Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh...Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh kg-1). The commercialization of Li–S batteries is impeded by several key challenges at cathode side, e.g. the insulating nature of sulfur and discharged products(Li2S 2 and Li2S), the solubility of long-chain polysulfides and volume variation of sulfur cathode upon cycling. Recently, the carbonbased derivatives from metal-organic frameworks(MOFs) has emerged talent in their utilization as cathode hosts for Li–S batteries. They are not only highly conductive and porous to enable the acceleration of Li +/e-transfer and accommodation of volumetric expansion of sulfur cathode during cycling, but also enriched by controllable chemical active sites to enable the adsorption of polysulfides and promotion of their conversion reaction kinetics. In this review, based on the types of MOFs(e.g. ZIF-8, ZIF-67, Prussian blue, Al-MOF, MOF-5, Cu-MOF, Ni-MOF), the synthetic methods, formation process and morphology, structural superiority of MOFs-derived carbon frameworks along with their electrochemical performance as cathode host in Li–S batteries are summarized and discussed.展开更多
Porous structures o er highly accessible surfaces and rich pores, which facilitate the exposure of numerous active sites for photocatalytic reactions, leading to excellent performances. Recently, metal–organic framew...Porous structures o er highly accessible surfaces and rich pores, which facilitate the exposure of numerous active sites for photocatalytic reactions, leading to excellent performances. Recently, metal–organic frameworks(MOFs) have been considered ideal precursors for well-designed semiconductors with porous structures and/or heterostructures, which have shown enhanced photocatalytic activities. In this review, we summarize the recent development of porous structures, such as metal oxides and metal sulfides, and their heterostructures, derived from MOF-based materials as catalysts for various light-driven energy-/environment-related reactions, including water splitting, CO_2 reduction, organic redox reaction, and pollution degradation. A summary and outlook section is also included.展开更多
Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and ene...Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and energy storage, because of their unique structures. In this paper, we prepared a metal-organic framework [(<em>μ</em><sub>2</sub>-2-methylimidazolyl)<sub>12</sub>-Zn(ii)<sub>6</sub>-H<sub>18</sub>O<sub>10</sub>]<sub>n</sub>(ZM) with well-developed pores and high specific surface area of MOFs by the solution method. And MOF-derived porous carbon was prepared by the direct charring method in an argon atmosphere using a mixture of ZM, ZM and potassium citrate as carbon precursors. Characterization analysis revealed that the maximum specific surface area of ZMPC-800-1:15 was 2014.97 m<sup>2</sup><span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, and the pore size structure was mainly mesoporous. At a current density of 1.0 A<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup> the specific capacitance of ZMC-800 and ZMPC-800-1:15 was 121.3 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup> and 226.6 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, respectively, with a substantial increase of 86.8%. The specific capacitance of ZMPC-800-1:15 decays to 168.8 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, with a decay rate of 25.5%, when the current density increases to 10.0 A<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>. After 5000 constant current charge/ discharge cycles, the capacitance retention rate was still 96.41%. These results prove that the application of MOF-derived carbon materials in future supercapacitors is very promising.展开更多
通过二氧化碳(CO_(2))与环氧化物的环加成反应可以将温室气体CO_(2)转化为有价值的化工产品环状碳酸酯,因而对该反应具有高效、高选择性的催化材料的开发一直是材料和催化领域研究的热点。UiO-66(University of Oslo,UiO)作为一种具有...通过二氧化碳(CO_(2))与环氧化物的环加成反应可以将温室气体CO_(2)转化为有价值的化工产品环状碳酸酯,因而对该反应具有高效、高选择性的催化材料的开发一直是材料和催化领域研究的热点。UiO-66(University of Oslo,UiO)作为一种具有较高稳定性、较大开放性孔道的金属有机骨架材料(metal-organic framework,MOFs),在催化领域一直作为催化材料被广泛研究,但对于Lewis酸、碱催化的CO_(2)环加成反应,UiO-66通常需要在较为苛刻的反应条件下,或在离子液体类助催化剂或溶剂存在时才能展示出一定的催化效果。通过引入功能性基团、离子液体功能化、制造缺陷和与其他材料复合等手段可增加UiO-66框架的酸、碱位点含量,从而有效提高材料对CO_(2)环加成反应的催化性能。展开更多
基金supported by National Key R&D Program of China(2016YFB0901600)the National Natural Science Foundation of China(51772313 , U1830113 and 51802334)
文摘Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh kg-1). The commercialization of Li–S batteries is impeded by several key challenges at cathode side, e.g. the insulating nature of sulfur and discharged products(Li2S 2 and Li2S), the solubility of long-chain polysulfides and volume variation of sulfur cathode upon cycling. Recently, the carbonbased derivatives from metal-organic frameworks(MOFs) has emerged talent in their utilization as cathode hosts for Li–S batteries. They are not only highly conductive and porous to enable the acceleration of Li +/e-transfer and accommodation of volumetric expansion of sulfur cathode during cycling, but also enriched by controllable chemical active sites to enable the adsorption of polysulfides and promotion of their conversion reaction kinetics. In this review, based on the types of MOFs(e.g. ZIF-8, ZIF-67, Prussian blue, Al-MOF, MOF-5, Cu-MOF, Ni-MOF), the synthetic methods, formation process and morphology, structural superiority of MOFs-derived carbon frameworks along with their electrochemical performance as cathode host in Li–S batteries are summarized and discussed.
基金supported by the National Natural Science Foundation of China (Grant Nos. 21671085, 21701063)the Jiangsu Province Science Foundation for Youths (BK20150237)+1 种基金the Natural Science Foundation of Jiangsu Province (BK20161160)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Porous structures o er highly accessible surfaces and rich pores, which facilitate the exposure of numerous active sites for photocatalytic reactions, leading to excellent performances. Recently, metal–organic frameworks(MOFs) have been considered ideal precursors for well-designed semiconductors with porous structures and/or heterostructures, which have shown enhanced photocatalytic activities. In this review, we summarize the recent development of porous structures, such as metal oxides and metal sulfides, and their heterostructures, derived from MOF-based materials as catalysts for various light-driven energy-/environment-related reactions, including water splitting, CO_2 reduction, organic redox reaction, and pollution degradation. A summary and outlook section is also included.
文摘Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and energy storage, because of their unique structures. In this paper, we prepared a metal-organic framework [(<em>μ</em><sub>2</sub>-2-methylimidazolyl)<sub>12</sub>-Zn(ii)<sub>6</sub>-H<sub>18</sub>O<sub>10</sub>]<sub>n</sub>(ZM) with well-developed pores and high specific surface area of MOFs by the solution method. And MOF-derived porous carbon was prepared by the direct charring method in an argon atmosphere using a mixture of ZM, ZM and potassium citrate as carbon precursors. Characterization analysis revealed that the maximum specific surface area of ZMPC-800-1:15 was 2014.97 m<sup>2</sup><span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, and the pore size structure was mainly mesoporous. At a current density of 1.0 A<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup> the specific capacitance of ZMC-800 and ZMPC-800-1:15 was 121.3 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup> and 226.6 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, respectively, with a substantial increase of 86.8%. The specific capacitance of ZMPC-800-1:15 decays to 168.8 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, with a decay rate of 25.5%, when the current density increases to 10.0 A<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>. After 5000 constant current charge/ discharge cycles, the capacitance retention rate was still 96.41%. These results prove that the application of MOF-derived carbon materials in future supercapacitors is very promising.
文摘通过二氧化碳(CO_(2))与环氧化物的环加成反应可以将温室气体CO_(2)转化为有价值的化工产品环状碳酸酯,因而对该反应具有高效、高选择性的催化材料的开发一直是材料和催化领域研究的热点。UiO-66(University of Oslo,UiO)作为一种具有较高稳定性、较大开放性孔道的金属有机骨架材料(metal-organic framework,MOFs),在催化领域一直作为催化材料被广泛研究,但对于Lewis酸、碱催化的CO_(2)环加成反应,UiO-66通常需要在较为苛刻的反应条件下,或在离子液体类助催化剂或溶剂存在时才能展示出一定的催化效果。通过引入功能性基团、离子液体功能化、制造缺陷和与其他材料复合等手段可增加UiO-66框架的酸、碱位点含量,从而有效提高材料对CO_(2)环加成反应的催化性能。
