due to 和 owing to 都是“由于”的意思。一般来说,owingto 通常在句中作状语,而 due to 则常在句中作定语和表语。但是,随着语言的发展,其用法也产生了一些变化,尤其是在现代英语中。下面笔者根据自己所见,初步作些探讨。一、owing to...due to 和 owing to 都是“由于”的意思。一般来说,owingto 通常在句中作状语,而 due to 则常在句中作定语和表语。但是,随着语言的发展,其用法也产生了一些变化,尤其是在现代英语中。下面笔者根据自己所见,初步作些探讨。一、owing to 在句中作原因状语。例如: 1.Owing to the fact that he was tired,he stopped tohave a rest. 2.Owing to repeated failures,he was almost dis-couraged.展开更多
Light-driven artificial molecular machines[1,2]are a class of functional small molecules powered by photochemical reactions,broadly divided into molecular motors and molecular photoswitches.Molecular motors[3,4],owing...Light-driven artificial molecular machines[1,2]are a class of functional small molecules powered by photochemical reactions,broadly divided into molecular motors and molecular photoswitches.Molecular motors[3,4],owing to their intrinsic point chirality and dynamic axial chirality,undergo unidirectional rotation about a carbon–carbon double bond when irradiated with light.In nature,biological molecular motors and pumps are ubiquitous:driving vision,intracellular transport,energy conversion,signal transduction,muscle contraction,and locomotion.展开更多
To the Editor:Liver resection,particularly anatomical hepatectomy,has become a vital surgical approach for managing a range of liver diseases[1].Owing to its deep anatomical position,the caudate lobe is frequently imp...To the Editor:Liver resection,particularly anatomical hepatectomy,has become a vital surgical approach for managing a range of liver diseases[1].Owing to its deep anatomical position,the caudate lobe is frequently implicated in hepatobiliary diseases,necessitating precise evaluation and targeted treatment during anatomical liver resection[2,3].The caudate lobe's vascular anatomy is complex:the left portal vein branch(G1L,LPb)primarily supplies the Spiegel lobe,the bifurcation branch(G1F,HBb)feeds the paracaval region or caudate process,and the right posterior portal branch(G1C,RPb)serves the caudate process[4,5].展开更多
owe 是动词,due 是形容词。但 owe to 和 be due to 都有“应归于”的意思。它们怎样使用?如何区别呢?1.owe to:本义是欠(某人)的债,既而表示“受到……的恩惠,感激……,对……负有义务,应该把……归功于……,靠……而……。”如:He ow...owe 是动词,due 是形容词。但 owe to 和 be due to 都有“应归于”的意思。它们怎样使用?如何区别呢?1.owe to:本义是欠(某人)的债,既而表示“受到……的恩惠,感激……,对……负有义务,应该把……归功于……,靠……而……。”如:He owes ￡50 to his tailor.他欠他的裁缝50镑。We owe a great deal to our parents and teachers.我们深受父母及师长之恩。She owes her wealth to hard work and good luck.她把她的富有归功于努力工作和好的运气。展开更多
Ni(0)nanoparticles(NPs)are unstable and tend to aggregate in water,which poses a considerable challenge in their catalytic application.To overcome these drawbacks,integrated Ni-noble metal bimetallic NPs with a hollow...Ni(0)nanoparticles(NPs)are unstable and tend to aggregate in water,which poses a considerable challenge in their catalytic application.To overcome these drawbacks,integrated Ni-noble metal bimetallic NPs with a hollow-structured support are expected to enhance performances in heterogeneous catalysis.Herein,we present a simple approach for facile fabrication of Ni NPs embedded in a carbon layer on raspberry-like SiO_(2) hollow nanocages with a hydrophobic surface(SiO_(2)@C-Ni).Owing to the high affinity between Ni and histine-rich protein,the resultant raspberry-like SiO_(2)@C-Ni composites exhibit good performance in the adsorption of His-rich protein.Moreover,by the galvanic replacement reaction between Ni and Pd2+,hollow structured SiO_(2)@C-PdNi composites are easily obtained,while endowing the SiO_(2)@C-PdNi composites with a hydrophilic surface,greatly beneficial for the catalysis reaction in the aqueous phase.More attractively,the synthetic strategy could be extended to the synthesis of other Nibased bimetallic alloy NPs,such as SiO_(2)@C-AgNi and SiO_(2)@C-AuNi composites.This work highlights the superiority of transition metal ion mediated RF chemistry,the sol–gel process and emulsifier-free polymerization in the ingenious design of hollow structured materials embedded with well-dispersed metal alloy NPs.展开更多
Sluggish redox kinetics and the polysulfide shuttle effect hinder the commercialization of lithium–sulfur batteries.Herein,we report an in situ combination of BiOX(X=F,Cl,Br,and I)and rGO that forms an ultrathin laye...Sluggish redox kinetics and the polysulfide shuttle effect hinder the commercialization of lithium–sulfur batteries.Herein,we report an in situ combination of BiOX(X=F,Cl,Br,and I)and rGO that forms an ultrathin layered structure BiOX/rGO as a sulfur host.Polar BiOX,with alternating X−and[Bi2O22−]layers,strongly adsorbs lithium polysulfides(LiPSs)owing to the high electronegativity of X and O atoms,which reduces the electron density of Bi.This results in the empty orbitals of Bi providing more Lewis acid sites for accepting external electrons from LiPSs,thus accelerating the redox kinetics of sulfur.The BiOF/rGO-S cathode delivers a high capacity of 997 mA h g^(−1) over 400 cycles at 0.5 C.Even with a high sulfur loading of 9.1 mg cm^(-2) and an E/S ratio of 7.7μL mg^(−1),it retains a capacity of 628.8 mA h g^(−1) after 90 cycles at 0.1 C.In situ studies and DFT calculations reveal that BiOF/rGO promotes the SRR process and inhibits the polysulfide shuttle effect.This work elucidates the correlation between the electron cloud density of Bi in BiOX and the electrocatalytic performances of lithium–sulfur batteries and the underlying mechanisms,providing novel insights for designing high-performance sulfur host materials.展开更多
In this work,novel Ni_(3)Se_(2)nanowires are synthesized in situ on the surface of nickel foam(Ni_(3)Se_(2)NWs@NF)through a one-step hydrothermal reaction under different reaction times,and they demonstrate excellent ...In this work,novel Ni_(3)Se_(2)nanowires are synthesized in situ on the surface of nickel foam(Ni_(3)Se_(2)NWs@NF)through a one-step hydrothermal reaction under different reaction times,and they demonstrate excellent energy storage performance for hybrid supercapacitors(HSCs).Owing to their good electron transfer capability and porous and hierarchical architecture,the as-prepared Ni_(3)Se_(2)NWs@NF shows a high capacity of 2.6 C cm^(−2)at 5 mA cm^(−2)in a three-electrode cell.Even if the current density increases up to 250 mA cm^(−2),its specific capacity still remains at 0.93 C cm^(−2),exhibiting excellent rate capability.Furthermore,an HSC was assembled with the as-prepared Ni_(3)Se_(2)NWs@NF as the positive electrode and activated carbon(AC)as the negative electrode,in 2 M KOH aqueous electrolyte.The Ni_(3)Se_(2)NWs@NF//AC HSC demonstrates a high energy density of 64.4 W h kg^(−1)at a power density of 446.8 W kg^(−1)at 0.43 A g^(−1)with an extended voltage of 1.6 V,along with outstanding long-term cycling stability that retains 93.9%of the initial capacity after 10000 cycles.To the best of our knowledge,the Ni_(3)Se_(2)NWs@NF//AC HSC developed in this work demonstrates the best capacity performance among the reported HSCs with nickel selenides as electrode materials in aqueous electrolytes.Our results manifest that the Ni_(3)Se_(2)NWs@NF is a promising electrode material for high-performance HSCs.展开更多
NiFe-based catalysts are expected to replace commercially available noble metal-based electrocatalysts for the oxygen evolution reaction(OER)owing to their reconfigurability into high-performance NiFe oxyhydroxides fr...NiFe-based catalysts are expected to replace commercially available noble metal-based electrocatalysts for the oxygen evolution reaction(OER)owing to their reconfigurability into high-performance NiFe oxyhydroxides from their phosphides.However,how to rapidly reconstruct NiFe phosphides into oxyhydroxides for efficient water oxidation remains a challenge in this field.In this work,we proposed an in situ acid corroding-phosphating strategy to build a Fe-rich layer-coated NiFe phosphide electrocatalyst on NiFe foam(o-NiFeP/NFF).Our uniquely synthesized o-NiFeP/NFF delivers an extremely low overpotential of 224 mV to achieve 100 mA cm^(−2) and holds∼320 mA cm^(−2) at an overpotential of 427 mV for 468 h without degeneration,demonstrating excellent activity and stability in the OER.Acid corrosion not only facilitates the immediate conversion of phosphides to oxyhydroxides in alkaline electrolytes,but also increases the surface Fe/Ni atomic ratio,thereby significantly enhancing water oxidation activity.Moreover,the monolithic nature between a electrocatalyst and a conductive substrate substantially enhances the stability of the catalyst,which was achieved by obtaining the metal ions in the electrocatalyst through acid etching of the conductive substrate.This work not only constructs a highly reconfigurable electrocatalyst,but also proposes a straightforward and universal strategy to fabricate durable OER electrocatalysts.展开更多
Porous organic polymers(POPs)are promising candidates for catalyzing the hydrogen evolution reaction(HER)and the oxygen reduction reaction(ORR)owing to their tunable porous structures and abundant chemical reaction ch...Porous organic polymers(POPs)are promising candidates for catalyzing the hydrogen evolution reaction(HER)and the oxygen reduction reaction(ORR)owing to their tunable porous structures and abundant chemical reaction channels/active centers.However,insufficient conductivities limit their practical applications in the HER/ORR.The challenge is to construct conductive POPs with highly efficient HER/ORR performance.Herein,a series of metal-free corrole-based donor–acceptor POPs(Cor-D–A-POPs)as bifunctional HER/ORR catalysts have been designed and constructed from 5,10,15-tris(p-aminophenyl)corrole(TPAPC)and 2,2’-bithiophene-5,5’-dialdehyde(BTDA)or 2,5-thiophenedialdehyde(TDA)with a donor–acceptor method.Compared with Cor-D–A-POPs using TDA as an electron donor(Cor-TDA-D–A-POPs),Cor-D–A-POPs using BTDA as an electron donor(Cor-BTDA-D–A-POPs)exhibit higher HER/ORR activities due to their more favorable charge transfer ability from the BTDA donor to the TPAPC acceptor.The integration of high surface area,rich accessible catalytic sites,and high conductivity makes Cor-BTDA-D–A-POP-1 constructed in a mixed solvent of n-butanol/mesitylene(1:1)exhibit optimal HER/ORR activities in alkaline solution,with a comparable HER overpotential of 0.10 V at 10 mA cm^(−2)and an ORR Tafel slope of 90.0 mV dec−1 to Pt/C(0.09 V and 88.0 mV dec^(−1)).Moreover,its HER/ORR stability is superior to that of Pt/C.The experimental results are consistent with density functional theory calculations.Therefore,the combination of suitable electron donors and electron acceptors can promote charge transfer within POPs and generate high activities for the HER/ORR.展开更多
Li_(2)FeSiO_(4)is a superior cathode material for lithium ion batteries(LIBs)owing to its high capacity,low cost,and superior stability.Exhilaratingly,the material also exhibits the desired electrochemical performance...Li_(2)FeSiO_(4)is a superior cathode material for lithium ion batteries(LIBs)owing to its high capacity,low cost,and superior stability.Exhilaratingly,the material also exhibits the desired electrochemical performance as the anode for LIBs in comparison with traditional carbon materials.However,the Li_(2)FeSiO_(4)anode is subject to a fatal capacity degradation in long cycles,due to its low conductivity and serious particle agglomeration.展开更多
Potassium ion batteries(PIBs)are important for the development of energy storage systems as an effective complement to lithium ion batteries(LIBs)owing to the abundance of potassium resources in the earth’s crust to ...Potassium ion batteries(PIBs)are important for the development of energy storage systems as an effective complement to lithium ion batteries(LIBs)owing to the abundance of potassium resources in the earth’s crust to meet the needs of large-scale energy storage systems.To this end,numerous studies have focused on anode materials,which can provide high capacity for PIBs.Bimetallic-based compounds(ABXs)achieve higher capacity and structural diversity due to their different chemical compositions and rich spatial structures.Moreover,the synergistic effect of the two metals makes the structure of ABXs more stable.Hence,ABXs are one of the most promising anode materials.This review focuses on performance optimization strategies(such as metal base selection,structural design,voltage regulation,and electrolyte optimization)and the electrochemical properties of ABXs.Finally,the current challenges and research prospectives of ABXs are presented.This review is expected to provide new perspectives and deeper insights into the study of ABXs as anode materials for PIBs and large-scale energy storage devices.展开更多
A novel unique popcorn-like three-dimensional(3D)hierarchical structural electrocatalyst is synthesized by the pyrolysis of ZIF-8/ZIF-67 and polyacrylonitrile fiber composites,where popcorn-like Co_(3)O_(4) nanopartic...A novel unique popcorn-like three-dimensional(3D)hierarchical structural electrocatalyst is synthesized by the pyrolysis of ZIF-8/ZIF-67 and polyacrylonitrile fiber composites,where popcorn-like Co_(3)O_(4) nanoparticles coated with nitrogen-doped amorphous carbon anchor onto the tips of N-doped carbon nanotubes(NCNTs),and the NCNTs grow on carbon nanofiber(NAC@Co_(3)O_(4)/NCNTs/CNF).Owing to the positive synergistic effects of 3D hierarchical NCNT networks and popcorn-like Co_(3)O_(4) species,NAC@Co_(3)O_(4)/NCNTs/CNF shows a record outstanding hydrogen evolution reaction performance(HER;the overpotential at 10 mA cm^(-2) is just 76 mV)and wonderful stability for the oxygen reduction reaction(ORR;73%retention of initial ORR activity after 70 h).Density functional theory(DFT)calculations demonstrate that the chemical interaction between the popcorn-like Co_(3)O_(4) species and NCNTs benefit the chemisorption of hydrogen and oxygen-containing intermediates,thus accelerating the performance of ORR,OER,and HER.Furthermore,we assembled NAC@Co_(3)O_(4)/NCNTs/CNF as a rechargeable Zn-air battery and an overall water splitting device,displaying a maximum power density of 267.58 mW cm^(-2) and almost 100%faradaic efficiency,which provides a promising prospect for surpassing traditional trifunctional electrocatalysts.It is expected that this finding will offer a new concept for synthesizing highly efficient trifunctional materials and applications.展开更多
To the Editor:The hemivertebra is an unusual but not rare spinal deformity,which could result in progressive congenital scoliosis(CS).Owing to its poor response to brace treatment,early surgical intervention is usuall...To the Editor:The hemivertebra is an unusual but not rare spinal deformity,which could result in progressive congenital scoliosis(CS).Owing to its poor response to brace treatment,early surgical intervention is usually required for correcting deformity and preventing curve progression.[1]Hemivertebra resection has been proved to be an effective surgical treatment for CS secondary to hemivertebra.The best indication is isolated hemivertebra in young children.[2]Unfortunately,some CS patients,especially in the rural areas,remain under-diagnosed and untreated until reaching their adolescence.展开更多
Zeolites,as a class of porous inorganic materials,are extensively employed across a range of industrial applications,including catalysis[1],and adsorption separation[2],owing to their exceptional thermal stability,hig...Zeolites,as a class of porous inorganic materials,are extensively employed across a range of industrial applications,including catalysis[1],and adsorption separation[2],owing to their exceptional thermal stability,highly ordered pore structures,and tunable acidic properties.These characteristics enable zeolites to perform with remarkable efficiency and versatility in various processes.However,in the commonly employed aluminosilicate zeolites,Al atoms,acting as the active centers of acidity.展开更多
文摘due to 和 owing to 都是“由于”的意思。一般来说,owingto 通常在句中作状语,而 due to 则常在句中作定语和表语。但是,随着语言的发展,其用法也产生了一些变化,尤其是在现代英语中。下面笔者根据自己所见,初步作些探讨。一、owing to 在句中作原因状语。例如: 1.Owing to the fact that he was tired,he stopped tohave a rest. 2.Owing to repeated failures,he was almost dis-couraged.
文摘Light-driven artificial molecular machines[1,2]are a class of functional small molecules powered by photochemical reactions,broadly divided into molecular motors and molecular photoswitches.Molecular motors[3,4],owing to their intrinsic point chirality and dynamic axial chirality,undergo unidirectional rotation about a carbon–carbon double bond when irradiated with light.In nature,biological molecular motors and pumps are ubiquitous:driving vision,intracellular transport,energy conversion,signal transduction,muscle contraction,and locomotion.
基金supported by the grants from the Natural Science Foundation of China(82173129 and 82203330)China Post-doctoral Science Foundation(2022M711589)+1 种基金Distinguished Youth Project of Nanjing Drum Tower HospitalNanjing Health Science and Technology Development Project(YKK22065)。
文摘To the Editor:Liver resection,particularly anatomical hepatectomy,has become a vital surgical approach for managing a range of liver diseases[1].Owing to its deep anatomical position,the caudate lobe is frequently implicated in hepatobiliary diseases,necessitating precise evaluation and targeted treatment during anatomical liver resection[2,3].The caudate lobe's vascular anatomy is complex:the left portal vein branch(G1L,LPb)primarily supplies the Spiegel lobe,the bifurcation branch(G1F,HBb)feeds the paracaval region or caudate process,and the right posterior portal branch(G1C,RPb)serves the caudate process[4,5].
文摘owe 是动词,due 是形容词。但 owe to 和 be due to 都有“应归于”的意思。它们怎样使用?如何区别呢?1.owe to:本义是欠(某人)的债,既而表示“受到……的恩惠,感激……,对……负有义务,应该把……归功于……,靠……而……。”如:He owes ￡50 to his tailor.他欠他的裁缝50镑。We owe a great deal to our parents and teachers.我们深受父母及师长之恩。She owes her wealth to hard work and good luck.她把她的富有归功于努力工作和好的运气。
基金the financial support provided by the Natural Science Foundation of Shanghai City(18ZR1416400)the Fundamental Research Funds for the Central Universities(PA2020GDKC0005)the National Key R&D Program of China(no.2018YFC1801503).
文摘Ni(0)nanoparticles(NPs)are unstable and tend to aggregate in water,which poses a considerable challenge in their catalytic application.To overcome these drawbacks,integrated Ni-noble metal bimetallic NPs with a hollow-structured support are expected to enhance performances in heterogeneous catalysis.Herein,we present a simple approach for facile fabrication of Ni NPs embedded in a carbon layer on raspberry-like SiO_(2) hollow nanocages with a hydrophobic surface(SiO_(2)@C-Ni).Owing to the high affinity between Ni and histine-rich protein,the resultant raspberry-like SiO_(2)@C-Ni composites exhibit good performance in the adsorption of His-rich protein.Moreover,by the galvanic replacement reaction between Ni and Pd2+,hollow structured SiO_(2)@C-PdNi composites are easily obtained,while endowing the SiO_(2)@C-PdNi composites with a hydrophilic surface,greatly beneficial for the catalysis reaction in the aqueous phase.More attractively,the synthetic strategy could be extended to the synthesis of other Nibased bimetallic alloy NPs,such as SiO_(2)@C-AgNi and SiO_(2)@C-AuNi composites.This work highlights the superiority of transition metal ion mediated RF chemistry,the sol–gel process and emulsifier-free polymerization in the ingenious design of hollow structured materials embedded with well-dispersed metal alloy NPs.
基金support from the National Natural Science Foundation of China(No.21373189)the Science and Technology Department of Henan Province(No.242102240001)+1 种基金the Fund of Longzihu New Energy Laboratory(No.LZGLH2023011)the Top-Notch Talents Program of Henan Agricultural University(No.30501035).
文摘Sluggish redox kinetics and the polysulfide shuttle effect hinder the commercialization of lithium–sulfur batteries.Herein,we report an in situ combination of BiOX(X=F,Cl,Br,and I)and rGO that forms an ultrathin layered structure BiOX/rGO as a sulfur host.Polar BiOX,with alternating X−and[Bi2O22−]layers,strongly adsorbs lithium polysulfides(LiPSs)owing to the high electronegativity of X and O atoms,which reduces the electron density of Bi.This results in the empty orbitals of Bi providing more Lewis acid sites for accepting external electrons from LiPSs,thus accelerating the redox kinetics of sulfur.The BiOF/rGO-S cathode delivers a high capacity of 997 mA h g^(−1) over 400 cycles at 0.5 C.Even with a high sulfur loading of 9.1 mg cm^(-2) and an E/S ratio of 7.7μL mg^(−1),it retains a capacity of 628.8 mA h g^(−1) after 90 cycles at 0.1 C.In situ studies and DFT calculations reveal that BiOF/rGO promotes the SRR process and inhibits the polysulfide shuttle effect.This work elucidates the correlation between the electron cloud density of Bi in BiOX and the electrocatalytic performances of lithium–sulfur batteries and the underlying mechanisms,providing novel insights for designing high-performance sulfur host materials.
基金supported by the Education Department of Henan Province(20A150037 and 18A430003)the Scientific and Technological Project of Henan Province,the Scientific Project of Xuchang University(2018ZD005)+3 种基金National Natural Science Foundation of China(51772238,41372055,51502229,11474357,11804289 and 51902281)the CSS project(YK2015-0602006)the Fundamental Research Funds for the Central Universities and the World-Class Universities(Disciplines)the Characteristic Development Guidance Funds for the Central Universities.
文摘In this work,novel Ni_(3)Se_(2)nanowires are synthesized in situ on the surface of nickel foam(Ni_(3)Se_(2)NWs@NF)through a one-step hydrothermal reaction under different reaction times,and they demonstrate excellent energy storage performance for hybrid supercapacitors(HSCs).Owing to their good electron transfer capability and porous and hierarchical architecture,the as-prepared Ni_(3)Se_(2)NWs@NF shows a high capacity of 2.6 C cm^(−2)at 5 mA cm^(−2)in a three-electrode cell.Even if the current density increases up to 250 mA cm^(−2),its specific capacity still remains at 0.93 C cm^(−2),exhibiting excellent rate capability.Furthermore,an HSC was assembled with the as-prepared Ni_(3)Se_(2)NWs@NF as the positive electrode and activated carbon(AC)as the negative electrode,in 2 M KOH aqueous electrolyte.The Ni_(3)Se_(2)NWs@NF//AC HSC demonstrates a high energy density of 64.4 W h kg^(−1)at a power density of 446.8 W kg^(−1)at 0.43 A g^(−1)with an extended voltage of 1.6 V,along with outstanding long-term cycling stability that retains 93.9%of the initial capacity after 10000 cycles.To the best of our knowledge,the Ni_(3)Se_(2)NWs@NF//AC HSC developed in this work demonstrates the best capacity performance among the reported HSCs with nickel selenides as electrode materials in aqueous electrolytes.Our results manifest that the Ni_(3)Se_(2)NWs@NF is a promising electrode material for high-performance HSCs.
基金support from the National Natural Science Foundation of China(12074435 and 52001335).
文摘NiFe-based catalysts are expected to replace commercially available noble metal-based electrocatalysts for the oxygen evolution reaction(OER)owing to their reconfigurability into high-performance NiFe oxyhydroxides from their phosphides.However,how to rapidly reconstruct NiFe phosphides into oxyhydroxides for efficient water oxidation remains a challenge in this field.In this work,we proposed an in situ acid corroding-phosphating strategy to build a Fe-rich layer-coated NiFe phosphide electrocatalyst on NiFe foam(o-NiFeP/NFF).Our uniquely synthesized o-NiFeP/NFF delivers an extremely low overpotential of 224 mV to achieve 100 mA cm^(−2) and holds∼320 mA cm^(−2) at an overpotential of 427 mV for 468 h without degeneration,demonstrating excellent activity and stability in the OER.Acid corrosion not only facilitates the immediate conversion of phosphides to oxyhydroxides in alkaline electrolytes,but also increases the surface Fe/Ni atomic ratio,thereby significantly enhancing water oxidation activity.Moreover,the monolithic nature between a electrocatalyst and a conductive substrate substantially enhances the stability of the catalyst,which was achieved by obtaining the metal ions in the electrocatalyst through acid etching of the conductive substrate.This work not only constructs a highly reconfigurable electrocatalyst,but also proposes a straightforward and universal strategy to fabricate durable OER electrocatalysts.
基金supported by the National Natural Science Foundation of China(Grant No.52271251)the Henan Provincial Science and Technology Research Project(Grant No.222102230050)the Doctoral Startup Fund of Xinxiang Medical University(Grant No.XYBSKYZZ201507).
文摘Porous organic polymers(POPs)are promising candidates for catalyzing the hydrogen evolution reaction(HER)and the oxygen reduction reaction(ORR)owing to their tunable porous structures and abundant chemical reaction channels/active centers.However,insufficient conductivities limit their practical applications in the HER/ORR.The challenge is to construct conductive POPs with highly efficient HER/ORR performance.Herein,a series of metal-free corrole-based donor–acceptor POPs(Cor-D–A-POPs)as bifunctional HER/ORR catalysts have been designed and constructed from 5,10,15-tris(p-aminophenyl)corrole(TPAPC)and 2,2’-bithiophene-5,5’-dialdehyde(BTDA)or 2,5-thiophenedialdehyde(TDA)with a donor–acceptor method.Compared with Cor-D–A-POPs using TDA as an electron donor(Cor-TDA-D–A-POPs),Cor-D–A-POPs using BTDA as an electron donor(Cor-BTDA-D–A-POPs)exhibit higher HER/ORR activities due to their more favorable charge transfer ability from the BTDA donor to the TPAPC acceptor.The integration of high surface area,rich accessible catalytic sites,and high conductivity makes Cor-BTDA-D–A-POP-1 constructed in a mixed solvent of n-butanol/mesitylene(1:1)exhibit optimal HER/ORR activities in alkaline solution,with a comparable HER overpotential of 0.10 V at 10 mA cm^(−2)and an ORR Tafel slope of 90.0 mV dec−1 to Pt/C(0.09 V and 88.0 mV dec^(−1)).Moreover,its HER/ORR stability is superior to that of Pt/C.The experimental results are consistent with density functional theory calculations.Therefore,the combination of suitable electron donors and electron acceptors can promote charge transfer within POPs and generate high activities for the HER/ORR.
基金supported by the National Natural Science Foundation of China(51672235 and 51902277)the Xinjiang University Doctoral Research Foundation(2018),the Xinjiang Tianchi Doctoral Project(2018),the Natural Science Foundation of Xinjiang Uygur Autonomous Region of China(2019D01C044),and the National Ten Thousand Talents Program(2017).
文摘Li_(2)FeSiO_(4)is a superior cathode material for lithium ion batteries(LIBs)owing to its high capacity,low cost,and superior stability.Exhilaratingly,the material also exhibits the desired electrochemical performance as the anode for LIBs in comparison with traditional carbon materials.However,the Li_(2)FeSiO_(4)anode is subject to a fatal capacity degradation in long cycles,due to its low conductivity and serious particle agglomeration.
基金supported by the National Natural Science Foundation of China(22076116)the Sino-German Center for Research Promotion(GZ1579).
文摘Potassium ion batteries(PIBs)are important for the development of energy storage systems as an effective complement to lithium ion batteries(LIBs)owing to the abundance of potassium resources in the earth’s crust to meet the needs of large-scale energy storage systems.To this end,numerous studies have focused on anode materials,which can provide high capacity for PIBs.Bimetallic-based compounds(ABXs)achieve higher capacity and structural diversity due to their different chemical compositions and rich spatial structures.Moreover,the synergistic effect of the two metals makes the structure of ABXs more stable.Hence,ABXs are one of the most promising anode materials.This review focuses on performance optimization strategies(such as metal base selection,structural design,voltage regulation,and electrolyte optimization)and the electrochemical properties of ABXs.Finally,the current challenges and research prospectives of ABXs are presented.This review is expected to provide new perspectives and deeper insights into the study of ABXs as anode materials for PIBs and large-scale energy storage devices.
基金supported by the National Natural Science Foundation of China(NSFC)(Grants 51772073,51762013)the Key Project of Hebei Natural Science Foundation(E2020201030)+3 种基金the Beijing-Tianjin-Hebei Collaborative Innovation Community Construction Project(21344301D)the Second Batch of Young Talent of Hebei Province(No.70280016160250,No.70280011808)the Key Fund in Hebei Province Department of Education China(ZD2021014)the Central Government Guide Local Funding Projects for Scientific and Technological Development(216Z4404G).
文摘A novel unique popcorn-like three-dimensional(3D)hierarchical structural electrocatalyst is synthesized by the pyrolysis of ZIF-8/ZIF-67 and polyacrylonitrile fiber composites,where popcorn-like Co_(3)O_(4) nanoparticles coated with nitrogen-doped amorphous carbon anchor onto the tips of N-doped carbon nanotubes(NCNTs),and the NCNTs grow on carbon nanofiber(NAC@Co_(3)O_(4)/NCNTs/CNF).Owing to the positive synergistic effects of 3D hierarchical NCNT networks and popcorn-like Co_(3)O_(4) species,NAC@Co_(3)O_(4)/NCNTs/CNF shows a record outstanding hydrogen evolution reaction performance(HER;the overpotential at 10 mA cm^(-2) is just 76 mV)and wonderful stability for the oxygen reduction reaction(ORR;73%retention of initial ORR activity after 70 h).Density functional theory(DFT)calculations demonstrate that the chemical interaction between the popcorn-like Co_(3)O_(4) species and NCNTs benefit the chemisorption of hydrogen and oxygen-containing intermediates,thus accelerating the performance of ORR,OER,and HER.Furthermore,we assembled NAC@Co_(3)O_(4)/NCNTs/CNF as a rechargeable Zn-air battery and an overall water splitting device,displaying a maximum power density of 267.58 mW cm^(-2) and almost 100%faradaic efficiency,which provides a promising prospect for surpassing traditional trifunctional electrocatalysts.It is expected that this finding will offer a new concept for synthesizing highly efficient trifunctional materials and applications.
基金This work was supported by grants from National Natural Science Foundation(Nos.81802216 and 82272573).
文摘To the Editor:The hemivertebra is an unusual but not rare spinal deformity,which could result in progressive congenital scoliosis(CS).Owing to its poor response to brace treatment,early surgical intervention is usually required for correcting deformity and preventing curve progression.[1]Hemivertebra resection has been proved to be an effective surgical treatment for CS secondary to hemivertebra.The best indication is isolated hemivertebra in young children.[2]Unfortunately,some CS patients,especially in the rural areas,remain under-diagnosed and untreated until reaching their adolescence.
文摘Zeolites,as a class of porous inorganic materials,are extensively employed across a range of industrial applications,including catalysis[1],and adsorption separation[2],owing to their exceptional thermal stability,highly ordered pore structures,and tunable acidic properties.These characteristics enable zeolites to perform with remarkable efficiency and versatility in various processes.However,in the commonly employed aluminosilicate zeolites,Al atoms,acting as the active centers of acidity.
