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
In addition to their many well-known advantages(e.g.,ultra-high porosity,good pore size distribution,easy functionalization,and structural tolerability),metal-organic frameworks(MOFs)are a new class of advanced functi...In addition to their many well-known advantages(e.g.,ultra-high porosity,good pore size distribution,easy functionalization,and structural tolerability),metal-organic frameworks(MOFs)are a new class of advanced functional materials.However,their backbones are highly susceptible to deformation after exposure to acidic or alkaline conditions.As a result of lithium-ion batteries embedding or detaching directly from MOFs,they irreversibly collapse.As a result,they fail to maintain their electrochemical performance.These factors have hindered the development of MOFs as direct electrode materials,making the design of MOF materials with controlled morphology and stable dimensions a new challenge.In this study,we adopted a versatile and effective method to synthesize a novel MOF material(NiCo-BP(BP=BTC/phen and BTC=1,3,5-benzenetricarboxylic acid))using the rigid ligands 1,10-phenanthroline and homobenzotrizoic acid,and the emergence of the Ni-O/N and Co-O/N coordination layers was observed by extended X-ray absorption fine structure(EXAFS)tests,indicating that Ni and Co were coordinated with heterocyclic N-given atoms to form a stable p-πconjugated structure.Meanwhile,the metal-ion is attached to the carboxylic acid ligand on the other side,making the metal-organic skeleton complete and robust.The nanosphere structure of NiCo-BP(~400 nm)allows for full exposure and utilisation of the active sites,especially the Ni,Co,and phenanthroline units,and exhibit impressively high specific capacity and cycling stability.At a high current density of 1.0 A·g^(−1),a high discharge specific capacity of 631.6 mAh·g^(−1)was obtained after 1000 cycles.The co-participation of two organic ligands in the coordination is in accordance with the theory of soft and hard acids and bases,which contributes to the ability of the material to maintain a high capacity in cycling as well as its cyclic stability.展开更多
Metal-organic frameworks(MOFs)have favorable characteristics such as large specific surface area,high porosity,structural diversity,and pore surface modification,giving them great potential for development and attract...Metal-organic frameworks(MOFs)have favorable characteristics such as large specific surface area,high porosity,structural diversity,and pore surface modification,giving them great potential for development and attractive prospects in the research area of modern materials electrocatalysis.However,unsatisfactory catalytic activity and poor electronic conductivity are the main challenges facing MOFs.This review focuses on MOF-based materials used in electrocatalysis,based on the types of catalytic reactions that have used MOF-based materials in recent years along with their applications,and also looks at some new electrocatalytic materials and their future development prospects.展开更多
Herbal extraction residues(HERs)cause serious environmental pollution and resource waste.In this study,a novel green route was designed for the comprehensive reutilization of all components in HERs,taking Magnolia off...Herbal extraction residues(HERs)cause serious environmental pollution and resource waste.In this study,a novel green route was designed for the comprehensive reutilization of all components in HERs,taking Magnolia officinalis residues(MOR)as an example.The reluctant structure of MOR was first destroyed by alkali pretreatment to release the functional ingredients(magnolol and honokiol)originally remaining in MOR and to make MOR more accessible for hydrolysis.A metal–organic frame material MIL-101(Cr)with a maximum absorption capacity of 255.64 mg g^(-1)was synthesized to absorb the released honokiol and magnolol from the pretreated MOR solutions,and 40 g L^(-1)reducing sugars were obtained with 81.8%enzymatic hydrolysis rate at 10%MOR solid loading.Finally,382 mg L-1β-amyrin was produced from MOR hydrolysates by an engineered yeast strain.In total,1 kg honokiol,8 kg magnolol,and 7.64 kg β-amyrin could produce from 1 ton MOR by this cleaner process with a total economic output of 170,700 RMB.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National Natural Science Foundation of China(Nos.52071132,52261135632,U21A20284,and 52371237)Program for Innovative Team(in Science and Technology)in University of Henan Province,China(No.24IRTSTHN006)+3 种基金Natural Science Foundation of Henan,China(Nos.232300421080 and 222300420138)Science and Technology Project of Henan Province,China(Nos.232102241038 and 232102241004)Key Scientific Research Programs in Universities of Henan Province,China-Special Projects for Basic Research(No.23ZX008)Innovative Funds Plan of Henan University of Technology,China(No.2020ZKCJ04).
文摘In addition to their many well-known advantages(e.g.,ultra-high porosity,good pore size distribution,easy functionalization,and structural tolerability),metal-organic frameworks(MOFs)are a new class of advanced functional materials.However,their backbones are highly susceptible to deformation after exposure to acidic or alkaline conditions.As a result of lithium-ion batteries embedding or detaching directly from MOFs,they irreversibly collapse.As a result,they fail to maintain their electrochemical performance.These factors have hindered the development of MOFs as direct electrode materials,making the design of MOF materials with controlled morphology and stable dimensions a new challenge.In this study,we adopted a versatile and effective method to synthesize a novel MOF material(NiCo-BP(BP=BTC/phen and BTC=1,3,5-benzenetricarboxylic acid))using the rigid ligands 1,10-phenanthroline and homobenzotrizoic acid,and the emergence of the Ni-O/N and Co-O/N coordination layers was observed by extended X-ray absorption fine structure(EXAFS)tests,indicating that Ni and Co were coordinated with heterocyclic N-given atoms to form a stable p-πconjugated structure.Meanwhile,the metal-ion is attached to the carboxylic acid ligand on the other side,making the metal-organic skeleton complete and robust.The nanosphere structure of NiCo-BP(~400 nm)allows for full exposure and utilisation of the active sites,especially the Ni,Co,and phenanthroline units,and exhibit impressively high specific capacity and cycling stability.At a high current density of 1.0 A·g^(−1),a high discharge specific capacity of 631.6 mAh·g^(−1)was obtained after 1000 cycles.The co-participation of two organic ligands in the coordination is in accordance with the theory of soft and hard acids and bases,which contributes to the ability of the material to maintain a high capacity in cycling as well as its cyclic stability.
基金financially supported by the National Natural Science Foundation of China(Nos.21677010,51808037)the National Key R&D Program of China(No.2021YFB3500702)the Special Fund of Beijing Key Laboratory of Indoor Air Quality Evaluation and Control(No.BZ0344KF21-04)。
文摘Metal-organic frameworks(MOFs)have favorable characteristics such as large specific surface area,high porosity,structural diversity,and pore surface modification,giving them great potential for development and attractive prospects in the research area of modern materials electrocatalysis.However,unsatisfactory catalytic activity and poor electronic conductivity are the main challenges facing MOFs.This review focuses on MOF-based materials used in electrocatalysis,based on the types of catalytic reactions that have used MOF-based materials in recent years along with their applications,and also looks at some new electrocatalytic materials and their future development prospects.
基金supported by the National Key Research and Development Project(2019YFC1906601)China the Scientific and Technological Innovation Project of the Chinese Academy of Chinese Medical Sciences(C12021A04111)the Fundamental Research Funds for the Central Public Welfare Research Institutes(ZZ13-YQ-040).
文摘Herbal extraction residues(HERs)cause serious environmental pollution and resource waste.In this study,a novel green route was designed for the comprehensive reutilization of all components in HERs,taking Magnolia officinalis residues(MOR)as an example.The reluctant structure of MOR was first destroyed by alkali pretreatment to release the functional ingredients(magnolol and honokiol)originally remaining in MOR and to make MOR more accessible for hydrolysis.A metal–organic frame material MIL-101(Cr)with a maximum absorption capacity of 255.64 mg g^(-1)was synthesized to absorb the released honokiol and magnolol from the pretreated MOR solutions,and 40 g L^(-1)reducing sugars were obtained with 81.8%enzymatic hydrolysis rate at 10%MOR solid loading.Finally,382 mg L-1β-amyrin was produced from MOR hydrolysates by an engineered yeast strain.In total,1 kg honokiol,8 kg magnolol,and 7.64 kg β-amyrin could produce from 1 ton MOR by this cleaner process with a total economic output of 170,700 RMB.