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Cai K, Yu J, Tan W, Gao C, Zhao Z, Yuan S, Cheng J, Yang Y, Yuan Y. The Incorporation of Sulfonated PAF Enhances the Proton Conductivity of Nafion Membranes at High Temperatures. Polymers (Basel) 2024; 16:2208. [PMID: 39125234 PMCID: PMC11314880 DOI: 10.3390/polym16152208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 07/02/2024] [Accepted: 07/30/2024] [Indexed: 08/12/2024] Open
Abstract
Nafion membranes are widely used as proton exchange membranes, but their proton conductivity deteriorates in high-temperature environments due to the loss of water molecules. To address this challenge, we propose the utilization of porous aromatic frameworks (PAFs) as a potential solution. PAFs exhibit remarkable characteristics, such as a high specific surface area and porosity, and their porous channels can be post-synthesized. Here, a novel approach was employed to synthesize a PAF material, designated as PAF-45D, which exhibits a specific surface area of 1571.9 m2·g-1 and possesses the added benefits of facile synthesis and a low cost. Subsequently, sulfonation treatment was applied to PAF-45D in order to introduce sulfonic acid groups into its pores, resulting in the formation of PAF-45DS. The successful incorporation of sulfonic groups was confirmed through TG, IR, and EDS analyses. Furthermore, a novel Nafion composite membrane was prepared by incorporating PAF-45DS. The Nyquist plot of the composite membranes demonstrates that the sulfonated PAF-45DS material can enhance the proton conductivity of Nafion membranes at high temperatures. Specifically, under identical film formation conditions, doping with a 4% mass fraction of PAF-45DS, the conductivity of the Nafion composite membrane increased remarkably from 2.25 × 10-3 S·cm-1 to 5.67 × 10-3 S·cm-1, nearly 2.5 times higher. Such promising and cost-effective materials could be envisioned for application in the field of Nafion composite membranes.
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Affiliation(s)
- Kun Cai
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Xuchang 461000, China; (J.Y.); (W.T.); (C.G.); (S.Y.); (J.C.)
| | - Jinzhu Yu
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Xuchang 461000, China; (J.Y.); (W.T.); (C.G.); (S.Y.); (J.C.)
| | - Wenjun Tan
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Xuchang 461000, China; (J.Y.); (W.T.); (C.G.); (S.Y.); (J.C.)
| | - Cong Gao
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Xuchang 461000, China; (J.Y.); (W.T.); (C.G.); (S.Y.); (J.C.)
| | - Zili Zhao
- XuJue Electric Co., Ltd., Xuchang 461000, China;
| | - Suxin Yuan
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Xuchang 461000, China; (J.Y.); (W.T.); (C.G.); (S.Y.); (J.C.)
| | - Jinghui Cheng
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Xuchang 461000, China; (J.Y.); (W.T.); (C.G.); (S.Y.); (J.C.)
| | - Yajie Yang
- Key Laboratory of Automobile Materials of Ministry of Education, School of Materials Science and Engineering, Jilin University, Changchun 130022, China
| | - Ye Yuan
- Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education, Northeast Normal University, Changchun 130024, China;
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2
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Winterstein SF, Bettermann M, Timm J, Marschall R, Senker J. Thermodynamically Stable Functionalization of Microporous Aromatic Frameworks with Sulfonic Acid Groups by Inserting Methylene Spacers. Molecules 2024; 29:1666. [PMID: 38611945 PMCID: PMC11013227 DOI: 10.3390/molecules29071666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/02/2024] [Accepted: 04/06/2024] [Indexed: 04/14/2024] Open
Abstract
Porous aromatic frameworks (PAFs) are an auspicious class of materials that allow for the introduction of sulfonic acid groups at the aromatic core units by post-synthetic modification. This makes PAFs promising for proton-exchange materials. However, the limited thermal stability of sulfonic acid groups attached to aromatic cores prevents high-temperature applications. Here, we present a framework based on PAF-303 where the acid groups were added as methylene sulfonic acid side chains in a two-step post-synthetic route (SMPAF-303) via the intermediate chloromethylene PAF (ClMPAF-303). Elemental analysis, NMR spectroscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy were used to characterize both frameworks and corroborate the successful attachment of the side chains. The resulting framework SMPAF-303 features high thermal stability and an ion-exchange capacity of about 1.7 mequiv g-1. The proton conductivity depends strongly on the adsorbed water level. It reaches from about 10-7 S cm-1 for 33% RH to about 10-1 S cm-1 for 100% RH. We attribute the strong change to a locally alternating polarity of the inner surfaces. The latter introduces bottleneck effects for the water molecule and oxonium ion diffusion at lower relative humidities, due to electrolyte clustering. When the pores are completely filled with water, these bottlenecks vanish, leading to an unhindered electrolyte diffusion through the framework, explaining the conductivity rise.
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Affiliation(s)
- Simon F. Winterstein
- Inorganic Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitaetsstrasse 30, 95447 Bayreuth, Germany
| | - Michael Bettermann
- Inorganic Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitaetsstrasse 30, 95447 Bayreuth, Germany
| | - Jana Timm
- Physical Chemistry III, Department of Chemistry, University of Bayreuth, Universitaetsstr. 30, 95447 Bayreuth, Germany (R.M.)
| | - Roland Marschall
- Physical Chemistry III, Department of Chemistry, University of Bayreuth, Universitaetsstr. 30, 95447 Bayreuth, Germany (R.M.)
| | - Jürgen Senker
- Inorganic Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitaetsstrasse 30, 95447 Bayreuth, Germany
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3
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Winterstein S, Privalov AF, Greve C, Siegel R, Pötzschner B, Bettermann M, Adolph L, Timm J, Marschall R, Rössler EA, Herzig EM, Vogel M, Senker J. Ultrafast Proton Conduction in an Aqueous Electrolyte Confined in Adamantane-like Micropores of a Sulfonated, Aromatic Framework. J Am Chem Soc 2023; 145:27563-27575. [PMID: 38060438 PMCID: PMC10740000 DOI: 10.1021/jacs.3c09257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/12/2023] [Accepted: 11/20/2023] [Indexed: 12/21/2023]
Abstract
Sulfonated, cross-linked porous polymers are promising frameworks for aqueous high-performance electrolyte-host systems for electrochemical energy storage and conversion. The systems offer high proton conductivities, excellent chemical and mechanical stabilities, and straightforward water management. However, little is known about mass transport mechanisms in such nanostructured hosts. We report on the synthesis and postsynthetic sulfonation of an aromatic framework (SPAF-2) with a 3D-interconnected nanoporosity and varying sulfonation degrees. Water adsorption produces the system SPAF-2H20. It features proton exchange capacities up to 6 mequiv g-1 and exceptional proton conductivities of about 1 S cm-1. Two contributions are essential for the highly efficient transport. First, the nanometer-sized pores link the charge transport to the diffusion of adsorbed water molecules, which is almost as fast as bulk water. Second, continuous exchange between interface-bound and mobile species enhances the conductivities at elevated temperatures. SPAF-2H20 showcases how to tailor nanostructured electrolyte-host systems with liquid-like conductivities.
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Affiliation(s)
- Simon
F. Winterstein
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Alexei F. Privalov
- Institute
for Condensed Matter Physics, Technical
University of Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Christopher Greve
- Dynamics
and Structure Formation, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Renée Siegel
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Björn Pötzschner
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Michael Bettermann
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Lea Adolph
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Jana Timm
- Physical
Chemistry III, Department of Chemistry, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Roland Marschall
- Physical
Chemistry III, Department of Chemistry, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Ernst A. Rössler
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Eva M. Herzig
- Dynamics
and Structure Formation, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Michael Vogel
- Institute
for Condensed Matter Physics, Technical
University of Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Jürgen Senker
- Inorganic
Chemistry III and Northern Bavarian NMR Centre, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
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4
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Zhai L, Yao Y, Ma B, Hasan MM, Han Y, Mi L, Nagao Y, Li Z. Accumulation of Sulfonic Acid Groups Anchored in Covalent Organic Frameworks as an Intrinsic Proton-Conducting Electrolyte. Macromol Rapid Commun 2021; 43:e2100590. [PMID: 34612557 DOI: 10.1002/marc.202100590] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 09/30/2021] [Indexed: 12/25/2022]
Abstract
Covalent organic frameworks (COFs) are a novel class of crystalline porous polymers, which possess high porosity, excellent stability, and regular nanochannels. 2D COFs provide a 1D nanochannel to form the proton transport channels. The abovementioned features afford a powerful potential platform for designing materials as proton transportation carriers. Herein, the authors incorporate sulfonic acid groups on the pore walls as proton sources for enhancing proton transport conductivity in the 1D channel. Interestingly, the sulfonic acid COFs (S-COFs) electrolytes being binder free exhibit excellent proton conductivity of ≈1.5 × 10-2 S cm-1 at 25 ℃ and 95% relative humidity (RH), which rank the excellent performance in standard proton-conducting electrolytes. The S-COFs electrolytes keep the high proton conduction over the 24 h. The activation energy is estimated to be as low as 0.17 eV, which is much lower than most reported COFs. This research opens a new window to evolve great potential of structural design for COFs as the high proton-conducting electrolytes.
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Affiliation(s)
- Lipeng Zhai
- Henan Key Laboratory of Functional Salt Materials, Center for Advanced Materials Research, Zhongyuan University of Technology, Zhengzhou, 450007, P. R. China
| | - Yuze Yao
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa, 923-1292, Japan
| | - Baiwei Ma
- Henan Key Laboratory of Functional Salt Materials, Center for Advanced Materials Research, Zhongyuan University of Technology, Zhengzhou, 450007, P. R. China
| | - Md Mahmudul Hasan
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa, 923-1292, Japan
| | - Yuxi Han
- School of Materials Science and Engineering, Shandong University of Science and Technology, Qingdao, Shandong, 266590, P. R. China
| | - Liwei Mi
- Henan Key Laboratory of Functional Salt Materials, Center for Advanced Materials Research, Zhongyuan University of Technology, Zhengzhou, 450007, P. R. China
| | - Yuki Nagao
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa, 923-1292, Japan
| | - Zhongping Li
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa, 923-1292, Japan
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5
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Akopyan AV, Kulikov LA, Polikarpova PD, Shlenova AO, Anisimov AV, Maximov AL, Karakhanov EA. Metal-Free Oxidative Desulfurization Catalysts Based on Porous Aromatic Frameworks. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c00886] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Argam V. Akopyan
- Chemistry Department, Lomonosov Moscow State University, 1-3 Leninskiye Gory, 119991 Moscow, Russia
| | - Leonid A. Kulikov
- Chemistry Department, Lomonosov Moscow State University, 1-3 Leninskiye Gory, 119991 Moscow, Russia
| | - Polina D. Polikarpova
- Chemistry Department, Lomonosov Moscow State University, 1-3 Leninskiye Gory, 119991 Moscow, Russia
| | - Anna O. Shlenova
- Chemistry Department, Lomonosov Moscow State University, 1-3 Leninskiye Gory, 119991 Moscow, Russia
| | - Alexander V. Anisimov
- Chemistry Department, Lomonosov Moscow State University, 1-3 Leninskiye Gory, 119991 Moscow, Russia
| | - Anton L. Maximov
- Chemistry Department, Lomonosov Moscow State University, 1-3 Leninskiye Gory, 119991 Moscow, Russia
- A.V.Topchiev Institute of Petrochemical Synthesis, 29 Leninsky Prospect, 119991 Moscow, Russia
| | - Eduard A. Karakhanov
- Chemistry Department, Lomonosov Moscow State University, 1-3 Leninskiye Gory, 119991 Moscow, Russia
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6
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Yang Z, Chen P, Hao W, Xie Z, Feng Y, Xing G, Chen L. Sulfonated 2D Covalent Organic Frameworks for Efficient Proton Conduction. Chemistry 2021; 27:3817-3822. [DOI: 10.1002/chem.202004727] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Zongfan Yang
- Department of Chemistry, Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Tianjin 300072 China
| | - Pei Chen
- Department of Chemistry, Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Tianjin 300072 China
| | - Wenjing Hao
- Department of Chemistry, Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Tianjin 300072 China
| | - Zhen Xie
- Department of Chemistry, Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Tianjin 300072 China
| | - Yu Feng
- Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function, Institution of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Guolong Xing
- Department of Chemistry, Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Tianjin 300072 China
| | - Long Chen
- Department of Chemistry, Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Tianjin 300072 China
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7
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Du J, Zhang F, Liang X, Qu F. Influence of chemical composition on the proton conductivity of microporous organic polymers entrapped in nitrilotrimethylphosphonic acid. NEW J CHEM 2021. [DOI: 10.1039/d1nj02385c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The construction of acid–base interactions is critical for developing proton-conducting COF materials with high loading and stable electrolytes, which is influenced by the chemical composition of conductors.
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Affiliation(s)
- Jiarui Du
- Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Heilongjiang Province and College of Chemistry and Chemical Engineering, Harbin Normal University, Harbin 150025, P. R. China
| | - Feng Zhang
- Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Heilongjiang Province and College of Chemistry and Chemical Engineering, Harbin Normal University, Harbin 150025, P. R. China
| | - Xiaoqiang Liang
- College of Environmental and Chemical Engineering, Xi’an Polytechnic University, Xi’an 710048, P. R. China
| | - Fengyu Qu
- Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Heilongjiang Province and College of Chemistry and Chemical Engineering, Harbin Normal University, Harbin 150025, P. R. China
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8
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Introduction of H2SO4 and H3PO4 into Crystalline Porous Organic Salts(CPOS-1) for Outstanding Proton Conductivity. Chem Res Chin Univ 2020. [DOI: 10.1007/s40242-020-9276-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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9
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Mukhopadhyay S, Debgupta J, Singh C, Sarkar R, Basu O, Das SK. Designing UiO-66-Based Superprotonic Conductor with the Highest Metal-Organic Framework Based Proton Conductivity. ACS APPLIED MATERIALS & INTERFACES 2019; 11:13423-13432. [PMID: 30888148 DOI: 10.1021/acsami.9b01121] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Metal-organic framework (MOF) based proton conductors have received immense importance recently. The present study endeavors to design two post synthetically modified UiO-66-based MOFs and examines the effects of their structural differences on their proton conductivity. UiO-66-NH2 is modified by reaction with sultones to prepare two homologous compounds, that is, PSM 1 and PSM 2, with SO3H functionalization in comparable extent (Zr:S = 2:1) in both. However, the pendant alkyl chain holding the -SO3H group is of different length. PSM 2 has longer alkyl chain attachment than PSM 1. This difference in the length of side arms results in a huge difference in proton conductivity of the two compounds. PSM 1 is observed to have the highest MOF-based proton conductivity (1.64 × 10-1 S cm-1) at 80 °C, which is comparable to commercially available Nafion, while PSM 2 shows significantly lower conductivity (4.6 × 10-3 S cm-1). Again, the activation energy for proton conduction is one of the lowest among all MOF-based proton conductors in the case of PSM 1, while PSM 2 requires larger activation energy (almost 3 times). This profound effect of variation of the chain length of the side arm by one carbon atom in the case of PSM 1 and PSM 2 was rather surprising and never documented before. This effect of the length of the side arm can be very useful to understand the proton conduction mechanism of MOF-based compounds and also to design better proton conductors. Besides, PSM 1 showed proton conductivity as high as 1.64 × 10-1 S cm-1 at 80 °C, which is the highest reported value to date among all MOF-based systems. The lability of the -SO3H proton of the post synthetically modified UiO-66 MOFs has theoretically been determined by molecular electrostatic potential analysis and theoretical p Ka calculation of models of functional sites along with relevant NBO analyses.
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Affiliation(s)
| | - Joyashish Debgupta
- School of Chemistry , University of Hyderabad , Hyderabad 500046 , India
| | - Chandani Singh
- School of Chemistry , University of Hyderabad , Hyderabad 500046 , India
| | - Rudraditya Sarkar
- School of Chemistry , University of Hyderabad , Hyderabad 500046 , India
| | - Olivia Basu
- School of Chemistry , University of Hyderabad , Hyderabad 500046 , India
| | - Samar K Das
- School of Chemistry , University of Hyderabad , Hyderabad 500046 , India
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Cho K, Lee SM, Kim HJ, Ko YJ, Son SU. Nanoparticulate and microporous solid acid catalysts bearing aliphatic sulfonic acids for biomass conversion. Chem Commun (Camb) 2019; 55:3697-3700. [PMID: 30799477 DOI: 10.1039/c9cc00436j] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
This work introduces new nanocatalytic systems based on microporous organic network (MON) chemistry for fructose conversion to 5-hydroxymethylfurfural (HMF). The efficiency of the catalytic systems could be improved through the size-controlled synthesis of MON materials. Through a predesigned building block approach and a post-synthetic modification, aliphatic sulfonic acid groups were incorporated into nano-sized MON materials to form N-MON-AS. The N-MON-AS showed selective conversion of fructose to HMF in up to 91% yield at 100 °C and good recyclability.
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Affiliation(s)
- Kyoungil Cho
- Department of Chemistry, Sungkyunkwan University, Suwon 16419, Korea.
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11
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Yang SJ, Ding X, Han BH. Conjugated Microporous Polymers with Dense Sulfonic Acid Groups as Efficient Proton Conductors. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:7640-7646. [PMID: 29877710 DOI: 10.1021/acs.langmuir.8b00926] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Proton-exchange membrane fuel cells, emerging as green and sustainable energy sources, have attracted extensive attention in recent decades. Porous organic polymers, which feature in high surface area values, tunable pore sizes, excellent thermal and chemical stabilities, and the flexibility to incorporate specific functional groups, have recently displayed their striking images as potential electrolytes for fuel cells. In this work, BO-CMP-1 and BO-CMP-2 that possess rich π-structure and permanent porosity and have high thermal and chemical stability were synthesized through Suzuki-Miyaura coupling reaction. Owing to their rigid structures and abundant electrophilic substitution positions, these two novel porous polymers were covalently decorated with dense sulfonic acid groups by postsulfonation, as denoted by SBO-CMP-1 and SBO-CMP-2. The proton conductivity of SBO-CMPs is systematically studied to evaluate their performance as proton-conductive materials. It was found that their performance is highly humidity- and temperature-dependent and they show relatively high proton conductivity. For SBO-CMP-1 and SBO-CMP-2, their proton conductivities are 1.29 × 10-2 and 5.21 × 10-3 S cm-1, respectively, at 70 °C and 100% relative humidity. Low activation energy values of 0.32 eV for SBO-CMP-1 and 0.40 eV for SBO-CMP-2 suggest the Grotthuss mechanism for proton conduction.
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Affiliation(s)
- Si-Jie Yang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience , National Center for Nanoscience and Technology , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Xuesong Ding
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience , National Center for Nanoscience and Technology , Beijing 100190 , China
| | - Bao-Hang Han
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience , National Center for Nanoscience and Technology , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
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