCPs (M@PEI-PCPs, M: Ni, Co, Cu), Ni@L-PEI-PCP was found to have higher CO2 capture capacity, 0.81 mmol CO2/g adsorbent, and a surface area of 225 m2/g. These data are significant as they will steer future studies for the conversion of captured CO2 into useful fuels/chemicals.

Investigations of Functional Groups Effect on CO2 Adsorption on Pillar[5]arenes Using Density Functional Theory Calculations

AbstractThis study investigates how various functional groups affect the adsorption of carbon dioxide (CO2) in pillar[5]arenes (P[5]A) at the aim of enhancing CO2 capture in P[5]A for environmental applications. Density functional theory (DFT) and density‐functional‐based tight‐binding (DFTB) methods were employed to investigate the adsorption behavior of CO2 in pillar[5]arenes (P[5]A) with various functional groups including P[5]A with methyl (P[5]A‐OCH3), aldehyde (P[5]A‐OCOH) functional groups and pillar[5]quinone (P[5]Q). Self‐consistent charge DFTB calculations have been performed using the DFTB+ code, with dispersion corrections included for van der Waals interactions, to ensure accurate results at a lower computational cost. Bader charge analysis have been carried out with VASP code to understand the interaction mechanisms and charge transfer between P[5]A and CO2. The study demonstrates that changing the functional groups of P[5]A affects CO2 adsorption behavior. Specifically, CO2 adsorption is more favorable at the cavity site of P[5]A‐OCH3 compared to other functional groups, due to the combined effects of weak hydrogen bonds and π‐π interactions. The calculated results shows that the functionalization is one of the beneficial factors for CO2 capture in pillararenes, the adsorption energy and configuration of adsorbed CO2 at P[5]A are affected by both the polarization and geometry of the functional groups. Furthermore, the density of states (DOS) calculations confirm that CO2 is only physisorbed in P[5]A, ensuring the reusability of pillararenes after desorption. The findings of this study suggest that modifying the functional groups of pillararens is a promising strategy for developing high‐efficiency CO2 capture materials.