Co-reporter:Guiqing Lin, Huimin Ding, Rufan Chen, Zhengkang Peng, Baoshan Wang, and Cheng Wang
Journal of the American Chemical Society June 28, 2017 Volume 139(Issue 25) pp:8705-8705
Publication Date(Web):June 8, 2017
DOI:10.1021/jacs.7b04141
The design and synthesis of three-dimensional covalent organic frameworks (3D COFs) bearing photoelectric units have been considered as a big challenge. Herein, for the first time, we reported the targeted synthesis of two 3D porphyrin-based COFs (3D-Por-COF and 3D-CuPor-COF), starting from tetrahedral (3D-Td) and square (2D-C4) building blocks connected through [4 + 4] imine condensation reactions. On the basis of structural characterizations, 3D-Por-COF and 3D-CuPor-COF are microporous materials with high surface areas, and are proposed to adopt a 2-fold interpenetrated pts topology with Pmc21 space group. Interestingly, both 3D COFs are photosensitive and can be used as heterogeneous catalyst for generating singlet oxygen under photoirradiation. However, 3D-Por-COF shows enhanced photocatalytic activity compared with 3D-CuPor-COF, indicating the properties of 3D porphyrin-based COFs can be tuned by metalation of porphyrin rings. The results reported here will greatly inspire us to design and synthesize 3D COFs bearing other metalloporphyrins for interesting applications (e.g., catalysis) in the future.
Co-reporter:Guiqing Lin, Huimin Ding, Rufan Chen, Zhengkang Peng, Baoshan Wang, and Cheng Wang
Journal of the American Chemical Society June 28, 2017 Volume 139(Issue 25) pp:8705-8705
Publication Date(Web):June 8, 2017
DOI:10.1021/jacs.7b04141
The design and synthesis of three-dimensional covalent organic frameworks (3D COFs) bearing photoelectric units have been considered as a big challenge. Herein, for the first time, we reported the targeted synthesis of two 3D porphyrin-based COFs (3D-Por-COF and 3D-CuPor-COF), starting from tetrahedral (3D-Td) and square (2D-C4) building blocks connected through [4 + 4] imine condensation reactions. On the basis of structural characterizations, 3D-Por-COF and 3D-CuPor-COF are microporous materials with high surface areas, and are proposed to adopt a 2-fold interpenetrated pts topology with Pmc21 space group. Interestingly, both 3D COFs are photosensitive and can be used as heterogeneous catalyst for generating singlet oxygen under photoirradiation. However, 3D-Por-COF shows enhanced photocatalytic activity compared with 3D-CuPor-COF, indicating the properties of 3D porphyrin-based COFs can be tuned by metalation of porphyrin rings. The results reported here will greatly inspire us to design and synthesize 3D COFs bearing other metalloporphyrins for interesting applications (e.g., catalysis) in the future.
Co-reporter:Guiqing Lin; Huimin Ding; Daqiang Yuan; Baoshan Wang
Journal of the American Chemical Society 2016 Volume 138(Issue 10) pp:3302-3305
Publication Date(Web):February 29, 2016
DOI:10.1021/jacs.6b00652
The targeted synthesis of 3D COFs has been considered challenging, especially adopting new topologies and bearing photoelectric units. Herein, for the first time, we report the synthesis and characterization of a novel 3D pyrene-based COF (3D-Py-COF), by selectively choosing the geometry of the precursors and the connection patterns. Based on X-ray diffraction measurement and detailed simulations, 3D-Py-COF is proposed to adopt a two-fold interpenetrated pts topology, which has never been reported before. In addition, 3D-Py-COF has a narrow pore size distribution and high surface area and also features selective absorption of CO2 over N2. Interestingly, due to the existence of isolated pyrene units in the 3D framework, 3D-Py-COF is the first fluorescent 3D COF and can be used in explosive detection. Our results not only show it is possible to rationally design and synthesize 3D COFs with other topologies but also demonstrate that the incorporation of photoelectric units into 3D COFs can allow the resulting materials with interesting properties.
Co-reporter:Huaping Liao, Hongmin Wang, Huimin Ding, Xiangshi Meng, Hai Xu, Baoshan Wang, Xinping Ai and Cheng Wang
Journal of Materials Chemistry A 2016 vol. 4(Issue 19) pp:7416-7421
Publication Date(Web):06 Apr 2016
DOI:10.1039/C6TA00483K
Covalent organic frameworks (COFs) represent an emerging class of porous crystalline materials and have recently shown interesting applications in energy storage. Herein, we report the construction of a cycle-stable sulfur electrode by embedding sulfur into a 2D COF. The designed porphyrin-based COF (Por-COF), featuring a relatively large pore volume and narrow pore size distribution, has been employed as a host material for sulfur storage in Li–S batteries. With a 55% sulfur loading in the composite, the thus-prepared cathode delivers a capacity of 633 mA h g−1 after 200 cycles at 0.5C charge/discharge rates. Therefore, embedding sulfur in the nanopores of the Por-COF significantly improves the performance of the sulfur cathode. Considering the flexible design of COFs, we believe that it is possible to synthesize a 2D COF host with a suitable pore environment to produce more stable Li–S batteries, which may help in exploration of the structure–property relationship between the host material and cell performance.
Co-reporter:Hongmin Wang, Huimin Ding, Xiangshi Meng, Cheng Wang
Chinese Chemical Letters 2016 Volume 27(Issue 8) pp:1376-1382
Publication Date(Web):August 2016
DOI:10.1016/j.cclet.2016.05.020
Covalent organic frameworks (COFs) represent an emerging class of porous crystalline materials and have recently shown interesting applications from catalysis to optoelectronic devices. In this review, by covering most of the reported work, we summarized the research progress of two-dimensional (2D) porphyrin- and phthalocyanine-based COFs, with highlighting the synthesis of these 2D COFs via various dynamic covalent reactions and emphasizing their potential applications in different areas.In this review, we summarized the research progress of two-dimensional (2D) porphyrin- and phthalocyanine-based COFs, with highlighting the synthesis of these 2D COFs via various dynamic covalent reactions and emphasizing their potential applications in different areas.
Co-reporter:Bo Gui;Xiangshi Meng;Hai Xu
Chinese Journal of Chemistry 2016 Volume 34( Issue 2) pp:186-190
Publication Date(Web):
DOI:10.1002/cjoc.201500621
Abstract
The postsynthetic modification (PSM) of metal-organic frameworks (MOFs) has emerged as a powerful tool to chemically tailor the interior of MOFs. In this review, we summarize the research progress of PSM of MOFs through click chemistry, including azide-alkyne click reaction and thiol-ene reaction.
Co-reporter:Xiangshi Meng;Bo Gui;Daqiang Yuan;Matthias Zeller
Science Advances 2016 Vol 2(8) pp:e1600480
Publication Date(Web):03 Aug 2016
DOI:10.1126/sciadv.1600480
A simple strategy to construct a stimuli-responsive mechanized zirconium metal-organic framework for on-command cargo release.
Co-reporter:Bo Gui, Xiangshi Meng, Yi Chen, Jianwu Tian, Guoliang Liu, Chencheng Shen, Matthias Zeller, Daqiang Yuan, and Cheng Wang
Chemistry of Materials 2015 Volume 27(Issue 18) pp:6426
Publication Date(Web):August 28, 2015
DOI:10.1021/acs.chemmater.5b02648
Transferring the solution-state chemistry of organic-based molecular switches (OMS) into the solid state usually faces several fatal problems, such as spatial confinement or inefficient conversion. As a result, their switching behavior usually cannot be maintained. Herein, we report a redox-switchable metal–organic framework (MOF) that can undergo a reversible single-crystal-to-single-crystal (SCSC) transformation through a hydroquinone/quinone redox reaction. The redox-triggered transformation is quantitatively reversible while maintaining the crystallinity of the MOF scaffold. In addition, the transformation occurs gradually in the MOF backbone and from the outsurface of MOF to the inside. This study represents a general strategy to enable efficient conversion of the functionality of an OMS from solution into solid state, by incorporation of OMS into the framework of MOF. Furthermore, the material exhibits interesting changes in spectroscopic properties through reversible SCSC transformation and, thus, may be a starting point for the use of such materials in memory storage or redox-based electronic devices.
Co-reporter:Huimin Ding, Yihui Yang, Bijian Li, Feng Pan, Guozhu Zhu, Matthias Zeller, Daqiang Yuan and Cheng Wang
Chemical Communications 2015 vol. 51(Issue 10) pp:1976-1979
Publication Date(Web):16 Dec 2014
DOI:10.1039/C4CC08883B
Herein, we report the targeted synthesis and solid state assembly of a novel triazine-based [4+6] organic molecular cage. The tetrahedral cage features a large cavity (∼2070 Å3), and after desolvation, the resultant material exhibits a high Brunauer–Emmett–Teller surface area of 1181 m2 g−1 and also features selective adsorption of CO2 over N2.
Co-reporter:Bo Gui, Ka-Kit Yee, Yan-Lung Wong, Shek-Man Yiu, Matthias Zeller, Cheng Wang and Zhengta Xu
Chemical Communications 2015 vol. 51(Issue 32) pp:6917-6920
Publication Date(Web):27 Feb 2015
DOI:10.1039/C5CC00140D
Self-standing thiol (−SH) groups within a Zr(IV)-based metal–organic framework (MOF) anchor Pd(II) atoms for catalytic applications: the spatial constraint prevents the thiol groups from sealing off/poisoning the Pd(II) center, while the strong Pd–S bond precludes Pd leaching, enabling multiple cycles of heterogeneous catalysis to be executed.
Co-reporter:Bo Gui, Ka-Kit Yee, Yan-Lung Wong, Shek-Man Yiu, Matthias Zeller, Cheng Wang and Zhengtao Xu
Chemical Communications 2015 vol. 51(Issue 32) pp:7072-7072
Publication Date(Web):23 Mar 2015
DOI:10.1039/C5CC90141C
Correction for ‘Tackling poison and leach: catalysis by dangling thiol–palladium functions within a porous metal–organic solid’ by Bo Gui et al., Chem. Commun., 2015, DOI: 10.1039/c5cc00140d.
Co-reporter:Bijian Li, Bo Gui, Guiping Hu, Daqiang Yuan, and Cheng Wang
Inorganic Chemistry 2015 Volume 54(Issue 11) pp:5139-5141
Publication Date(Web):May 8, 2015
DOI:10.1021/acs.inorgchem.5b00535
Herein, we report the synthesis and postsynthetic modification of a novel alkyne-tagged zirconium metal–organic framework, UiO-68-alkyne. The alkynyl groups in the pore surface were subjected to a “click” reaction, achieving quantitative conversion and maintaining the crystallinity of the framework.
Co-reporter:Huimin Ding, Xiaojun Wu, Matthias Zeller, Yunpeng Xie, and Cheng Wang
The Journal of Organic Chemistry 2015 Volume 80(Issue 18) pp:9360-9364
Publication Date(Web):September 3, 2015
DOI:10.1021/acs.joc.5b01781
Covalent porphyrinic cages (CPCs) have been a target of interest for years. In this paper, we report the design and synthesis of two CPCs in which the cofacial porphyrins have a distance of 7.66 and 11.96 Å via template-directed imine condensation reactions and through the selective choice of templating linker and diamine length.
Co-reporter:Wei-long Dong, Lin Wang, Hui-min Ding, Lu Zhao, Dong Wang, Cheng Wang, and Li-Jun Wan
Langmuir 2015 Volume 31(Issue 43) pp:11755-11759
Publication Date(Web):October 15, 2015
DOI:10.1021/acs.langmuir.5b02412
The on-surface reactions of tetrathiafulvalene equipped with four benzaldehyde groups (4ATTF) and ditopic diamine molecules are investigated. 4ATTF tends to form large-scale-ordered rhombus structures when reacted with p-phenylenediamine (PPDA). A longer ditopic diamine molecule, 1,1′-biphenyl-4,4′-diamine dihydrochloride (BPDA), causes the domain size of the regular rhombus structure to decrease and triangular and irregular rhombus structures to appear upon reaction with 4ATTF. However, in the rhombus structures formed by different-length ditopic diamine molecules, the single-layer covalent organic frameworks on the graphite surface preferentially orient in alignment with the underlying HOPG substrate lattice.
Co-reporter:Huaping Liao, Huimin Ding, Bijian Li, Xinping Ai and Cheng Wang
Journal of Materials Chemistry A 2014 vol. 2(Issue 23) pp:8854-8858
Publication Date(Web):10 Mar 2014
DOI:10.1039/C4TA00523F
Commercial development of lithium–sulfur (Li–S) batteries is severely hindered by their insufficient cyclability, which is due to the loss of soluble lithium polysulfide intermediates generated during the discharge processes. To overcome this problem, considerable efforts have been devoted to designing novel micro- or nano-structured host materials, aiming to trap soluble polysulfide within the network. Herein, we report a new approach to construct a sulfur electrode by impregnating sulfur into the nanopores of covalent-organic frameworks (COFs). Our results clearly demonstrate that by using a 2D COF as a host material, e.g. CTF-1 (CTF: covalent triazine-based framework), the thus-prepared cathode can show a remarkable positive effect on the capacity retention of Li–S batteries. Considering the unique features of COFs, such as highly flexible molecular design and a controllable pore size, this proof-of-principle study provides new opportunities for materials scientists for tailoring cathode materials in Li–S batteries.
Co-reporter:Huimin Ding, Xiangshi Meng, Xu Cui, Yihui Yang, Tailin Zhou, Caixing Wang, Matthias Zeller and Cheng Wang
Chemical Communications 2014 vol. 50(Issue 76) pp:11162-11164
Publication Date(Web):30 Jul 2014
DOI:10.1039/C4CC05449K
We report a new approach to construct covalent porphyrinic cages with different spacer lengths, in which the cage compounds have been conveniently synthesized in quantitative yields, via DABCO-templated imine condensation reactions.
Co-reporter:Huimin Ding;Yonghai Li;Hui Hu;Dr. Yimeng Sun;Jianguo Wang;Caixing Wang;Dr. Cheng Wang;Dr. Guanxin Zhang;Dr. Baoshan Wang;Dr. Wei Xu;Dr. Deqing Zhang
Chemistry - A European Journal 2014 Volume 20( Issue 45) pp:14614-14618
Publication Date(Web):
DOI:10.1002/chem.201405330
Abstract
Two-dimensional covalent organic frameworks (2D COFs) provide a unique platform for the molecular design of electronic and optoelectronic materials. Here, the synthesis and characterization of an electroactive COF containing the well-known tetrathiafulvalene (TTF) unit is reported. The TTF-COF crystallizes into 2D sheets with an eclipsed AA stacking motif, and shows high thermal stability and permanent porosity. The presence of TTF units endows the TTF-COF with electron-donating ability, which is characterized by cyclic voltammetry. In addition, the open frameworks of TTF-COF are amenable to doping with electron acceptors (e.g., iodine), and the conductivity of TTF-COF bulk samples can be improved by doping. Our results open up a reliable route for the preparation of well-ordered conjugated TTF polymers, which hold great potential for applications in fields from molecular electronics to energy storage.
Co-reporter:Huimin Ding, Xiangshi Meng, Xu Cui, Yihui Yang, Tailin Zhou, Caixing Wang, Matthias Zeller and Cheng Wang
Chemical Communications 2014 - vol. 50(Issue 76) pp:NaN11164-11164
Publication Date(Web):2014/07/30
DOI:10.1039/C4CC05449K
We report a new approach to construct covalent porphyrinic cages with different spacer lengths, in which the cage compounds have been conveniently synthesized in quantitative yields, via DABCO-templated imine condensation reactions.
Co-reporter:Huimin Ding, Yihui Yang, Bijian Li, Feng Pan, Guozhu Zhu, Matthias Zeller, Daqiang Yuan and Cheng Wang
Chemical Communications 2015 - vol. 51(Issue 10) pp:NaN1979-1979
Publication Date(Web):2014/12/16
DOI:10.1039/C4CC08883B
Herein, we report the targeted synthesis and solid state assembly of a novel triazine-based [4+6] organic molecular cage. The tetrahedral cage features a large cavity (∼2070 Å3), and after desolvation, the resultant material exhibits a high Brunauer–Emmett–Teller surface area of 1181 m2 g−1 and also features selective adsorption of CO2 over N2.
Co-reporter:Bo Gui, Ka-Kit Yee, Yan-Lung Wong, Shek-Man Yiu, Matthias Zeller, Cheng Wang and Zhengta Xu
Chemical Communications 2015 - vol. 51(Issue 32) pp:NaN6920-6920
Publication Date(Web):2015/02/27
DOI:10.1039/C5CC00140D
Self-standing thiol (−SH) groups within a Zr(IV)-based metal–organic framework (MOF) anchor Pd(II) atoms for catalytic applications: the spatial constraint prevents the thiol groups from sealing off/poisoning the Pd(II) center, while the strong Pd–S bond precludes Pd leaching, enabling multiple cycles of heterogeneous catalysis to be executed.
Co-reporter:Bo Gui, Ka-Kit Yee, Yan-Lung Wong, Shek-Man Yiu, Matthias Zeller, Cheng Wang and Zhengtao Xu
Chemical Communications 2015 - vol. 51(Issue 32) pp:NaN7072-7072
Publication Date(Web):2015/03/23
DOI:10.1039/C5CC90141C
Correction for ‘Tackling poison and leach: catalysis by dangling thiol–palladium functions within a porous metal–organic solid’ by Bo Gui et al., Chem. Commun., 2015, DOI: 10.1039/c5cc00140d.
Co-reporter:Huaping Liao, Hongmin Wang, Huimin Ding, Xiangshi Meng, Hai Xu, Baoshan Wang, Xinping Ai and Cheng Wang
Journal of Materials Chemistry A 2016 - vol. 4(Issue 19) pp:NaN7421-7421
Publication Date(Web):2016/04/06
DOI:10.1039/C6TA00483K
Covalent organic frameworks (COFs) represent an emerging class of porous crystalline materials and have recently shown interesting applications in energy storage. Herein, we report the construction of a cycle-stable sulfur electrode by embedding sulfur into a 2D COF. The designed porphyrin-based COF (Por-COF), featuring a relatively large pore volume and narrow pore size distribution, has been employed as a host material for sulfur storage in Li–S batteries. With a 55% sulfur loading in the composite, the thus-prepared cathode delivers a capacity of 633 mA h g−1 after 200 cycles at 0.5C charge/discharge rates. Therefore, embedding sulfur in the nanopores of the Por-COF significantly improves the performance of the sulfur cathode. Considering the flexible design of COFs, we believe that it is possible to synthesize a 2D COF host with a suitable pore environment to produce more stable Li–S batteries, which may help in exploration of the structure–property relationship between the host material and cell performance.
Co-reporter:Huaping Liao, Huimin Ding, Bijian Li, Xinping Ai and Cheng Wang
Journal of Materials Chemistry A 2014 - vol. 2(Issue 23) pp:NaN8858-8858
Publication Date(Web):2014/03/10
DOI:10.1039/C4TA00523F
Commercial development of lithium–sulfur (Li–S) batteries is severely hindered by their insufficient cyclability, which is due to the loss of soluble lithium polysulfide intermediates generated during the discharge processes. To overcome this problem, considerable efforts have been devoted to designing novel micro- or nano-structured host materials, aiming to trap soluble polysulfide within the network. Herein, we report a new approach to construct a sulfur electrode by impregnating sulfur into the nanopores of covalent-organic frameworks (COFs). Our results clearly demonstrate that by using a 2D COF as a host material, e.g. CTF-1 (CTF: covalent triazine-based framework), the thus-prepared cathode can show a remarkable positive effect on the capacity retention of Li–S batteries. Considering the unique features of COFs, such as highly flexible molecular design and a controllable pore size, this proof-of-principle study provides new opportunities for materials scientists for tailoring cathode materials in Li–S batteries.
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