Utilizing vacuum-tuned-atmosphere induced dip coating method,we achieve the cross-dimensional macroscopic diverse self-assemblies by using one building block with one chemical functionality.Coordinated modulating the ...Utilizing vacuum-tuned-atmosphere induced dip coating method,we achieve the cross-dimensional macroscopic diverse self-assemblies by using one building block with one chemical functionality.Coordinated modulating the vacuum degree,colloid concentration and evaporation atmosphere,Au@Ag core/shell nanocubes (NCs) can controllably assemble into diverse multi-dimensional superstructures.Under 0.08 MPa,we obtained the two-dimensional (2D) stepped superstructures with continuously tunable step width.In addition,we generated a series of tailorable nanoscale-roughened 2D Au@Ag NCs superstructures at 0.04 MPa,which exhibited the label-free ultrasensitive SERS detection for the different mutants of IAPP8-37 proteins.Under 0.01 MPa,we obtained the cross-dimensional tailorable Au@Ag NCs assemblies from random to macroscale 2D and three-dimensional (3D) densest superstructures by adjusting the capping ligand-environmental molecule interactions.This is a flexible method to generate as-prepared Au@Ag core/shell NCs into well-defined macroscopic diverse superstructures and to promote the exploitation into biological applications.展开更多
Developing highly efficient oxygen evolution reaction(OER)catalyst for the acidic corrosive operating conditions is a challenging task.Herein,we report the synthesis of uniform RuO_(2)clusters with~2 nm in size via el...Developing highly efficient oxygen evolution reaction(OER)catalyst for the acidic corrosive operating conditions is a challenging task.Herein,we report the synthesis of uniform RuO_(2)clusters with~2 nm in size via electrochemical leaching of Sr from SrRuO_(3) ceramic in acid.The RuO_(2)clusters exhibit ultrahigh OER activity with overpotential of~160 mV at 10 mA·cm_(geo)^(−2) in 1.0 M HClO4 solution for 30-h testing.The extended X-ray absorption fine structure measurement reveals enlarged Jahn-Teller distortion of Ru-O octahedra in the RuO_(2)clusters compared to its bulk counterpart.Density function theory calculations show that the enhanced Jahn-Teller distortion can improve the intrinsic OER activity of RuO_(2).展开更多
In this work, we present a new versatile strategy to prepare noble metal （Au, Ag and Cu） nanoclusters on TiO2 nanosheets in large scales with exposed （001） facets with controlled size, crystalline interface, and l...In this work, we present a new versatile strategy to prepare noble metal （Au, Ag and Cu） nanoclusters on TiO2 nanosheets in large scales with exposed （001） facets with controlled size, crystalline interface, and loading amount. By precise in situ calcination, the metal （M = Au, Ag, and Cu） nanocrystals with controllable size and better crystalline interface with the TiO2 support have been prepared. The potential application of the as-prepared Au, Ag, and Cu nanoclusters on TiO2 nanosheets as potential heterogeneous catalysts for organic synthesis, such as catalytic reduction of 4-nitrophenol to 4-aminophenol, has been demonstrated. After calcination, Au, Ag, and Cu nanocrystals were found to be proficient cocatalysts for photocatalytic H2 evolution, particularly the Au cocatalyst. Based on precise high-resolution transmission electron microscopy （HRTEM） and inductively coupled plasma optical emission spectrometry （ICP-OES） analyses, the flexible control of their size and loading amount as well as their intimate contact with the TiO2 nanosheet enhanced the photocatalytic H2 evolution activity and the sensitivity of the photocurrent response of the film. Furthermore, this aqueous-directed synthesis of metal nanoclusters on a support will generate further interest in the field of nanocatalysis.展开更多
This study reports the controllable surface roughening of Au-Ag alloy nanoplates via the galvanic replacement reaction between single-crystalline triangular Ag nanoplates and HAuC14 in an aqueous medium. With a combin...This study reports the controllable surface roughening of Au-Ag alloy nanoplates via the galvanic replacement reaction between single-crystalline triangular Ag nanoplates and HAuC14 in an aqueous medium. With a combination of experimental evidence and finite element method （FEM） simulations, improved electromagnetic field （E-field） enhancement around the surface-roughened Au- Ag nanoplates and tunable light absorption in the near-infrared （NIR） region （-800-1,400 nm） are achieved by the synergistic effects of the localized surface plasmon resonance （LSPR） from the maintained triangular shape, the controllable Au-Ag alloy composition, and the increased surface roughness. The NIR light extinction enables an active photothermal effect as well as a high photothermal conversion efficiency （78.5%）. The well-maintained triangular shape, surface- roughened evolutions of both micro- and nanostructures, and tunable NIR surface plasmon resonance effect enable potential applications of the Au-Ag alloy nanoplates in surface-enhanced Raman spectroscopic detection of biomolecules through 785-nm laser excitation.展开更多
Because of the intensified electrochemical activities,mixed metal oxides as a representative for pseudocapacitive materials play a key role for high performance supercapacitor electrodes.Nevertheless,low ion and elect...Because of the intensified electrochemical activities,mixed metal oxides as a representative for pseudocapacitive materials play a key role for high performance supercapacitor electrodes.Nevertheless,low ion and electron transfer rate and poor cycling performance in the electrode practically restrict further promotion of their electrochemical performance.In order to offset the defect,a novel copper(Cu)foamsupported nickel molybdate nanosheet decorated carbon nanotube wrapped copper oxide nanowire array(NiMoO4 NSs-CNTs-CuO NWAs/Cu foam)flexible electrode is constructed.The as-prepared electrode demonstrates a unique core-shell holey nanostructure with a large active surface area,which can provide a large number of active sites for redox reactions.Besides,the CNTs networks supply improved conductivity,which can hasten electron transport.Through this simple and efficient design method,the spatial distribution of each component in the flexible electrode is more orderly,short and fast electron transport path with low intrinsic resistance.As a result,the NiMoO4 NSs-CNTs-CuO NWAs/Cu foam as an adhesiveless supercapacitor electrode material exhibits excellent ene rgy storage perfo rmance with high specific areal capacitance of 23.40 F cm^(-2)at a current density of 2 mA cm^(-2),which outperforms most of the flexible electrodes re ported recently.The assembled asymmetric supercapacitor demonstrates an energy density up to 96.40 mW h cm^(-3)and a power density up to 0.4 W cm^(-3)under a working voltage window of 1.7 V.In addition,outstanding flexibility of up to 100°bend and good cycling stability with the capacitance retention of 82.53%after 10,000 cycles can be obtained.展开更多
Hydrogen energy is considered as an ideal energy with the advantages of green,sustainability,and high energy density,and water splitting is one of the efficient strategies for green hydrogen without carbon emission.As...Hydrogen energy is considered as an ideal energy with the advantages of green,sustainability,and high energy density,and water splitting is one of the efficient strategies for green hydrogen without carbon emission.As for cathodic hydrogen evolution reaction(HER),besides the Pt-based electrocatalysts with excellent electrocatalytic activities on HER,transition metal nitrides(TMNs)as cheap and facile-prepared electrocatalysts have shown remarkable electrocatalytic activities.Incorporation of N atom in metal interstitial lattice results in the unique structure of TMN with high electronic conductivity,strong chemical stability,and d-band contraction.Although the intrinsic electrocatalytic activities of TMNs are mostly lower than those of Pt,it also attracted much attention to the development of TMN with higher intrinsic activity by electronic structure modulation.Here,we review the recent improvement strategies for the intrinsic electrocatalytic activities of TMN catalysts on HER by electronic structure modulation,such as facet,alloying,doping,vacancy,heterostructure,and hybridization.Some important breakthroughs of TMNs have been made;however,the scale application of TMNs with high activity in commercial water electrolyzer is urgent to explore.The future development of TMNs is proposed to focus on developing facile synthesis methods,elucidating regulation mechanism and catalytic mechanism,and enhancing activity and stability.展开更多
基金the National Natural Science Foundation of China (Nos.51872030,51631001,21643003,51702016,and 51501010)Fundamental Research Funds for the Central Universities and Beijing Institute of Technology Research Fund Program for Young Scholars and ZDKT18-01 fund from State Key Laboratory of Explosion Science and Technology (Beijing Institute of Technology).We acknowledge critical and quantity of testing work supported by Beijing Zhongkebaice Technology Service Co., Ltd.
文摘Utilizing vacuum-tuned-atmosphere induced dip coating method,we achieve the cross-dimensional macroscopic diverse self-assemblies by using one building block with one chemical functionality.Coordinated modulating the vacuum degree,colloid concentration and evaporation atmosphere,Au@Ag core/shell nanocubes (NCs) can controllably assemble into diverse multi-dimensional superstructures.Under 0.08 MPa,we obtained the two-dimensional (2D) stepped superstructures with continuously tunable step width.In addition,we generated a series of tailorable nanoscale-roughened 2D Au@Ag NCs superstructures at 0.04 MPa,which exhibited the label-free ultrasensitive SERS detection for the different mutants of IAPP8-37 proteins.Under 0.01 MPa,we obtained the cross-dimensional tailorable Au@Ag NCs assemblies from random to macroscale 2D and three-dimensional (3D) densest superstructures by adjusting the capping ligand-environmental molecule interactions.This is a flexible method to generate as-prepared Au@Ag core/shell NCs into well-defined macroscopic diverse superstructures and to promote the exploitation into biological applications.
基金the National Natural Science Foundation of China(Nos.22022508,51602143 and 11874036)Guangdong Natural Science Foundation for Distinguished Young Scholars(No.2016A030306020)the National Key Research and Development Program of China(No.2017YFB0701600)。
文摘Developing highly efficient oxygen evolution reaction(OER)catalyst for the acidic corrosive operating conditions is a challenging task.Herein,we report the synthesis of uniform RuO_(2)clusters with~2 nm in size via electrochemical leaching of Sr from SrRuO_(3) ceramic in acid.The RuO_(2)clusters exhibit ultrahigh OER activity with overpotential of~160 mV at 10 mA·cm_(geo)^(−2) in 1.0 M HClO4 solution for 30-h testing.The extended X-ray absorption fine structure measurement reveals enlarged Jahn-Teller distortion of Ru-O octahedra in the RuO_(2)clusters compared to its bulk counterpart.Density function theory calculations show that the enhanced Jahn-Teller distortion can improve the intrinsic OER activity of RuO_(2).
文摘In this work, we present a new versatile strategy to prepare noble metal （Au, Ag and Cu） nanoclusters on TiO2 nanosheets in large scales with exposed （001） facets with controlled size, crystalline interface, and loading amount. By precise in situ calcination, the metal （M = Au, Ag, and Cu） nanocrystals with controllable size and better crystalline interface with the TiO2 support have been prepared. The potential application of the as-prepared Au, Ag, and Cu nanoclusters on TiO2 nanosheets as potential heterogeneous catalysts for organic synthesis, such as catalytic reduction of 4-nitrophenol to 4-aminophenol, has been demonstrated. After calcination, Au, Ag, and Cu nanocrystals were found to be proficient cocatalysts for photocatalytic H2 evolution, particularly the Au cocatalyst. Based on precise high-resolution transmission electron microscopy （HRTEM） and inductively coupled plasma optical emission spectrometry （ICP-OES） analyses, the flexible control of their size and loading amount as well as their intimate contact with the TiO2 nanosheet enhanced the photocatalytic H2 evolution activity and the sensitivity of the photocurrent response of the film. Furthermore, this aqueous-directed synthesis of metal nanoclusters on a support will generate further interest in the field of nanocatalysis.
基金This work was supported by the National Natural Science Foundation of China （Nos. 91323301, 21322105, and 51372025）, the Research Fund for the Doctoral Program of Higher Education of China （No. 2011101120016） and Program for New Century Excellent Talents in University （No. NCET-11-0793）. The authors would like to thank Prof. Chen Wang and Prof. Yanjun Guo of National Center for Nanoscience and Technology, China for AFM and SERS measure- ments and helpful discussions, respectively Dr. Haiwei Li for help on BET tests and helpful discussions.
文摘This study reports the controllable surface roughening of Au-Ag alloy nanoplates via the galvanic replacement reaction between single-crystalline triangular Ag nanoplates and HAuC14 in an aqueous medium. With a combination of experimental evidence and finite element method （FEM） simulations, improved electromagnetic field （E-field） enhancement around the surface-roughened Au- Ag nanoplates and tunable light absorption in the near-infrared （NIR） region （-800-1,400 nm） are achieved by the synergistic effects of the localized surface plasmon resonance （LSPR） from the maintained triangular shape, the controllable Au-Ag alloy composition, and the increased surface roughness. The NIR light extinction enables an active photothermal effect as well as a high photothermal conversion efficiency （78.5%）. The well-maintained triangular shape, surface- roughened evolutions of both micro- and nanostructures, and tunable NIR surface plasmon resonance effect enable potential applications of the Au-Ag alloy nanoplates in surface-enhanced Raman spectroscopic detection of biomolecules through 785-nm laser excitation.
基金supported by the National Natural Science Foundation of China(Nos.51673117,51973118,and 21805193)the Science and Technology Innovation Commission of Shenzhen(Nos.JCYJ20170818093832350,JCYJ20170818112409808,JSGG20170824112840518,JCYJ20180507184711069,JCYJ20170818100112531,JCYJ20170817094628397,and JCYJ20180305125319991)+1 种基金the Key-Area Research and Development Program of Guangdong Province(Nos.2019B010929002 and 2019B010941001)the China Postdoctoral Science Foundation(No.2019M650212)。
文摘Because of the intensified electrochemical activities,mixed metal oxides as a representative for pseudocapacitive materials play a key role for high performance supercapacitor electrodes.Nevertheless,low ion and electron transfer rate and poor cycling performance in the electrode practically restrict further promotion of their electrochemical performance.In order to offset the defect,a novel copper(Cu)foamsupported nickel molybdate nanosheet decorated carbon nanotube wrapped copper oxide nanowire array(NiMoO4 NSs-CNTs-CuO NWAs/Cu foam)flexible electrode is constructed.The as-prepared electrode demonstrates a unique core-shell holey nanostructure with a large active surface area,which can provide a large number of active sites for redox reactions.Besides,the CNTs networks supply improved conductivity,which can hasten electron transport.Through this simple and efficient design method,the spatial distribution of each component in the flexible electrode is more orderly,short and fast electron transport path with low intrinsic resistance.As a result,the NiMoO4 NSs-CNTs-CuO NWAs/Cu foam as an adhesiveless supercapacitor electrode material exhibits excellent ene rgy storage perfo rmance with high specific areal capacitance of 23.40 F cm^(-2)at a current density of 2 mA cm^(-2),which outperforms most of the flexible electrodes re ported recently.The assembled asymmetric supercapacitor demonstrates an energy density up to 96.40 mW h cm^(-3)and a power density up to 0.4 W cm^(-3)under a working voltage window of 1.7 V.In addition,outstanding flexibility of up to 100°bend and good cycling stability with the capacitance retention of 82.53%after 10,000 cycles can be obtained.
基金This work was supported by the National Natural Science Foundation of China(52101251)Natural Science Foun-dation of Hebei Province(B2021208030)+1 种基金College Students Inno-vation Training Program of Hebei Province(S2021113409001)STU Scientific Research Initiation Grant(NTF22018).Author contributions:J.S.,M.J.,and C.Z.led the project.The manuscript was primarily written by H.-M.Z.,and J.-J.W.,Y.M.,F.L.,and J.X.revised it.All authors contributed to the manu-script.Competing interests:The authors declare that they have no competing interests.
文摘Hydrogen energy is considered as an ideal energy with the advantages of green,sustainability,and high energy density,and water splitting is one of the efficient strategies for green hydrogen without carbon emission.As for cathodic hydrogen evolution reaction(HER),besides the Pt-based electrocatalysts with excellent electrocatalytic activities on HER,transition metal nitrides(TMNs)as cheap and facile-prepared electrocatalysts have shown remarkable electrocatalytic activities.Incorporation of N atom in metal interstitial lattice results in the unique structure of TMN with high electronic conductivity,strong chemical stability,and d-band contraction.Although the intrinsic electrocatalytic activities of TMNs are mostly lower than those of Pt,it also attracted much attention to the development of TMN with higher intrinsic activity by electronic structure modulation.Here,we review the recent improvement strategies for the intrinsic electrocatalytic activities of TMN catalysts on HER by electronic structure modulation,such as facet,alloying,doping,vacancy,heterostructure,and hybridization.Some important breakthroughs of TMNs have been made;however,the scale application of TMNs with high activity in commercial water electrolyzer is urgent to explore.The future development of TMNs is proposed to focus on developing facile synthesis methods,elucidating regulation mechanism and catalytic mechanism,and enhancing activity and stability.
