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Hong LF, Guo RT, Yuan Y, Ji XY, Lin ZD, Yin XF, Pan WG. 2D Ti3C2 decorated Z-scheme BiOIO3/g-C3N4 heterojunction for the enhanced photocatalytic CO2 reduction activity under visible light. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128358] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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2
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Magnetic Resonance Studies of Hybrid Nanocomposites Containing Nanocrystalline TiO2 and Graphene-Related Materials. MATERIALS 2022; 15:ma15062244. [PMID: 35329696 PMCID: PMC8949220 DOI: 10.3390/ma15062244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/09/2022] [Accepted: 03/16/2022] [Indexed: 02/01/2023]
Abstract
Nanocomposites based on nanocrystalline titania modified with graphene-related materials (reduced and oxidized form of graphene) showed the existence of magnetic agglomerates. All parameters of magnetic resonance spectra strongly depended on the materials’ modification processes. The reduction of graphene oxide significantly increased the number of magnetic moments, which caused crucial changes in the reorientation and relaxation processes. At room temperature, a wide resonance line dominated for all nanocomposites studied and in some cases, a narrow resonance line derived from the conduction electrons. Some nanocomposites (samples of titania modified with graphene oxide, prepared with the addition of water or butan-1-ol) showed a single domain magnetic (ferromagnetic) arrangement, and others (samples of titania modified with reduced graphene oxide) exhibited magnetic anisotropy. In addition, the spectra of EPR from free radicals were observed for all samples at the temperature of 4 K. The magnetic resonance imaging methods enable the capturing of even a small number of localized magnetic moments, which significantly affects the physicochemical properties of the materials.
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Rengifo-Herrera JA, Osorio-Vargas P, Pulgarin C. A critical review on N-modified TiO 2 limits to treat chemical and biological contaminants in water. Evidence that enhanced visible light absorption does not lead to higher degradation rates under whole solar light. JOURNAL OF HAZARDOUS MATERIALS 2022; 425:127979. [PMID: 34883373 DOI: 10.1016/j.jhazmat.2021.127979] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/19/2021] [Accepted: 11/30/2021] [Indexed: 05/27/2023]
Abstract
Intensive research has been focused on the synthesis of N-modified TiO2 materials having visible light absorption in order to get higher solar photocatalytic degradation rates of pollutants in water. However, an exhaustive revision of the topic underlines several controversial issues related to N-modified TiO2 materials; these issues concern (a) the methodology used for preparation, (b) the assessment of the structural characteristics, (c) the mechanistic action modes and (d) the raisons argued to explain the limited performances of the prepared materials for organic and biological targets photodegradation in water. Taking advantage of last year's progress in analytical chemistry and in material characterization methods, the authors show, for example, that some works in the literature controversially attribute the term nitrogen doping without enough analytical evidence. Additionally, some papers describe N-modified TiO2 photocatalysts as being able to generate holes with enough oxidative potential to form hydroxyl radicals under visible light. This last assertion often derives from a no pertinent use of illumination sources, light filters, or targets or a limited understanding of the thermodynamic aspects of the studied systems. None of N-containing materials prepared by herein presented methods leads, under solar light, to a significant enhancement in pollutants degradation and microorganism's inactivation kinetics.
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Affiliation(s)
- Julián A Rengifo-Herrera
- Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco" (CINDECA) (CCT-La Plata CONICET, UNLP, CICPBA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de la Plata, 47No. 257, 1900 La Plata, Argentina.
| | - Paula Osorio-Vargas
- Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco" (CINDECA) (CCT-La Plata CONICET, UNLP, CICPBA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de la Plata, 47No. 257, 1900 La Plata, Argentina; Laboratory of Thermal and Catalytic Processes (LPTC-UBB), Universidad del Bío-Bío, Facultad de Inngeniería, Departamento Ingeniería en Maderas, Concepción, Chile
| | - C Pulgarin
- School of Basic Sciences (SB), Institute of Chemical Science and Engineering (ISIC), École Polytechnique Fédérale de Lausanne (EPFL), Station 6, CH-1015, Lausanne, Switzerland; Grupo de Investigación en Remediación Ambiental y Biocatálisis (GIRAB), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia; Colombian Academy of Exact, Physical and Natural Sciences, Carrera 28A No. 39A-63, Bogotá, Colombia.
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1,4-Benzoquinone and 1,4-hydroquinone based determination of electron and superoxide radical formed in heterogeneous photocatalytic systems. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2020.113057] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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6
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Guo X, Wen C, Xu Q, Ruan C, Shen XC, Liang H. A full-spectrum responsive B-TiO2@SiO2–HA nanotheranostic system for NIR-II photoacoustic imaging-guided cancer phototherapy. J Mater Chem B 2021; 9:2042-2053. [DOI: 10.1039/d0tb02952a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A full-spectrum responsive B-TiO2@SiO2–HA nanotheranostic system has been successfully fabricated for second near-infrared photoacoustic imaging-guided synergistic cancer targeting phototherapy.
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Affiliation(s)
- Xiaolu Guo
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- College of Chemistry and Pharmaceutical Science
- Guangxi Normal University
- Guilin
- P. R. China
| | - Changchun Wen
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- College of Chemistry and Pharmaceutical Science
- Guangxi Normal University
- Guilin
- P. R. China
| | - Qianxin Xu
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- College of Chemistry and Pharmaceutical Science
- Guangxi Normal University
- Guilin
- P. R. China
| | - Changping Ruan
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- College of Chemistry and Pharmaceutical Science
- Guangxi Normal University
- Guilin
- P. R. China
| | - Xing-Can Shen
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- College of Chemistry and Pharmaceutical Science
- Guangxi Normal University
- Guilin
- P. R. China
| | - Hong Liang
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- College of Chemistry and Pharmaceutical Science
- Guangxi Normal University
- Guilin
- P. R. China
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7
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Photocatalytic H2 Evolution, CO2 Reduction, and NOx Oxidation by Highly Exfoliated g-C3N4. Catalysts 2020. [DOI: 10.3390/catal10101147] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
g-C3N4, with specific surface area up to 513 m2/g, was prepared via three successive thermal treatments at 550 °C in air with gradual precursor mass decrease. The obtained bulk and exfoliated (1ex, 2ex and 3ex) g-C3N4 were characterized and tested as photocatalysts for H2 production, CO2 reduction and NOx oxidation. The exfoliated samples demonstrated graphene-like morphology with detached (2ex) and sponge-like framework (3ex) of layers. The surface area increased drastically from 20 m2/g (bulk) to 513 m2/g (3ex). The band gap (Eg) increased gradually from 2.70 to 3.04 eV. Superoxide radicals (·O2−) were mainly formed under UV and visible light. In comparison to the bulk, the exfoliated g-C3N4 demonstrated significant increase in H2 evolution (~6 times), CO2 reduction (~3 times) and NOx oxidation (~4 times) under UV light. Despite the Eg widening, the photocatalytic performance of the exfoliated g-C3N4 under visible light was improved too. The results were related to the large surface area and low e−-h+ recombination. The highly exfoliated g-C3N4 demonstrated selectivity towards H2 evolution reactions.
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Baudys M, Paušová Š, Praus P, Brezová V, Dvoranová D, Barbieriková Z, Krýsa J. Graphitic Carbon Nitride for Photocatalytic Air Treatment. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E3038. [PMID: 32645966 PMCID: PMC7372426 DOI: 10.3390/ma13133038] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/17/2020] [Accepted: 06/29/2020] [Indexed: 11/25/2022]
Abstract
Graphitic carbon nitride (g-C3N4) is a conjugated polymer, which recently drew a lot of attention as a metal-free and UV and visible light responsive photocatalyst in the field of solar energy conversion and environmental remediation. This is due to its appealing electronic band structure, high physicochemical stability and earth-abundant nature. In the present work, bulk g-C3N4 was synthesized by thermal decomposition of melamine. This material was further exfoliated by thermal treatment. S-doped samples were prepared from thiourea or further treatment of exfoliated g-C3N4 by mesylchloride. Synthesized materials were applied for photocatalytic removal of air pollutants (acetaldehyde and NOx) according to the ISO 22197 and ISO 22197-1 methodology. The efficiency of acetaldehyde removal under UV irradiation was negligible for all g-C3N4 samples. This can be explained by the fact that g-C3N4 under irradiation does not directly form hydroxyl radicals, which are the primary oxidation species in acetaldehyde oxidation. It was proved by electron paramagnetic resonance (EPR) spectroscopy that the dominant species formed on the irradiated surface of g-C3N4 was the superoxide radical. Its production was responsible for a very high NOx removal efficiency not only under UV irradiation (which was comparable with that of TiO2), but also under visible irradiation.
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Affiliation(s)
- Michal Baudys
- Department of Inorganic Technology, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic; (M.B.); (Š.P.)
| | - Šárka Paušová
- Department of Inorganic Technology, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic; (M.B.); (Š.P.)
| | - Petr Praus
- Institute of Environmental Technology, VŠB-Technical University of Ostrava, 17. listopadu 2172/15, 708 00 Ostrava-Poruba, Czech Republic;
| | - Vlasta Brezová
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37 Bratislava, Slovak Republic; (V.B.); (D.D.); (Z.B.)
| | - Dana Dvoranová
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37 Bratislava, Slovak Republic; (V.B.); (D.D.); (Z.B.)
| | - Zuzana Barbieriková
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37 Bratislava, Slovak Republic; (V.B.); (D.D.); (Z.B.)
| | - Josef Krýsa
- Department of Inorganic Technology, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic; (M.B.); (Š.P.)
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Lin Y, Yan Y, Peng W, Qiao X, Huang D, Ji H, Chen C, Ma W, Zhao J. Crucial Effect of Ti-H Species Generated in the Visible-Light-Driven Transformations: Slowed-Down Proton-Coupled Electron Transfer. J Phys Chem Lett 2020; 11:3941-3946. [PMID: 32353238 DOI: 10.1021/acs.jpclett.0c01196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Despite the fact that proton-coupled electron transfer (PCET) has been hypothesized to play a pivotal role in the power conversion efficiency (PCE) of TiO2-based solar-energy applications, the specific relationship between the intrinsic nature of visible-light (Vis)-driven PCET reactions and limited PCE gains has not yet been well revealed. Here we studied the detailed kinetics of reactions between various alcohols and radicals (tBu3ArO•/TEMPO) on a TiO2 photocatalyst under dye-sensitization Vis irradiation versus direct ultraviolet (UV) irradiation. We found that the rates of Vis-driven reactions were much slower than those of UV-driven reactions under identical light intensity. A similar phenomenon was observed under the off-line dark-reaction conditions in which TiO2 was prereduced by alcohols. The rapid formation and difficult breakage of the stable "Ti-H" intermediate were proposed to account for the slowed-down PCET effect. This finding revealed an inherent bottleneck in Vis-driven energy conversion applications.
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Affiliation(s)
- Yuhan Lin
- Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yan Yan
- Jiangsu University, Zhenjiang 212013, P. R. China
| | - Wei Peng
- Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Xiaofeng Qiao
- Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Di Huang
- Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hongwei Ji
- Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chuncheng Chen
- Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Wanhong Ma
- Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jincai Zhao
- Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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10
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Imparato C, Iervolino G, Fantauzzi M, Koral C, Macyk W, Kobielusz M, D'Errico G, Rea I, Di Girolamo R, De Stefano L, Andreone A, Vaiano V, Rossi A, Aronne A. Photocatalytic hydrogen evolution by co-catalyst-free TiO 2/C bulk heterostructures synthesized under mild conditions. RSC Adv 2020; 10:12519-12534. [PMID: 35497602 PMCID: PMC9051216 DOI: 10.1039/d0ra01322f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 03/17/2020] [Indexed: 01/01/2023] Open
Abstract
Hydrogen production by photocatalytic water splitting is one of the most promising sustainable routes to store solar energy in the form of chemical bonds. To obtain significant H2 evolution rates (HERs) a variety of defective TiO2 catalysts were synthesized by means of procedures generally requiring highly energy-consuming treatments, e.g. hydrogenation. Even if a complete understanding of the relationship between defects, electronic structure and catalytic active sites is far from being achieved, the band gap narrowing and Ti3+-self-doping have been considered essential to date. In most reports a metal co-catalyst (commonly Pt) and a sacrificial electron donor (such as methanol) are used to improve HERs. Here we report the synthesis of TiO2/C bulk heterostructures, obtained from a hybrid TiO2-based gel by simple heat treatments at 400 °C under different atmospheres. The electronic structure and properties of the grey or black gel-derived powders are deeply inspected by a combination of classical and less conventional techniques, in order to identify the origin of their photoresponsivity. The defective sites of these heterostructures, namely oxygen vacancies, graphitic carbon and unpaired electrons localized on the C matrix, result in a remarkable visible light activity in spite of the lack of band gap narrowing or Ti3+-self doping. The materials provide HER values ranging from about 0.15 to 0.40 mmol h-1 gcat -1, under both UV- and visible-light irradiation, employing glycerol as sacrificial agent and without any co-catalyst.
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Affiliation(s)
- Claudio Imparato
- Department of Chemical, Materials and Production Engineering, University of Naples Federico II P.le V. Tecchio 80 80125 Napoli Italy
| | - Giuseppina Iervolino
- Department of Industrial Engineering, University of Salerno Via Giovanni Paolo II 132 84084 Fisciano (Salerno) Italy
| | - Marzia Fantauzzi
- Department of Chemical and Geological Sciences, University of Cagliari S.S. 554 Bivio per Sestu 09042 Monserrato Cagliari Italy
| | - Can Koral
- Department of Physics, University of Naples Federico II, CNR-SPIN, UOS Napoli Via Cinthia 80126 Napoli Italy
| | - Wojciech Macyk
- Faculty of Chemistry, Jagiellonian University ul. Gronostajowa 2 30-387 Kraków Poland
| | - Marcin Kobielusz
- Faculty of Chemistry, Jagiellonian University ul. Gronostajowa 2 30-387 Kraków Poland
| | - Gerardino D'Errico
- Department of Chemical Sciences, University of Naples Federico II Via Cinthia 80126 Napoli Italy
| | - Ilaria Rea
- Institute for Microelectronics and Microsystems, National Research Council Via P. Castellino 111 80131 Napoli Italy
| | - Rocco Di Girolamo
- Department of Chemical Sciences, University of Naples Federico II Via Cinthia 80126 Napoli Italy
| | - Luca De Stefano
- Institute for Microelectronics and Microsystems, National Research Council Via P. Castellino 111 80131 Napoli Italy
| | - Antonello Andreone
- Department of Physics, University of Naples Federico II, CNR-SPIN, UOS Napoli Via Cinthia 80126 Napoli Italy
| | - Vincenzo Vaiano
- Department of Industrial Engineering, University of Salerno Via Giovanni Paolo II 132 84084 Fisciano (Salerno) Italy
| | - Antonella Rossi
- Department of Chemical and Geological Sciences, University of Cagliari S.S. 554 Bivio per Sestu 09042 Monserrato Cagliari Italy
| | - Antonio Aronne
- Department of Chemical, Materials and Production Engineering, University of Naples Federico II P.le V. Tecchio 80 80125 Napoli Italy
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Vatti SK, Gupta S, Raj RP, Selvam P. Periodic mesoporous titania with anatase and bronze phases – the new generation photocatalyst: synthesis, characterisation, and application in environmental remediation. NEW J CHEM 2020. [DOI: 10.1039/d0nj02457k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A facile synthesis of mesoporous titania with a unique anatase and bronze phases is reported. The resulting material favours a slow recombination of excitons which make promise for photocatalytic degradation of famotidine and 4-chlorophenol.
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Affiliation(s)
- Surya Kumar Vatti
- National Centre for Catalysis Research and Department of Chemistry
- Indian Institute of Technology-Madras
- Chennai
- India
| | - Sanjeev Gupta
- National Centre for Catalysis Research and Department of Chemistry
- Indian Institute of Technology-Madras
- Chennai
- India
| | - Rayappan Pavul Raj
- National Centre for Catalysis Research and Department of Chemistry
- Indian Institute of Technology-Madras
- Chennai
- India
| | - Parasuraman Selvam
- National Centre for Catalysis Research and Department of Chemistry
- Indian Institute of Technology-Madras
- Chennai
- India
- School of Chemical Engineering and Analytical Science
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12
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Photocatalytic Hydrogen Production by Boron Modified TiO
2
/Carbon Nitride Heterojunctions. ChemCatChem 2019. [DOI: 10.1002/cctc.201901703] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Schlomberg H, Kröger J, Savasci G, Terban MW, Bette S, Moudrakovski I, Duppel V, Podjaski F, Siegel R, Senker J, Dinnebier RE, Ochsenfeld C, Lotsch BV. Structural Insights into Poly(Heptazine Imides): A Light-Storing Carbon Nitride Material for Dark Photocatalysis. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2019; 31:7478-7486. [PMID: 31582875 PMCID: PMC6768190 DOI: 10.1021/acs.chemmater.9b02199] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 08/09/2019] [Indexed: 05/12/2023]
Abstract
Solving the structure of carbon nitrides has been a long-standing challenge due to the low crystallinity and complex structures observed within this class of earth-abundant photocatalysts. Herein, we report on two-dimensional layered potassium poly(heptazine imide) (K-PHI) and its proton-exchanged counterpart (H-PHI), obtained by ionothermal synthesis using a molecular precursor route. We present a comprehensive analysis of the in-plane and three-dimensional structure of PHI. Transmission electron microscopy and solid-state NMR spectroscopy, supported by quantum-chemical calculations, suggest a planar, imide-bridged heptazine backbone with trigonal symmetry in both K-PHI and H-PHI, whereas pair distribution function analyses and X-ray powder diffraction using recursive-like simulations of planar defects point to a structure-directing function of the pore content. While the out-of-plane structure of K-PHI exhibits a unidirectional layer offset, mediated by hydrated potassium ions, H-PHI is characterized by a high degree of stacking faults due to the weaker structure directing influence of pore water. Structure-property relationships in PHI reveal that a loss of in-plane coherence, materializing in smaller lateral platelet dimensions and increased terminal cyanamide groups, correlates with improved photocatalytic performance. Size-optimized H-PHI is highly active toward photocatalytic hydrogen evolution, with a rate of 3363 μmol/gh H2 placing it on par with the most active carbon nitrides. K- and H-PHI adopt a uniquely long-lived photoreduced polaronic state in which light-induced electrons are stored for more than 6 h in the dark and released upon addition of a Pt cocatalyst. This work highlights the importance of structure-property relationships in carbon nitrides for the rational design of highly active hydrogen evolution photocatalysts.
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Affiliation(s)
- Hendrik Schlomberg
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
- Department
Chemie, Ludwig-Maximilians-Universität
München, Butenandtstraße
5−13, 81377 München, Germany
- Center
for Nanoscience and Cluster of excellence e-conversion, Schellingstraße 4, 80799 München, Germany
| | - Julia Kröger
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
- Department
Chemie, Ludwig-Maximilians-Universität
München, Butenandtstraße
5−13, 81377 München, Germany
- Center
for Nanoscience and Cluster of excellence e-conversion, Schellingstraße 4, 80799 München, Germany
| | - Gökcen Savasci
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
- Department
Chemie, Ludwig-Maximilians-Universität
München, Butenandtstraße
5−13, 81377 München, Germany
- Center
for Nanoscience and Cluster of excellence e-conversion, Schellingstraße 4, 80799 München, Germany
| | - Maxwell W. Terban
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Sebastian Bette
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Igor Moudrakovski
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Viola Duppel
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Filip Podjaski
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Renée Siegel
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95440 Bayreuth, Germany
| | - Jürgen Senker
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95440 Bayreuth, Germany
| | - Robert E. Dinnebier
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Christian Ochsenfeld
- Department
Chemie, Ludwig-Maximilians-Universität
München, Butenandtstraße
5−13, 81377 München, Germany
- Center
for Nanoscience and Cluster of excellence e-conversion, Schellingstraße 4, 80799 München, Germany
| | - Bettina V. Lotsch
- Max-Planck-Institut
für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
- Department
Chemie, Ludwig-Maximilians-Universität
München, Butenandtstraße
5−13, 81377 München, Germany
- Center
for Nanoscience and Cluster of excellence e-conversion, Schellingstraße 4, 80799 München, Germany
- E-mail:
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15
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Zhao C, Yan Q, Wang S, Dong P, Zhang L. Regenerable g-C3N4–chitosan beads with enhanced photocatalytic activity and stability. RSC Adv 2018; 8:27516-27524. [PMID: 35540016 PMCID: PMC9083882 DOI: 10.1039/c8ra04293d] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Accepted: 07/25/2018] [Indexed: 01/19/2023] Open
Abstract
In this study, a series of regenerable graphitic carbon nitride–chitosan (g-C3N4–CS) beads were successfully synthesized via the blend crosslinking method. The prepared beads were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The structural characterization results indicate that the g-C3N4 granules were uniformly distributed on the surface of the chitosan matrix, and the structures of g-C3N4 and CS are maintained. In addition, the prepared g-C3N4–CS beads exhibited efficient MB degradation and stability. The optimum photocatalytic activity of our synthesized g-C3N4–CS beads was higher than that of the bulk g-C3N4 by a factor of 1.78 for MB. The improved photocatalytic activity was predominantly attributed to the synergistic effect between in situ adsorption and photocatalytic degradation. In addition, the reacted g-C3N4–CS beads can be regenerated by merely adding sodium hydroxide and hydrogen peroxide. Additionally, the regenerated g-C3N4–CS beads exhibit excellent stability after four runs, while the mass loss is less than 10%. This work might provide guidance for the design and fabrication of easily regenerated g-C3N4-based photocatalysts for environmental purification. In this study, a series of regenerable graphitic carbon nitride–chitosan (g-C3N4–CS) beads were successfully synthesized via the blend crosslinking method.![]()
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Affiliation(s)
- Chaocheng Zhao
- State Key Laboratory of Petroleum Pollution Control
- China University of Petroleum (East China)
- Qingdao
- PR China
| | - Qingyun Yan
- State Key Laboratory of Petroleum Pollution Control
- China University of Petroleum (East China)
- Qingdao
- PR China
| | - Shuaijun Wang
- State Key Laboratory of Petroleum Pollution Control
- China University of Petroleum (East China)
- Qingdao
- PR China
| | - Pei Dong
- State Key Laboratory of Petroleum Pollution Control
- China University of Petroleum (East China)
- Qingdao
- PR China
| | - Liang Zhang
- State Key Laboratory of Petroleum Pollution Control
- China University of Petroleum (East China)
- Qingdao
- PR China
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