The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Sumio Iijima - One of the best experts on this subject based on the ideXlab platform.
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boron and nitrogen doped single walled carbon Nanohorns with graphite like thin sheets prepared by co2 laser ablation method
Carbon, 2017Co-Authors: Ryota Yuge, Shunji Bandow, Masako Yudasaka, Sumio Iijima, Kiyohiko Toyama, Takashi ManakoAbstract:Abstract Boron- and nitrogen-codoped single walled carbon Nanohorns (BN-SWCNHs) were prepared by CO 2 laser ablation of a boron-containing carbon target under nitrogen atmosphere. The structures were spherical SWCNH aggregates containing many graphite-like thin sheets (GLSs), which was different from general SWCNHs. X-ray photoelectron spectra indicated that the doped quantities of boron and nitrogen were about 1.2 and 1.0 at.%, respectively. The boron and nitrogen atoms were implanted partially as the BN bonding in a graphene lattice, although they were also implanted individually as three-fold coordinated sp 2 bonding. The boron-doped GLSs were preferentially prepared by CO 2 laser ablation of a boron-containing carbon target under argon atmospheres. As a result, we found that the boron accelerated the formation of GLSs. The simple CO 2 laser ablation method will be useful for heteroatoms doping into carbon Nanohorns.
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ethane adsorption on aggregates of dahlia like Nanohorns experiments and computer simulations
Physical Chemistry Chemical Physics, 2016Co-Authors: Brice Russell, Mercedes M Calbi, Aldo Migone, Masako Yudasaka, Justin Petucci, Sumio IijimaAbstract:This is a report on a study of the adsorption characteristics of ethane on aggregates of unopened dahlia-like carbon Nanohorns. This sorbent presents two main groups of adsorption sites: the outside surface of individual Nanohorns and deep, interstitial spaces between neighbouring Nanohorns towards the interior of the aggregates. We have explored the equilibrium properties of the adsorbed ethane films by determining the adsorption isotherms and isosteric heat of adsorption. Computer simulations performed on different model structures indicate that the majority of ethane adsorption occurs on the outer region of the aggregates, near the ends of the Nanohorns. We have also measured the kinetics of adsorption of ethane on this sorbent. The measurements and simulations were conducted along several isotherms spanning the range between 120 K and 220 K.
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structural modeling of dahlia type single walled carbon Nanohorn aggregates by molecular dynamics
Journal of Physical Chemistry A, 2013Co-Authors: L. Hawelek, A Brodka, Tomonori Ohba, John C. Dore, Masako Yudasaka, Sumio Iijima, Katsumi Kaneko, Alex C. Hannon, Agata BurianAbstract:The structure of dahlia-type single-walled carbon Nanohorn aggregates has been modeled by classical molecular dynamics simulations, and the validity of the model has been verified by neutron diffraction. Computer-generated models consisted of an outer part formed from single-walled carbon Nanohorns with diameters of 20–50 A and a length of 400 A and an inner turbostratic graphite-like core with a diameter of 130 A. The diffracted intensity and the pair correlation function computed for such a constructed model are in good agreement with the neutron diffraction experimental data. The proposed turbostratic inner core explains the occurrence of the additional (002) and (004) graphitic peaks in the diffraction pattern of the studied sample and provides information about the interior structure of the dahlia-type aggregates.
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co2 adsorption on dahlia like carbon Nanohorns isosteric heat and surface area measurements
Journal of Physical Chemistry C, 2012Co-Authors: Vaiva Krungleviciute, Aldo Migone, Masako Yudasaka, Sumio IijimaAbstract:We present the results of an adsorption study of carbon dioxide on closed dahlia-like single-walled carbon Nanohorn aggregates. The study was conducted to explore the sorptive capacity of the Nanohorns and the dependence of the CO2’s isosteric heat of adsorption on sorbent loading. We found that there are no steps present in the carbon dioxide isotherms and that the isosteric heat of adsorption has an unusual nonmonotonic dependence on loading. Both of these behaviors are opposite to what is observed for other simple gases (argon, methane, neon, etc.) adsorbed on the same sorbent. The effective specific surface area of the Nanohorn aggregates was determined using the BET and point-B methods.
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Electronically modified single wall carbon Nanohorns with iodine adsorption
Chemical Physics Letters, 2011Co-Authors: Fitri Khoerunnisa, Tomonori Ohba, Toshihiko Fujimori, Hirofumi Kanoh, Tsutomu Itoh, Masako Yudasaka, Sumio Iijima, Katsumi KanekoAbstract:Abstract Tailoring electronic properties of single wall carbon Nanohorn (SWCNH) is expected to develop the application potential in various fields. SWCNH is efficiently modified with iodine molecules by liquid phase adsorption. The adsorption isotherm of iodine on SWCNH was Langmuirian with the saturated adsorption amount of 185 ± 10 mg g−1 (coverage 0.18), indicating a specific interaction between SWCNH and iodine. The DC electrical conductivity of SWCNH film prepared by dip-coating method increased with the iodine adsorption amount almost by a factor 10.
Masako Yudasaka - One of the best experts on this subject based on the ideXlab platform.
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carbon Nanohorn liposome systems preformulation design and in vitro toxicity studies
Materials Science and Engineering: C, 2019Co-Authors: Natassa Pippa, Christina Stangel, Ioannis Kastanas, Efstathia Triantafyllopoulou, Nikolaos Naziris, Dimitris Stellas, Masako Yudasaka, Minfang Zhang, Costas DemetzosAbstract:Abstract In the present work, the convergence of two different drug delivery systems is investigated, namely the combination of carbon Nanohorns (CNHs) and liposomes. Our effort initially included the synthesis of two conversely charged carbon Nanohorns and their subsequent analysis through various methods. The study of their effect on the thermotropic behavior of artificial membranes provided an essential assistance for the upcoming liposome preparation, which were estimated for their physicochemical properties. The presence of CNHs alters the calorimetric parameters of the lipids. We also prepared CNHs:liposome systems. The characteristic morphology and secondary spherical superstructure of CNHs is retained in the chimeric materials, suggesting that the interactions with the liposomes do not alter the dahlia-flower-like aggregation of CNHs. Both CNHs-liposome systems exhibit a relatively small cellular cytotoxicity in vitro, tested in mouse embryonic fibroblasts. To summarize, we developed CNHs:liposome platforms with a complete knowledge of their thermotropic, physicochemical, morphological and nanotoxicological characteristics.
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boron and nitrogen doped single walled carbon Nanohorns with graphite like thin sheets prepared by co2 laser ablation method
Carbon, 2017Co-Authors: Ryota Yuge, Shunji Bandow, Masako Yudasaka, Sumio Iijima, Kiyohiko Toyama, Takashi ManakoAbstract:Abstract Boron- and nitrogen-codoped single walled carbon Nanohorns (BN-SWCNHs) were prepared by CO 2 laser ablation of a boron-containing carbon target under nitrogen atmosphere. The structures were spherical SWCNH aggregates containing many graphite-like thin sheets (GLSs), which was different from general SWCNHs. X-ray photoelectron spectra indicated that the doped quantities of boron and nitrogen were about 1.2 and 1.0 at.%, respectively. The boron and nitrogen atoms were implanted partially as the BN bonding in a graphene lattice, although they were also implanted individually as three-fold coordinated sp 2 bonding. The boron-doped GLSs were preferentially prepared by CO 2 laser ablation of a boron-containing carbon target under argon atmospheres. As a result, we found that the boron accelerated the formation of GLSs. The simple CO 2 laser ablation method will be useful for heteroatoms doping into carbon Nanohorns.
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ethane adsorption on aggregates of dahlia like Nanohorns experiments and computer simulations
Physical Chemistry Chemical Physics, 2016Co-Authors: Brice Russell, Mercedes M Calbi, Aldo Migone, Masako Yudasaka, Justin Petucci, Sumio IijimaAbstract:This is a report on a study of the adsorption characteristics of ethane on aggregates of unopened dahlia-like carbon Nanohorns. This sorbent presents two main groups of adsorption sites: the outside surface of individual Nanohorns and deep, interstitial spaces between neighbouring Nanohorns towards the interior of the aggregates. We have explored the equilibrium properties of the adsorbed ethane films by determining the adsorption isotherms and isosteric heat of adsorption. Computer simulations performed on different model structures indicate that the majority of ethane adsorption occurs on the outer region of the aggregates, near the ends of the Nanohorns. We have also measured the kinetics of adsorption of ethane on this sorbent. The measurements and simulations were conducted along several isotherms spanning the range between 120 K and 220 K.
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multifunctional carbon Nanohorn complexes for cancer treatment
Chemistry-an Asian Journal, 2015Co-Authors: Svetlana A Chechetka, Sylvie Begincolin, Benoit P Pichon, Alberto Bianco, Masako Yudasaka, Minfang Zhang, Eijiro MiyakoAbstract:Multifunctional carbon Nanohorn (CNH) complexes were synthesized using oxidized CNH, magnetite (MAG) nanoparticles, and polyethyleneimine (PEI). The ferromagnetic MAG nanoparticles were loaded onto CNH (MAG-CNH) using iron(II) acetate and subsequent heat treatment. Chemical functionalization of the MAG-CNH complexes with PEI improved their water-dispersibility and allowed further conjugation with a fluorophore. The application of an external magnetic field significantly intensified the targeted vectorization of CNH complexes into human cervical cancer (HeLa) cells. Following cell uptake, laser irradiation of the cells showed a significant enhancement in the photothermal effects of CNHs leading to cell death. We have confirmed that the photothermal properties and ferromagnetic characteristics of CNH complexes show efficient cell elimination. The present study is an essential step toward the development of an innovative cancer therapy and a highly sensitive detection of cancer cells at the single-cell level.
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structural modeling of dahlia type single walled carbon Nanohorn aggregates by molecular dynamics
Journal of Physical Chemistry A, 2013Co-Authors: L. Hawelek, A Brodka, Tomonori Ohba, John C. Dore, Masako Yudasaka, Sumio Iijima, Katsumi Kaneko, Alex C. Hannon, Agata BurianAbstract:The structure of dahlia-type single-walled carbon Nanohorn aggregates has been modeled by classical molecular dynamics simulations, and the validity of the model has been verified by neutron diffraction. Computer-generated models consisted of an outer part formed from single-walled carbon Nanohorns with diameters of 20–50 A and a length of 400 A and an inner turbostratic graphite-like core with a diameter of 130 A. The diffracted intensity and the pair correlation function computed for such a constructed model are in good agreement with the neutron diffraction experimental data. The proposed turbostratic inner core explains the occurrence of the additional (002) and (004) graphitic peaks in the diffraction pattern of the studied sample and provides information about the interior structure of the dahlia-type aggregates.
Katsumi Kaneko - One of the best experts on this subject based on the ideXlab platform.
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cu phthalocyanine mediated nanowindow production on single wall carbon Nanohorn
Molecular Physics, 2021Co-Authors: Dragana Stevic, Ayumi Furuse, Fernando Vallejosburgos, Radovan Kukobat, Katsumi KanekoAbstract:We report a route for opening nanowindows on graphene wall of single wall carbon Nanohorn (SWCNH) aided by copper (II) 2,3,9,10,16,17,23,24-octakis (octyloxy)-29H, 31H-phthalocyanine (CuPc), which ...
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Facilitation of Water Penetration through Zero-Dimensional Gates on Rolled-up Graphene by Cluster–Chain–Cluster Transformations
2016Co-Authors: Tomonori Ohba, Hirofumi Kanoh, Katsumi KanekoAbstract:We demonstrate a water penetration mechanism through zero-dimensional nanogates of a single-walled carbon Nanohorn. Water vapor adsorption via the nanogates is delayed in the initial adsorption stage but then proceeds at a certain rate. The mechanism is proposed to be a water cluster–chain–cluster transformation via the nanogates. The growth of water clusters in internal nanospaces facilitates water penetration into these nanospaces, providing an intrinsic mechanism for zero-dimensional water
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Toward in silico modeling of palladium–hydrogen–carbon Nanohorn nanocomposites
Physical Chemistry Chemical Physics, 2014Co-Authors: Piotr Kowalczyk, Piotr A. Gauden, Sylwester Furmaniak, Artur P. Terzyk, Katsumi KanekoAbstract:We present the first in silico modeling of the Pd–H-single-walled carbon Nanohorn nanocomposites. Temperature-quench Monte Carlo simulations are used to generate the most stable morphologies of Pd81 clusters (cluster sizes of ∼2 nm) deposited inside the morphologically defective single-walled carbon Nanohorns (S. Furmaniak, A. P. Terzyk, K. Kaneko, P. A. Gauden, P. Kowalczyk, T. Itoh, Phys. Chem. Chem. Phys., 2013, 15, 1232–1240). The optimized Pd81-single-walled carbon Nanohorn nanocomposites are next used in calculating the H binding energy distributions at 300 K. The most stable positions of H impurity in confined Pd81 clusters are identified, showing subsurface character of H absorption from the dilute H2 gas at 300 K. The H binding energy distribution on the Pd(100) open surface at 300 K is computed and compared with those corresponding to Pd81–single-walled carbon Nanohorn nanocomposites. Finally, the impact of the Pd–H short-range order on the H binding energy is explored and critically discussed.
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surface to volume ratio of carbon Nanohorn a crucial factor in co2 ch4 mixture separation
Chemical Physics Letters, 2014Co-Authors: Sylwester Furmaniak, Piotr A. Gauden, Katsumi Kaneko, Artur P. Terzyk, Piotr Kowalczyk, Tomonori OhbaAbstract:Using the first realistic model of single walled carbon Nanohorn and molecular simulation data we show the 3D graphs relating the selectivity of CO2/CH4 separation with a surface to volume ratio of a Nanohorn, the total mixture pressure and the mole fraction of CO2 in the bulk phase. It is proved that surface to volume ratio is a crucial parameter determining the selectivity. Finally, the equation is proposed, making possible to predict the selectivity of a Nanohorn for separation of CO2/CH4 mixture.
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structural modeling of dahlia type single walled carbon Nanohorn aggregates by molecular dynamics
Journal of Physical Chemistry A, 2013Co-Authors: L. Hawelek, A Brodka, Tomonori Ohba, John C. Dore, Masako Yudasaka, Sumio Iijima, Katsumi Kaneko, Alex C. Hannon, Agata BurianAbstract:The structure of dahlia-type single-walled carbon Nanohorn aggregates has been modeled by classical molecular dynamics simulations, and the validity of the model has been verified by neutron diffraction. Computer-generated models consisted of an outer part formed from single-walled carbon Nanohorns with diameters of 20–50 A and a length of 400 A and an inner turbostratic graphite-like core with a diameter of 130 A. The diffracted intensity and the pair correlation function computed for such a constructed model are in good agreement with the neutron diffraction experimental data. The proposed turbostratic inner core explains the occurrence of the additional (002) and (004) graphitic peaks in the diffraction pattern of the studied sample and provides information about the interior structure of the dahlia-type aggregates.
Nikos Tagmatarchis - One of the best experts on this subject based on the ideXlab platform.
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Structure, Properties, Functionalization, and Applications of Carbon Nanohorns
Chemical Reviews, 2016Co-Authors: Nikolaos Karousis, Irene Suarez-martinez, Christopher P. Ewels, Nikos TagmatarchisAbstract:Carbon Nanohorns (sometimes also known as nanocones) are conical carbon nanostructures constructed from an sp2 carbon sheet. Nanohorns require no metal catalyst in their synthesis, and can be produced in industrial quantities. They provide a realistic and useful alternative to carbon nanotubes, and possibly graphene, in a wide range of applications. They also have their own unique behavior due to their specific conical morphology. However, their research and development has been slowed by several factors, notably during synthesis, they aggregate into spherical clusters ∼100 nm in diameter, blocking functionalization and treatment of individual nanocones. This limitation has recently been overcome with a new approach to separating these “dahlia-like” clusters into individual nanocones. In this review, we describe the structure, synthesis, and topology of carbon Nanohorns, and provide a detailed review of Nanohorn chemistry.
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photoinduced electron transfer on aqueous carbon Nanohorn pyrene tetrathiafulvalene architectures
Chemistry: A European Journal, 2007Co-Authors: Georgia Pagona, Atula S D Sandanayaka, Alan Maigne, George C Papavassiliou, Ioannis D Petsalakis, Barry R Steele, Masako Yudasaka, Sumio Iijima, Nikos TagmatarchisAbstract:: Water-soluble carbon-Nanohorn-tetrathiafulvalene (CNH-TTF) nanoensembles were prepared by utilizing positively charged pyrene as an assembly medium and characterized by spectroscopy and electron microscopy. Electronic interactions within the nanoensemble were probed by optical spectroscopy, indicating electron transfer between the TTF units and CNHs after light illumination.
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cover picture covalent functionalization of carbon Nanohorns with porphyrins nanohybrid formation and photoinduced electron and energy transfer adv funct mater 10 2007
Advanced Functional Materials, 2007Co-Authors: Georgia Pagona, Atula S D Sandanayaka, Nikos Tagmatarchis, Masako Yudasaka, Yasuyuki Araki, Jing Fan, Georgios Charalambidis, Athanassios G Coutsolelos, Bernard Boitrel, Sumio IijimaAbstract:A transmission electron microscopy image of the spherical superstructure of dahlia flowerlike carbon Nanohorns (CNHs), functionalized at the conical tips with porphyrins (H2P), is shown, together with an illustration of the architecture of the novel CNH–H2P nanohybrid material. Nikos Tagmatarchis, Osamu Ito, and co-workers report on the preparation and photophysical properties of this material on p. 1705. Photo-excitation of H2P with visible light results in reduction of the CNHs with a simultaneous oxidation of the porphyrin moiety, resulting in a charge-separated state; CNH•––H2P•+. The covalent attachment of carbon Nanohorns (CNHs) to α-5-(2-aminophenyl)-α-15-(2-nitrophenyl)-10,20-bis(2,4,6-trimethyl-phenyl)-porphyrin (H2P) via an amide bond is accomplished. The resulting CNH–H2P nanohybrids form a stable inklike solution. High-resolution transmission electron microscopy (HRTEM) images demonstrate that the original dahlia-flowerlike superstructure of the CNHs is preserved in the CNH–H2P nanohybrids. Steady-state and time-resolved fluorescence studies show efficient quenching of the excited singlet state of H2P, suggesting that both electron and energy transfer occur from the singlet excited state of H2P to CNHs, depending on the polarity of the solvent. In the case of electron transfer, photoexcitation of H2P results in the reduction of the Nanohorns and the simultaneous oxidation of the porphyrin unit. The formation of a charge-separated state, CNH•––H2P•+, has been corroborated with the help of an electron mediator, hexyl-viologen dication (HV2+), in polar solvents. Moreover, the charge-separated CNH•––H2P•+ states have been identified by transient absorption spectroscopy.
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covalent functionalization of carbon Nanohorns with porphyrins nanohybrid formation and photoinduced electron and energy transfer
Advanced Functional Materials, 2007Co-Authors: Georgia Pagona, Atula S D Sandanayaka, Nikos Tagmatarchis, Masako Yudasaka, Yasuyuki Araki, Jing Fan, Georgios Charalambidis, Athanassios G Coutsolelos, Bernard Boitrel, Sumio IijimaAbstract:The covalent attachment of carbon Nanohorns (CNHs) to α-5-(2-aminophenyl)-α-15-(2-nitrophenyl)-10,20-bis(2,4,6-trimethyl-phenyl)-porphyrin (H2P) via an amide bond is accomplished. The resulting CNH–H2P nanohybrids form a stable inklike solution. High-resolution transmission electron microscopy (HRTEM) images demonstrate that the original dahlia-flowerlike superstructure of the CNHs is preserved in the CNH–H2P nanohybrids. Steady-state and time-resolved fluorescence studies show efficient quenching of the excited singlet state of H2P, suggesting that both electron and energy transfer occur from the singlet excited state of H2P to CNHs, depending on the polarity of the solvent. In the case of electron transfer, photoexcitation of H2P results in the reduction of the Nanohorns and the simultaneous oxidation of the porphyrin unit. The formation of a charge-separated state, CNH•––H2P•+, has been corroborated with the help of an electron mediator, hexyl-viologen dication (HV2+), in polar solvents. Moreover, the charge-separated CNH•––H2P•+ states have been identified by transient absorption spectroscopy.
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aqueous carbon Nanohorn pyrene porphyrin nanoensembles controlling charge transfer interactions
Diamond and Related Materials, 2007Co-Authors: Georgia Pagona, Alan Maigne, Masako Yudasaka, Sumio Iijima, Nikos TagmatarchisAbstract:A combination of π-π stacking and electrostatic interactions was used to integrate an anionic porphyrin (H 2 P 2- ) with carbon Nanohorns (CNHs), mediated by positively charged pyrene (pyr + ) units. The resulting water-soluble CNHs-pyr + -H 2 P 2- nanoensemble was characterized by optical spectroscopy and electron microscopy techniques. The strong fluorescence emission of H 2 P 2- was significantly quenched by CNHs, suggesting effective energy and electron transfer between the photo-excited porphyrin and the extended π-electronic network of Nanohorns. Blank experiments validated the supramolecular concept of synergistic electrostatic interactions and signified the importance of CNHs as electron acceptors towards the preparation of some novel donor-acceptor nanosystems.
K. Takahashi - One of the best experts on this subject based on the ideXlab platform.
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direct evidence on c c single bonding in single wall carbon Nanohorn aggregates
Journal of Physical Chemistry C, 2007Co-Authors: Shigenori Utsumi, Hirofumi Kanoh, Yoshiyuki Hattori, Masako Yudasaka, Sumio Iijima, Hideki Sakai, Hiroaki Honda, K. Takahashi, Katsumi KanekoAbstract:The structure of single-wall carbon Nanohorn (SWNH) was analyzed with X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The considerably strong peak due to single bonding carbons was observed in C1s XPS spectrum of SWNH. This peak intensity increases with oxidation treatment, coinciding with the decrease in Raman G/D intensity ratio. It is concluded that the presence of a considerable amount of single bonding carbons is the reason for the unique assembly structure accompanying with a strong D-band in Raman spectrum of SWNH.
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pore structure and adsorption properties of single walled carbon Nanohorn bud like aggregates treated in different atmospheres
Physica B-condensed Matter, 2002Co-Authors: F Kokai, Elena Bekyarova, Masako Yudasaka, Sumio Iijima, Katsumi Kaneko, K. Takahashi, D KasuyaAbstract:Abstract Pore structure changes of single-walled carbon Nanohorns (SWNHs) after oxidation with O 2 and CO 2 at different temperatures were studied. Low-temperature N 2 adsorption isotherms were analyzed to evaluate the parameters of both types of porosities present: interparticle pores and intraparticle cavities. Bud -SWNHs, produced by laser ablation of carbon in He atmosphere, have completely closed intraparticles. Oxidation in O 2 at 693 K opens 77% of the closed Nanohorns.
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field emission properties of carbon Nanohorn films
Journal of Applied Physics, 2002Co-Authors: Jean-marc Bonard, F Kokai, Richard Gaál, Slaven Garaj, L Thiennga, László Forró, Masako Yudasaka, K. Takahashi, Sumio IijimaAbstract:Self-supporting carbon films were prepared from a carbonaceous material, Nanohorns. Nanohorns are spherical particles built of sharp cones of a single graphene sheet. The films show good field emission characteristics due to the sharp horn-like structures, in particular a low turn-on field and good long-term stability.
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selective production of single wall carbon Nanohorn aggregates and their formation mechanism
Journal of Physical Chemistry B, 2002Co-Authors: D Kasuya, F Kokai, Masako Yudasaka, K. Takahashi, Sumio IijimaAbstract:Single-wall carbon Nanohorn (SWNH) aggregates can be produced by CO2 laser vaporization of carbon, and a single aggregate can take either a “dahlia-like” or “bud-like” form. We found that “dahlia-l...
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molecular potential structures of heat treated single wall carbon Nanohorn assemblies
Journal of Physical Chemistry B, 2001Co-Authors: Katsumi Kaneko, D Kasuya, And M Yudasaka, Kaori Hirahara, William A. Steele, K. Takahashi, Sumio IijimaAbstract:The microporosity of the heat-treated single-wall carbon Nanohorn (SWNH) particles is characterized by nitrogen adsorption at 77 K and the molecular potential calculation using the function, which is based on the Lennard-Jones pair potential. The depth difference of the molecular potential for N2 between the SWNH intraparticle pore and the interparticle space is close to 1000 K. Although the SWNH without the heat-treatment has no open intra-Nanohorn space, the intraparticle pores open with the high-temperature treatment in O2. The heat-treatment at 693 K opens almost perfectly the intraparticle pores, leading to 0.47 mL g-1 of the micropore volume and 1010 m2 g-1 of the specific surface area. The subtraction of the N2 adsorption isotherm of the SWNH from that of the SWNH treated at 693 K gave the N2 adsorption isotherm only in the intraparticle pore spaces. The adsorption sites derived from the difference adsorption isotherm are assigned to the pores having different interaction potentials.
