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Article

Study of the Iodine Fixation over High Surface Area Graphite (HSAG-100) Under Mild Conditions

by
Angel Maroto-Valiente
,
Carla A. Blanco-Camus
,
Ana I. Mártir Bueno
,
Elena M. Mesa-Bribián
and
Jesús Alvarez-Rodríguez
*
Departamento Química Inorgánica y Química Técnica, Facultad de Ciencias (UNED), 28232 Las Rozas de Madrid, Spain
*
Author to whom correspondence should be addressed.
C 2025, 11(4), 73; https://doi.org/10.3390/c11040073
Submission received: 14 July 2025 / Revised: 24 September 2025 / Accepted: 28 September 2025 / Published: 30 September 2025
(This article belongs to the Section Carbon Materials and Carbon Allotropes)
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Abstract

The controlled incorporation of halogens into carbon materials remains a challenge, particularly under mild and scalable conditions. In this work, we investigate the fixation of iodine on high-surface-area graphite (HSAG-100) using green solvents and moderate temperatures. Commercial HSAG was treated with iodine in aqueous and in organic media, with and without promoters, and characterized by XPS, LEIS, N2 physisorption, TGA/TPD, and XRD. The results reveal that iodine contents up to ~0.6 at% can be achieved, with incorporation strongly influenced by solvent and reaction time. XPS and LEIS confirmed the presence of C–I bonds, while BET analysis showed only moderate decreases in surface area and unchanged mesopore size distribution. Thermogravimetric and TPD analyses demonstrated the high thermal stability of C–I species, and XRD patterns ruled out intercalation between graphene layers. Collectively, these findings demonstrate that iodine can be covalently anchored to HSAG under mild conditions, preserving the graphitic structure and generating stable edge functionalities, thus opening a route for the design of halogen-doped carbons for catalytic and electrochemical applications.

1. Introduction

Carbon nanotubes (CNTs) [1], carbon nanofibers (CNFs) [2], graphite [3], carbyne [4], graphynes [5] and graphene-like [6] structures attract intense research interest because their physicochemical properties benefit catalysis [7], electrocatalysis [8], thermoelectric [9], optical and optoelectrical applications [10]. Among them, high surface area graphite (HSAG) exhibits both high thermal and chemical stability and displays textural properties that are particularly suitable for catalysis, with tunable behavior related to its surface composition.
Beyond natural chemical resistance and hydrophobicity, the surface chemistry of carbon materials has attracted much attention, since it plays a crucial role both when carbons act as supports and when they function as catalysts themselves, in both liquid- and gas-phase processes. Therefore, many studies emphasize the importance of surface functional groups as participants in active sites. In this sense, most of previous studies focus on the role of the surface oxygen functional groups of carbon materials [11,12] and how the distribution and density of some of these groups could be tunable to improve the activity. Similarly, the introduction of heteroatoms into carbon materials has attracted considerable attention, either as surface groups or as dopants incorporated into the lattice. For example, sulfur surface groups [13] have been correlated with acidic active sites for catalytic applications, while nitrogen functional groups [14] have attracted great interest both as active sites and as promoters that modify the electronic environment of metallic nanoparticles. As a result, nitrogen-doped graphene has been shown to be more active than non-doped graphene in catalytic oxidation reactions [15,16], due to the enhanced electron density of N-doped sites and their stronger interaction with chemisorbed reactants and surface intermediates [17,18]. Discussions about different catalytic processes highlight that these surface atoms are key factors contributing to catalytic selectivity and/or activity and covalently doped graphitic carbons can act as polarizing agents that facilitate electrocatalytic reactions, such as the ORR process.
To advance the goal of developing alkaline-resistant catalysts with better resistance to aqueous media, largely demanded in actual bioresource valorization process, this work presents a novel series of metal-free carbon catalysts, without alkaline earth metals as active sites, together with a methodology for the synthesis and characterization of halogenated-carbon materials. An enhanced surface electronic density is expected upon halogen incorporation, as a result of the higher polarizing power derived from the electronegativity difference between iodine (2.66) and carbon (2.55), similar to the effects reported for other heteroatoms (O, S, N).
Early works on the adsorption of iodine on natural graphite [19,20] showed a transition from physisorption to chemisorption at 723 K, outgassing experiments of iodine adsorbed on graphite. The presence of surface functional groups on graphite would affect adsorption, and either distort in case of physisorption or provide additional chemical pathways for chemisorption in order to explain this behaviour. Iwamoto et al. [20] suggest that iodine is held on the edges of the basal planes but Salzano [19] argued for lamellar compounds. In fact, a graphite intercalation compound with iodine was reported by Hung et Kucera [21] from X-ray diffraction data. This discussion is still open and recent papers suggest lamellar or lateral anchorage [22,23,24,25].
Recent advances in halogen-doped carbon materials highlight their potential in diverse applications ranging from photocatalysis to sensing and adsorption. By introducing halogen-doped carbon quantum dots (CQDs) into ZnO@ZIF-8 core–shell structures, the study reveals how different halogens fine-tune pore size, band gap, and impedance, leading to enhanced gas selectivity and sensitivity [26]. Halogen doping (e.g., F, Cl, Br) has emerged as a powerful strategy to modulate the electronic structure and photoluminescence of carbon-based nanomaterials, enabling band gap tuning, enhanced chemical reactivity, and improved fluorescence performance for sensing and optoelectronic applications [27,28]. Halogen doping of graphene-based materials has emerged as an effective strategy to modulate their electronic structure and enhance their reactivity, enabling highly selective sensing applications such as Cr3+ detection [29]. Playing a central role by modifying the electronic structure and defect density of the carbon nanofibers, thereby enhancing their interaction with chlorinated pollutants and improving their efficiency in water purification [30], halogenated graphene derivatives are attractive options for use in supercapacitors [31]. Halogen doping also provides an effective strategy to tailor the electrochemical behavior of graphene derivatives. In particular, bromine incorporation enhances surface functionality, conductivity, and ion accessibility, leading to improved performance in energy storage applications [32,33] and enhanced HER activity [34]. Collectively, these findings demonstrate that halogen doping is not merely a niche modification but a versatile and increasingly strategic approach in the design of functional carbon-based materials.
Herein, we present methods to prepare iodine-doped HSAG and discuss the physicochemical characteristics of the material, with the aim of confirming iodine incorporation and determining whether it is adsorbed on the surface of HSAG, bonded as C–I at the edges of basal planes, incorporated in lamellar compounds, or intercalated between layers.

2. Experimental Methods

2.1. Materials

The initial materials used in this study were commercial high surface area graphite (TIMREX® HSAG100 from IMERYS); pure iodine beads (PANREAC); potassium iodide (SIGMA-ALDRICH); chemically pure granulated iron (PANREAC); decane (PANREAC); and bi-distilled water. The textural properties of the starting HSAG were verified by N2 physisorption at 77 K (Micromeritics ASAP 2020; degassing at 493 K for 10 h), yielding SBET = 88 ± 2 m2 g−1 and an average mesopore diameter of 3.3–3.5 nm (BJH). These values are consistent with prior reports for HSAG grades.

2.2. Iodination Procedures

The solvent was placed in a 250 mL three-neck round-bottom flask under reflux thermo-stated at 100 °C, then reagents were added sequentially in this order: I2 (0.1 g), KI (0.2 g) and Fe0 (0.1 g), and the system was covered with aluminum foil to protect it from light. The reaction time was counted from the moment HSAG (0.5 g) was added. Once the experiment had completed the required time, the flask was removed from the heat source and cooled to room temperature. Samples were filtered and washed with pure solvent until the negative iodine-test in washed solvent. Finally, samples were dried for 24 h at 90 °C and stored in the dark. Synthetized samples at 96 h reaction run time are identified in this article as IKD, IKFeD, for samples in decane, and IKW, IKFeW, for samples in water.

2.3. Characterization Methods

The crystallinity of the original and modified samples was verified by XRD diffraction patterns recorded in a PANalytical diffractometer model X’Pert MPD equipped with Cu Kα radiation (working at 40 kV, 45 mA, λ = 0.15418 nm), using a d-bound of angle (2θ) in the range of 5 to 50, with a step size 0.05° at a scanning step speed of 1 min−1.
Textural properties of the samples were studied by adsorption–desorption nitrogen isotherm measurements volumetrically at 77 K in Micromeritics ASAP 2020 equipment, using 150 mg of degassed sample under vacuum at 493 K for 10 h. Specific surface area was obtained by the Brunauer–Emmett–Teller (BET) method, while pore size distribution and pore volume were derived from the t-plot and BJH methods.
Thermogravimetric analyses (TGAs) were performed in a SDTQ600 5200 TA System. About 15 mg of sample was treated at room temperature for 30 min under helium (100 mL/min) for purging. Then, the system was heated up to 1273 K using a rate of 10 K/min.
X-ray photoelectron spectra were recorded with an Omicron spectrometer equipped with a SPECS PHOIBOS 100 MCD detector and non-monochromatic Mg Kα (hv = 1256.6 eV) X-ray radiation operating at 200 W (12 kV). The samples were pressed into a small thin pellet of 15 mm diameter and then mounted on the sample holder and introduced into the chamber where they were degassed for 6–8 h, to achieve a dynamic vacuum below 10−8 Pa prior to analysis. The probing depth of the XPS measurements was estimated from the inelastic mean free path (IMFP, λ) of photoelectrons, which depends on their kinetic energy. Using Mg Kα radiation (hν = 1256.6 eV), the kinetic energies of the C 1s (~972 eV) and I 3d (~637 eV) photoelectrons correspond to λ values of approximately 1.5–2.5 nm. Taking three times λ as the effective information depth, the analyzed surface region extends to about 5–7 nm. This estimation, in line with accepted values for carbon-based materials [35], highlights the surface sensitivity of our XPS analysis. Spectra were analyzed with CasaXPS (v2.3.24) using RSF sensitivity factors, Shirley background subtraction, and peak fitting.
Low-energy ion scattering (LEIS) measurements were carried out with an Omicron spectrometer equipped with a SPECS PHOIBOS 100 MCD detector and an Omicron ISE 100 Fine Focus ion source, using He+ ions as primary source with kinetic energy of 2 keV at He backpressure of 2.5 × 10−6 mbar and a scattering angle of 90º. The kinetic energy (E) of backscattered ions was calculated according to elastic binary collision kinematics [36].

3. Results

The composition of the samples was evaluated from the XPS survey spectra (Figure 1). This surface chemical analysis revealed the elemental distribution of carbon, oxygen, iodine, potassium, and iron, quantified using CasaXPS v. 2.3.24 software. All samples contained carbon (>90 at.%) and oxygen as main components, as expected for this type of carbon material. In pristine HSAG, only C and O (≈2.5 at.%) were detected. HSAG samples treated with iodine registered measurable iodine contents, higher in those prepared in decane with (IKFeD) and without iron (IKD) (~0.6 at%) than in those prepared in water with (IKFeW) and without iron (IKW) (~0.1 at%).
Table 1 summarizes the main XPS results. The O/C ratio remained essentially constant (≈0.02) for HSAG treated in decane but was higher in samples prepared in water (IKFeW ≈ 0.16). The I/O and I/C ratios were about one order of magnitude higher in de-cane-treated samples (≈0.1) than in water-treated samples (≈0.01).
The deconvolution of the C 1s region (Figure 1) was performed by separating the main sp2 graphitic contribution from oxygenated and iodinated components. Following previous studies on graphite (0001), the sp2 peak was modeled as a highly symmetrical component [37]. This tailing is characteristic of extended π-conjugated domains in semi-metallic carbons. In contrast, the contributions from C–O, C–I and C–K environments were fitted with symmetric Gaussian–Lorentzian (GL) functions, consistent with their localized bonding nature. In functionalized carbons, the asymmetry of the sp2 peak may be partially suppressed or masked by defect and heteroatom-related states; therefore, the use of DS for the sp2 component was restricted to reflect the degree of graphitic ordering while maintaining physical consistency in the overall fit. Iodine was clearly detected in the I 3d region (615–635 eV BE) by XPS (Figure 2). A time-dependent study (0.5, 2, 24, 72, and 96 h) showed a progressive increase in iodine incorporation for IKD, IKFeD, and IKFeW with the increase of iodation time. Regarding the iodine species, the I 3d5/2 peak at 620.3 eV was assigned to C–I bonds [38,39], distinct from the signal of K–I at 619.1 eV.
Additional samples treated under Helium flow at 773 K and 1273 K after iodination retained iodine at 773 K but not at 1273 K, indicating thermal desorption at higher temperatures.
The effectiveness of the halogenation process evidenced by XPS was further confirmed by LEIS on the outermost surface of HSAG. Figure 3 compares samples prepared in decane and water with KI and pristine HSAG. The presence of iodine in the outermost surface layer of iodinated graphite was confirmed by the signal at 1800 eV kinetic energy. The very low intensity observed in the LEIS spectra is attributed to resonant neutralization of positive helium ions upon scattering from the HSAG surface [40,41].
The nitrogen adsorption isotherm of HSAG-100 displayed type IV behavior with an H3 hysteresis loop, indicative of meso-porosity without a well-defined structure. The BET surface area was ~88 m2 g−1 (Figure 4). This type of hysteresis loop is characteristic of lamellar graphite and was identical for all samples, showing neither expansion of the laminar spacing nor pore collapse, as typically observed during oxidation. The Barrett–Joyner–Halenda (BJH) pore size distribution, derived from the desorption branch of the isotherm, revealed a broad distribution of mesopores centered at ~3.5 nm (Figure 4). These surface area values are consistent with previous reports for HSAG-100 [42].
Adsorption measurements at 77 K demonstrated that iodine incorporation caused a moderate decrease in BET surface area to ~50 m2 g−1, without significant change in the mesopore size distribution (~3.3 nm) (Table 1).
Figure 5 and Figure 6 show the thermogravimetric analysis (TGA) results of graphite samples treated with iodine in an inert atmosphere. All samples exhibited high thermal stability under helium (Figure 5). Pristine HSAG was more stable than the iodinated samples. Those prepared in decane solution showed greater weight loss than those prepared in water. The differential TGA (DTGA) revealed broad peaks for IKD and IKFeD, and a sharp peak for IKFeW. There is a significant weight loss (15–40%) that starts at around 873 K.
Analysis of the effluent gases during temperature program desorption (TPD) under helium flow by mass spectroscopy (MS) confirmed the stability of the graphite samples (Figure 6). No desorption of physisorbed iodine or labile surface groups was observed below 773 K. At higher temperatures, decomposition products included mainly CO (m/z = 28), which can be attributed to ether and/or quinone surface groups [43].
X-ray diffraction (XRD) confirmed the structural order of HSAG-100 and iodinated samples. As shown in Figure 7, the main reflection at 26.5° (2θ), corresponding to the (002) plane, remained unchanged for all samples. This demonstrates that the materials retained a highly ordered graphitic structure, with an interlayer spacing of ~0.334 nm (d002), consistent with reported values [24]. The absence of any shift in the (002) reflection indicates that iodine was not intercalated between the graphene layers.

4. Discussion

XPS and LEIS analyses confirmed the presence of iodine in HSAG treated under mild conditions. In both sets of experiments, the evolution of the I/C ratio with reaction time demonstrated a progressive increase in iodine incorporation, which was accompanied by a concomitant increase in the I/O ratio. This trend suggests a partial displacement of oxygen-containing groups by iodine atoms. The amount of iodine incorporated by this method (~0.6–0.7 at% ≈ 5–6 mg g−1) is significantly higher than that previously reported (0.48 mg g−1) [20]. In all cases, the O/C ratio was higher than in pristine HSAG-100, particularly in the samples prepared in water, which exhibited more surface oxidation compared to those treated in decane.
The presence of iodine atoms in HSAG can, in principle, originate from adsorbed species, intercalated compounds, or covalently grafted functionalities. However, the combined evidence from BET, TGA, TPD, and XRD strongly supports the predominance of covalently grafted C–I bonds at edge sites.
Nitrogen adsorption–desorption isotherms (SBET) showed a reduction in surface area in iodinated samples compared to pristine HSAG, while pore size distribution and hysteresis loop type remained unchanged. This indicates that iodine fixation does not collapse or enlarge the lamellar pore structure but rather hinders the adsorption of N2 molecules, consistent with the interpretation proposed by Iwamoto [20], who attributed this effect to C–I bonds located at the edges of basal planes.
XRD patterns further corroborate this conclusion: the main diffraction peak at 26.5° (2θ), corresponding to the (002) plane, remained unchanged across all samples, with an interplanar spacing of 3.35 Å. This result demonstrates that the HSAG-100 structure remains stable under iodine treatment, and excludes laminar intercalation as reported for iodine–graphite intercalation compounds by Hung [21].
Thermogravimetric analyses (TGA) provide complementary evidence. No low-temperature weight loss (<573 K) was observed, excluding the presence of physisorbed iodine. Likewise, no peaks were detected in the medium-temperature range (400–900 K), which is typically associated with decomposition of labile oxygenated groups, indicating that surface degradation during iodination was minimal [39]. Instead, the weight losses detected occurred at high temperature (≥873 K), corresponding to the decomposition of highly stable species. These include ether and/or quinone groups, as also evidenced in TPD-MS [39], and covalently bound C–I species.
To validate this interpretation, samples were analyzed by XPS after thermal treatment under helium flow at 773 K and 1273 K. After heating to 773 K, the I 3d peak at 620.3 eV (assigned to C–I bonds [39,44]) was still detected, confirming the thermal stability of covalent iodine species. However, after heating to 1273 K, iodine signals disappeared from the XPS survey, indicating complete loss of C–I functionalities.
Taken together, these results demonstrate that iodine is not intercalated nor physiosorbed but covalently incorporated into HSAG as C–I bonds at the edge sites of basal planes. This incorporation preserves the graphitic structure, induces only moderate textural changes, and provides thermally stable functional groups, thus confirming the effective halogenation of HSAG under mild conditions.

5. Conclusions

The incorporation of iodine into high-surface-area graphite (HSAG) under mild conditions was successfully demonstrated. The synthesis of iodinated graphite was found to strongly depend on both reaction time and solvent properties. Samples obtained after 30 min, 2 h, 24 h, 72 h, and 96 h in aqueous solution contained significantly less iodine than those synthesized in decane.
XRD patterns showed no shift of the graphitic (002) diffraction peak, indicating that the crystalline structure of HSAG remained intact and that iodine incorporation does not occur via laminar intercalation. BET analysis revealed a reduction in surface area for iodinated HSAG compared to pristine HSAG, while pore volume and pore size distribution remained unchanged. These results are consistent with iodine being covalently bonded as C–I at the edges of basal planes.
Thermogravimetric (TGA) and temperature-programmed desorption (TPD) analyses confirmed the absence of physisorbed iodine in HSAG-I samples. Instead, the observed weight loss at high temperature was associated with the decomposition of stable functional groups, supporting the formation of covalent C–I bonds.
Finally, XPS and LEIS provided direct evidence of iodine fixation on the outermost surface of HSAG, confirming the effectiveness of the halogenation process under mild conditions. Collectively, the combined structural, textural, and spectroscopic analyses demonstrate that iodine is incorporated as stable C–I functionalities at edge sites, without disrupting the graphitic lattice, thereby establishing an effective route for the preparation of iodine-doped carbon materials.
Collectively, these findings demonstrate that iodine can be covalently anchored into HSAG without disrupting the graphitic lattice, thereby generating stable edge functiona-lities. Such iodinated carbons represent promising precursors for metal-free catalysts in alkaline aqueous media, as well as potential support for nanoparticles and functional materials for sensing and adsorption applications. Future studies will explore their performance in these contexts, further extending the utility of halogen-doped carbons in catalytic and electrochemical systems.

Author Contributions

Conceptualization, J.A.-R.; methodology, J.A.-R. and A.M.-V.; validation, A.M.-V.; investigation, A.I.M.B., C.A.B.-C. and E.M.M.-B.; resources, J.A.-R. and A.M.-V.; data curation, A.I.M.B., C.A.B.-C. and A.M.-V.; writing—review and editing, A.I.M.B., C.A.B.-C., E.M.M.-B., J.A.-R. and A.M.-V.; supervision, J.A.-R. and A.M.-V.; funding acquisition, J.A.-R. and A.M.-V. All authors have read and agreed to the published version of the manuscript.

Funding

The authors acknowledge financial support from Ministerio de Ciencia e Innovación (Spain): project TED 2021-131914B-I00 funded by the European Union—NextGenerationEU/PRTR.

Data Availability Statement

The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Zheng, M.; Chi, Y.; Hu, Q.; Tang, H.; Jiang, X.; Zhang, L.; Zhang, S.; Pang, H.; Xu, Q. Carbon nanotube-based materials for lithium–sulfur batteries. J. Mater. Chem. A 2019, 7, 17204–17241. [Google Scholar] [CrossRef]
  2. Peng, X.W.; Wu, K.Z.; Hu, Y.J.; Zhuo, H.; Chen, Z.H.; Jing, S.S.; Liu, Q.Z.; Liu, C.F.; Zhong, L.X. A mechanically strong and sensitive CNT/rGO–CNF carbon aerogel for piezoresistive sensors. J. Mater. Chem. A 2018, 6, 23550–23559. [Google Scholar] [CrossRef]
  3. Soria-Sánchez, M.; Maroto-Valiente, A.; Álvarez-Rodríguez, J.; Muñoz-Andrés, V.; Rodríguez-Ramos, I.; Guerrero-Ruíz, A. Carbon nanostrutured materials as direct catalysts for phenol oxidation in aqueous phase. Appl. Catal. B Environ. 2011, 104, 101–109. [Google Scholar] [CrossRef]
  4. Brzhezinskaya, M.; Zhivulin, V.E. Controlled modification of polyvinylidene fluoride as a way for carbyne synthesis. Polym. Degrad. Stab. 2022, 203, 110054. [Google Scholar] [CrossRef]
  5. Belenkov, E.; Brzhezinskaya, M.; Mavrinskii, V. Chapter 4 Graphynes: Advanced carbon materials with layered structure. In Handbook on the Graphene; Wiley-Scrivener: Beverly, MA, USA, 2019; ISBN 9781119468455. [Google Scholar]
  6. Carvalho, A.F.; Kulyk, B.; Fernandes, A.J.S.; Fortunato, E.; Costa, F.M. A Review on the Applications of Graphene in Mechanical Transduction. Adv. Mater. 2022, 34, 2101326. [Google Scholar] [CrossRef] [PubMed]
  7. Gerber, I.C.; Serp, P. A theory/experience description of support effects in carbon-supported catalysts. Chem. Rev. 2020, 120, 1250–1349. [Google Scholar] [CrossRef]
  8. Xing, Z.; Ju, Z.; Zhao, Y.; Wan, J.; Zhu, Y.; Qiang, Y. One-pot hydrothermal synthesis of Nitrogen-doped graphene as high-performance anode materials for lithium ion batteries. Sci. Rep. 2016, 6, 26146. [Google Scholar] [CrossRef] [PubMed]
  9. Blackburn, J.L.; Ferguson, A.J.; Cho, C.; Grunlan, J.C. Carbon Nanotube-Based Thermoelectric Materials and Devices. Adv Mater 2018, 30, 1704386. [Google Scholar] [CrossRef] [PubMed]
  10. Chang, H.; Wu, H. Graphene-Based Nanomaterials: Synthesis, Properties, and Optical and Optoelectronic Applications. Adv. Funct. Mater. 2013, 23, 1984–1997. [Google Scholar] [CrossRef]
  11. Zhao, H.; Ye, J.; Song, W.; Zhao, D.; Kang, M.; Shen, H.; Li, Z. Insights into the Surface Oxygen Functional Group-Driven Fast and Stable Sodium Adsorption on Carbon. ACS Appl. Mater. Interfaces 2020, 12, 6991–7000. [Google Scholar] [CrossRef]
  12. Soria-Sánchez, M.; Maroto-Valiente, A.; Álvarez-Rodríguez, J.; Rodríguez-Ramos, I.; Guerrero-Ruíz, A. Efficient catalytic wet oxidation of phenol using iron acetylacetonate complexes anchored on carbon nanofibers. Carbon 2009, 47, 2095–2102. [Google Scholar]
  13. Cuervo, M.R.; Asedegbega-Nieto, E.; Diaz, E.; Ordoñez, S.; Vega, A.; Dongil, A.B. Modification of the adsorption properties of high surface area graphites by oxygen functional groups. Carbon 2008, 46, 2096–2106. [Google Scholar] [CrossRef]
  14. Landwehr, J.; Steldinger, H.; Etzold, B.J.M. Introducing sulphur surface groups in microporous carbons. Catal. Today 2018, 301, 191–195. [Google Scholar] [CrossRef]
  15. Roldán, L.; Truong-Phuoc, L.; Ansón-Casaos, A.; Pham-Huu, C.; García-Bordejé, E. Mesoporous carbon doped with N,S heteroatoms prepared by one-pot auto-assembly of molecular precursor for electrocatalytic hydrogen peroxide synthesis. Catal. Today 2018, 301, 2–10. [Google Scholar]
  16. Gao, Y.; Hu, G.; Zhong, J.; Shi, Z.; Zhu, Y.; Su, D.S.; Ma, D. Nitrogen-Doped sp2-Hybridized Carbon as a Superior Catalyst for Selective Oxidation. Angew. Chem. Int. Ed. 2013, 52, 2109–2113. [Google Scholar]
  17. García-García, F.R.; Álvarez-Rodríguez, J.; Rodríguez-Ramos, I.; Guerrero-Ruiz, A. The use of carbon nanotubes with and without nitrogen doping as support for ruthenium catalysts in the ammonia decomposition reaction. Carbon 2010, 48, 267–276. [Google Scholar] [CrossRef]
  18. Cao, Y.; Mao, S.; Li, M.; Chen, Y.; Wang, Y. Metal/porous carbon composites for heterogeneous catalysis: Old catalysts with improved performance promoted by N-doping. ACS Catal. 2017, 7, 8090–8112. [Google Scholar] [CrossRef]
  19. Salzano, F.J. The behavior of iodine in graphite. Carbon 1964, 2, 73–81. [Google Scholar] [CrossRef]
  20. Iwamoto, K.; Oishi, J. The behavior of iodine in adsorption and desorption by graphite. J. Nucl. Sci. Technol. 1968, 5, 437–446. [Google Scholar] [CrossRef]
  21. Hung, C.C.; Kucera, D. Graphite intercalation compound with iodine as the major intercalate. Carbon 1994, 32, 1441–1448. [Google Scholar] [CrossRef]
  22. Walton, K.L.; Ghosh, T.; Viswanath, D.; Loyalka, S.; Tompson, R. Adsorption of iodine on graphite in High Temperature Gas-Cooled Reactor systems: A review. Prog. Nucl. Energy 2014, 73, 21–50. [Google Scholar] [CrossRef]
  23. Zhou, J.; Hao, S.; Gao, L.; Zhang, Y. Study on adsorption performance of coal based activated carbon to radioactive iodine and stable iodine. Ann. Nucl. Energy 2014, 72, 237–241. [Google Scholar] [CrossRef]
  24. Barpanda, P.; Djellab, K.; Sadangi, R.K.; Sahu, A.K.; Roy, D.; Sun, K. Structural and electrochemical modification of graphitic carbons by vapor-phase iodine-incorporation. Carbon 2010, 48, 4178–4189. [Google Scholar] [CrossRef]
  25. Li, X.; Liu, X.; Lin, C.; Qi, C.; Zhang, H.; Ma, J. Enhanced activation of periodate by iodine-doped granular activated carbon for organic contaminant degradation. Chemosphere 2017, 181, 609–618. [Google Scholar] [CrossRef]
  26. Wang, J.; Li, J.; Leng, X.; Ouyang, F. Halogen-doped CQDs as a modulation of fractional function sensing in ZIF composites. Chem. Eng. J. 2024, 493, 152874. [Google Scholar] [CrossRef]
  27. Khammat, M.A.; Khudhair, A.M.; Shwayyea, N.B. Tailoring electronic; optical, and reactive properties of Br- and F-doped graphene nanoflakes: A DFT-based study. Mater. Today Quantum 2025, 7, 100048. [Google Scholar] [CrossRef]
  28. Sethulekshmi, A.S.; Aparna, A.; Parvathi, P.; Pathak, R.; Punetha, V.D.; Selvaraj, M.; Saritha, A. Advances in doped carbon quantum dots: Synthesis, mechanisms, and applications in sensing technologies. Chem. Eng. J. 2025, 514, 163262. [Google Scholar] [CrossRef]
  29. Sujitha, S.D.A.; Rex, K.G.R.; Priya, C.; Mageswari, A.; Santhamoorthy, M.; Ramesh, P. Hybrid Material of Salen Moieties Functionalized 2D-Iodinated GO: A Fluorescent Chemosensor for Cr3+ Ion Detection. Luminiscence 2025, 40, e70228. [Google Scholar] [CrossRef]
  30. Šimek, P.; Klímová, K.; Sedmidubský, D.; Jankovský, O. Martin Pumera and Zdeněk Sofer. Towards graphene iodide: Iodination of graphite oxide. Nanoscale 2015, 7, 261. [Google Scholar] [CrossRef]
  31. Kalicharan, A.; Pitchaimani, J.; Kanna, C.B.; Rajesh, V.; Tamtam, M.R.; Koutavarapu, R.; Shakila, P.B.; Ramesh, P. Green Chemistry Approach for One-Step Synthesis of Iodinated Graphene Material for Supercapacitor Applications. ChemistrySelect 2024, 9, e202400820. [Google Scholar] [CrossRef]
  32. Jemina, I.; Mani, N.; Ramesh, P.; Sudha, N. Brominated graphene oxide: A novel synthesis approach for enhanced performance in energy storage applications. Diam. Relat. Mater. 2025, 154, 112135. [Google Scholar] [CrossRef]
  33. Rabchinskii, M.K.; Sysoev, V.V.; Ryzhkov, S.A.; Eliseyev, I.A.; Stolyarova, D.Y.; Antonov, G.A.; Struchkov, N.S.; Brzhezinskaya, M.; Kirilenko, D.A.; Pavlov, S.I.; et al. A Blueprint for the Synthesis and Characterization of Thiolated Graphene. Nanomaterials 2022, 12, 45. [Google Scholar] [CrossRef] [PubMed]
  34. Chu, K.; Wang, F.; Zhao, X.-L.; Wei, X.-P.; Wang, X.-W.; Tian, Y. One-step and low-temperature synthesis of iodine-doped graphene and its multifunctional applications for hydrogen evolution reaction and electrochemical sensing. Electrochim. Acta 2017, 246, 1155–1162. [Google Scholar] [CrossRef]
  35. Chen, J.G. NEXAFS investigations of transition metal oxides, nitrides, carbides, sulfides and other interstitial compounds. Surf. Sci. Rep. 1997, 30, 1–152. [Google Scholar] [CrossRef]
  36. Niehus, H.; Heiland, W.; Taglauer, E. Low-energy ion scattering at surfaces. Surf. Sci. Rep. 1993, 17, 213–303. [Google Scholar] [CrossRef]
  37. Lizzit, S.; Petaccia, L.; Goldoni, A. C 1s photoemission spectrum in graphite(0001). Phys. Rev. B 2007, 76, 153408. [Google Scholar] [CrossRef]
  38. Kalita, G.; Wakita, K.; Takahashi, M.; Umeno, M. Iodine doping in solid precursor-based CVD growth graphene film. J. Mater. Chem. 2011, 21, 15209–15213. [Google Scholar] [CrossRef]
  39. Coleman, K.S.; Chakraborty, A.K.; Bailey, S.R.; Sloan, J.; Alexander, M. Iodination of Single-Walled Carbon Nanotubes. Chem. Mater. 2007, 19, 1076–1081. [Google Scholar] [CrossRef]
  40. Iglesias-García, A.; García, E.A.; Goldberg, E.C. Role of He excited configurations in the neutralization of He+ ions colliding with a HOPG surface. Phys. Rev. B-Condens. Matter Mater. Phys. 2013, 87, 075434. [Google Scholar]
  41. van den Oetelaar, L.C.A.; Mikhailov, S.N.; Brongersma, H.H. Mechanism of neutralization in low-energy He+ ion scattering from carbidic and graphitic carbon species on rhenium. Nucl. Inst. Methods Phys. Res. B 1994, 85, 420–423. [Google Scholar]
  42. Tamargo-Martínez, K.; Villar-Rodil, S.; Martínez-Alonso, A.; Tascón, J.M.D. Surface modification of high-surface area graphites by oxygen plasma treatments. Appl. Surf. Sci. 2022, 575, 151675. [Google Scholar] [CrossRef]
  43. Figueiredo, J.L.; Pereira, M.F.R.; Freitas, M.M.A.; Órfão, J.J.M. Modification of the surface chemistry of activated carbons. Carbon 1999, 37, 1379–1389. [Google Scholar] [CrossRef]
  44. Krishnan, C.; Selvarajan, P.; Freeda, T.H.; Mahadevan, C.K. Growth and characterization of pure and potassium iodide-doped zinc tris-thiourea sulphate (ZTS) single crystals. Phys. B Condens. Matter 2009, 404, 289–294. [Google Scholar] [CrossRef]
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Figure 1. Survey XPS spectra of pristine and iodinated HSAG samples with core-level signals assigned (C 1s, O 1s, I 3d, Fe 2p) and C 1s region deconvoluted for every sample.
Figure 1. Survey XPS spectra of pristine and iodinated HSAG samples with core-level signals assigned (C 1s, O 1s, I 3d, Fe 2p) and C 1s region deconvoluted for every sample.
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Figure 2. High-resolution I 3d XPS spectra for: IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line) samples synthetized at 0.5, 2, 24, 72 and 96 h.
Figure 2. High-resolution I 3d XPS spectra for: IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line) samples synthetized at 0.5, 2, 24, 72 and 96 h.
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Figure 3. LEIS of HSAG-Iodinated samples (IKW, red line, and IKD, green line) compared to potassium iodide (light blue line) and HSAG (black line) untreated sample.
Figure 3. LEIS of HSAG-Iodinated samples (IKW, red line, and IKD, green line) compared to potassium iodide (light blue line) and HSAG (black line) untreated sample.
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Figure 4. N2 adsorption–desorption isotherms HSAG (77 K) of HSAG (black line), IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line) samples.
Figure 4. N2 adsorption–desorption isotherms HSAG (77 K) of HSAG (black line), IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line) samples.
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Figure 5. TGA of HSAG (black line) and HSAG-Iodinated samples: IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line).
Figure 5. TGA of HSAG (black line) and HSAG-Iodinated samples: IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line).
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Figure 6. TPD-MS of HSAG-Iodinated samples (IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line)) synthetized at 96 h reaction run time: CO (dashed line) and CO2 (solid line) evolution profile spectra.
Figure 6. TPD-MS of HSAG-Iodinated samples (IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line)) synthetized at 96 h reaction run time: CO (dashed line) and CO2 (solid line) evolution profile spectra.
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Figure 7. XRD patterns of HSAG (black line) and HSAG-Iodinated samples: IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line); synthetized at 96 h reaction run time.
Figure 7. XRD patterns of HSAG (black line) and HSAG-Iodinated samples: IKD (red line), IKFeD (green line), IKW (dark blue line) and IKFeW (light blue line); synthetized at 96 h reaction run time.
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Table 1. Composition ratio, surface area and mode pore distribution of parent and treated graphite after 96 h reaction runtime.
Table 1. Composition ratio, surface area and mode pore distribution of parent and treated graphite after 96 h reaction runtime.
IDSBET (m2 g−1)dBJH (nm) C1s (%at)O1s (%at)I3d (%at)Fe2p (%at)K2s (%at)
HSAG883.397.602.40n.d.n.d.n.d.
IKD483.396.262.790.63n.d.0.32
IKFeD493.296.322.590.600.060.43
IKW613.495.554.420.03n.d.n.d.
IKFeW453.491.557.480.030.94n.d.
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Maroto-Valiente, A.; Blanco-Camus, C.A.; Mártir Bueno, A.I.; Mesa-Bribián, E.M.; Alvarez-Rodríguez, J. Study of the Iodine Fixation over High Surface Area Graphite (HSAG-100) Under Mild Conditions. C 2025, 11, 73. https://doi.org/10.3390/c11040073

AMA Style

Maroto-Valiente A, Blanco-Camus CA, Mártir Bueno AI, Mesa-Bribián EM, Alvarez-Rodríguez J. Study of the Iodine Fixation over High Surface Area Graphite (HSAG-100) Under Mild Conditions. C. 2025; 11(4):73. https://doi.org/10.3390/c11040073

Chicago/Turabian Style

Maroto-Valiente, Angel, Carla A. Blanco-Camus, Ana I. Mártir Bueno, Elena M. Mesa-Bribián, and Jesús Alvarez-Rodríguez. 2025. "Study of the Iodine Fixation over High Surface Area Graphite (HSAG-100) Under Mild Conditions" C 11, no. 4: 73. https://doi.org/10.3390/c11040073

APA Style

Maroto-Valiente, A., Blanco-Camus, C. A., Mártir Bueno, A. I., Mesa-Bribián, E. M., & Alvarez-Rodríguez, J. (2025). Study of the Iodine Fixation over High Surface Area Graphite (HSAG-100) Under Mild Conditions. C, 11(4), 73. https://doi.org/10.3390/c11040073

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