The simultaneous accumulation of photo-holes and the specific activation of substrates present a significant challenge in photo-oxidation.Herein,we propose a dual-channel collaborative catalytic platform based on holl...The simultaneous accumulation of photo-holes and the specific activation of substrates present a significant challenge in photo-oxidation.Herein,we propose a dual-channel collaborative catalytic platform based on hollow TiO_(2) microspheres,using Cu single-atom(SA)catalysts and a composite polymer chain,to create separating pathways for unidirectional photogenerated electron/hole extraction.Ferrocene-functionalized graphene quantum dots are incorporated within the polymer chain for driving benzylamine(BA)oxidation.Quasi in situ transient photovoltage and femtosecond transient absorption tests reveal that leveraging the ultrafast charge separation capability of Cu SAs(0.44 ps)not only accelerates hole transport kinetics but also induces requisite Lewis acidity for the adsorption and activation of BA.In an air atmosphere,the rate of imine production reaches 4.81 mmol g^(−1) h^(−1)(selectivity of 98%).This study demonstrates the rational design of an SA/polymer chain dual-driven catalytic platform for optimizing kinetics and precisely controlling photocatalytic transformations in organic chemistry.展开更多
Manganese-based cathode materials are promising candidates for aqueous zinc ion batteries(AZIBs)by reason of their low cost and high energy density.However,their practical applicability is hampered by the intrinsic de...Manganese-based cathode materials are promising candidates for aqueous zinc ion batteries(AZIBs)by reason of their low cost and high energy density.However,their practical applicability is hampered by the intrinsic defects of poor electrical conductivity,sluggish reaction kinetics,and severe structural deterioration.Herein,we constructed a hierarchically porous structure composed of carbon-encapsulated Mn O nanoparticles(MOC)and three-dimensional(3D)nitrogen-doped graphene aerogel(NGA)(denoted as MOC@NGA).The hybrid was synthesized by a facile in-situ coprecipitation and annealing of manganesebased metal-organic framework(Mn-MOF74)and NGA composite(Mn-MOF74@NGA).Specifically,the carbon shells inherited from organic ligand of Mn-MOF74 could restrain the volume changes of Mn O,and the porous NGA prevented the agglomeration of MOC nanoparticles and enriched the types of interfacial chemical bonds.Profiting from the synergistic effect of rich interface chemical bonds and dual-carbon protection,the MOC@NGA hybrids exhibit fast interfacial electron/charge transfer and transport,and outstanding structural stability.Therefore,MOC@NGA cathode delivers an excellent rate performance(270 and 99.8 m Ah g^(-1)at 0.1 and 2.0 A g^(-1))and maintains an excellent specific capacity of 151.6 m Ah g^(-1)after 2,000cycles at 1.0 A g^(-1).Moreover,the fabricated MOC@NGA-based quasi-solid-state battery not only achieves outstanding flexibility but also displays impressive cycling stability,demonstrating a promising potential for portable and flexible equipment.This work provides a feasible strategy for the fabrication of the bridging structure of manganese-based oxides and porous carbon matrix for high-specific capacity and durable AZIBs cathodes.展开更多
基金financial support provided by the National Natural Science Foundation of China(No.22172057).
文摘The simultaneous accumulation of photo-holes and the specific activation of substrates present a significant challenge in photo-oxidation.Herein,we propose a dual-channel collaborative catalytic platform based on hollow TiO_(2) microspheres,using Cu single-atom(SA)catalysts and a composite polymer chain,to create separating pathways for unidirectional photogenerated electron/hole extraction.Ferrocene-functionalized graphene quantum dots are incorporated within the polymer chain for driving benzylamine(BA)oxidation.Quasi in situ transient photovoltage and femtosecond transient absorption tests reveal that leveraging the ultrafast charge separation capability of Cu SAs(0.44 ps)not only accelerates hole transport kinetics but also induces requisite Lewis acidity for the adsorption and activation of BA.In an air atmosphere,the rate of imine production reaches 4.81 mmol g^(−1) h^(−1)(selectivity of 98%).This study demonstrates the rational design of an SA/polymer chain dual-driven catalytic platform for optimizing kinetics and precisely controlling photocatalytic transformations in organic chemistry.
基金supported by the National Natural Science Foundation of China(22271114,21621001)the Foundation of Science and Technology Development of Jilin Province,China(20200801004GH)+1 种基金111 Project(B17020)the financial support by the program for JLU Science and Technology Innovative Research Team(JLUSTIRT)。
文摘Manganese-based cathode materials are promising candidates for aqueous zinc ion batteries(AZIBs)by reason of their low cost and high energy density.However,their practical applicability is hampered by the intrinsic defects of poor electrical conductivity,sluggish reaction kinetics,and severe structural deterioration.Herein,we constructed a hierarchically porous structure composed of carbon-encapsulated Mn O nanoparticles(MOC)and three-dimensional(3D)nitrogen-doped graphene aerogel(NGA)(denoted as MOC@NGA).The hybrid was synthesized by a facile in-situ coprecipitation and annealing of manganesebased metal-organic framework(Mn-MOF74)and NGA composite(Mn-MOF74@NGA).Specifically,the carbon shells inherited from organic ligand of Mn-MOF74 could restrain the volume changes of Mn O,and the porous NGA prevented the agglomeration of MOC nanoparticles and enriched the types of interfacial chemical bonds.Profiting from the synergistic effect of rich interface chemical bonds and dual-carbon protection,the MOC@NGA hybrids exhibit fast interfacial electron/charge transfer and transport,and outstanding structural stability.Therefore,MOC@NGA cathode delivers an excellent rate performance(270 and 99.8 m Ah g^(-1)at 0.1 and 2.0 A g^(-1))and maintains an excellent specific capacity of 151.6 m Ah g^(-1)after 2,000cycles at 1.0 A g^(-1).Moreover,the fabricated MOC@NGA-based quasi-solid-state battery not only achieves outstanding flexibility but also displays impressive cycling stability,demonstrating a promising potential for portable and flexible equipment.This work provides a feasible strategy for the fabrication of the bridging structure of manganese-based oxides and porous carbon matrix for high-specific capacity and durable AZIBs cathodes.
