TheCo3O4 nanosheet-built hollow dodecahedrons(Co3 O4 NSHDs) were fabricated via a controllable twostep self-templated method. The ZIF-67 dodecahedrons were prepared as first self-template to synthesize the Co-LDH holl...TheCo3O4 nanosheet-built hollow dodecahedrons(Co3 O4 NSHDs) were fabricated via a controllable twostep self-templated method. The ZIF-67 dodecahedrons were prepared as first self-template to synthesize the Co-LDH hollow dodecahedrons, which were further used as self-template to fabricateCo3O4 NSHDs by a controlled calcination.The proposed two-step self-templated method not only brings hollow structures without auxiliary template, ultrathin nanosheet, ultrafine grains, and large surface areas, but also allows the easy and uniform surface modification, as demonstrated of PdO modification. TheCo3O4 NSHDs with above features could show multifunctional applications, such as sensing and catalysis. Experiments suggest that theCo3O4 NSHDs show good gas sensing performances to trimethylamine at a low operating temperature(100 oC). They can be further enhanced by PdO surface modification, which have a low detection limit(250 ppb) and a short response time(4.5 s).In addition, theCo3O4 NSHDs exhibited excellent oxygen evolution reaction performances with a low overpotential of359 mV, low Tafel slope of 80.7 mV dec-1 and low electrochemical impedance, which was superior to those for theCo3O4 NCs obtained by directly calcinating the ZIF-67 templates,Ni foam and most common metal oxides catalysts.展开更多
Various metallic structures of complex shape resembling living plant organisms （biomimetics） are produced as a result of self-assembly of nanowires growing on porous membranes in the course of pulse current electrod...Various metallic structures of complex shape resembling living plant organisms （biomimetics） are produced as a result of self-assembly of nanowires growing on porous membranes in the course of pulse current electrodeposition. These structures occur if the electroplating is continued after the nanowires appear on the membrane surface. By varying the membrane ge- ometry, pulse current electroplating parameters, and alternating electrodeposition from two baths composed of a variety of electrolytes, diverse models were fabricated, including a hollow container with a wall thickness of 10 nm 20 nm. This biomimetic method suggests an analogy between the shape-forming processes of plants and their metallic models. Nanostruc- tured mesostructures of various metals （Ag, Pd, Ni）, alloys （PdNi, Pbln） and hybrid structures .（PdNi/Pb, PdNi/Pbln） were obtained. They can be of interest for fundamental research （self-assembly, morphogenesis） as well as for applications in nanotechnology （catalysis, nanoplasmonics, medicine, superhydrophobic surfaces）.展开更多
基金financial support from the National Key R&D Program of China(2016YFC0201103)the Natural Science Foundation of China(51471161 and 11674320)Youth Innovation Promotion Association CAS and Key Research Projects of the Frontier Science CAS(QYZDB-SSW-JSC017)
文摘TheCo3O4 nanosheet-built hollow dodecahedrons(Co3 O4 NSHDs) were fabricated via a controllable twostep self-templated method. The ZIF-67 dodecahedrons were prepared as first self-template to synthesize the Co-LDH hollow dodecahedrons, which were further used as self-template to fabricateCo3O4 NSHDs by a controlled calcination.The proposed two-step self-templated method not only brings hollow structures without auxiliary template, ultrathin nanosheet, ultrafine grains, and large surface areas, but also allows the easy and uniform surface modification, as demonstrated of PdO modification. TheCo3O4 NSHDs with above features could show multifunctional applications, such as sensing and catalysis. Experiments suggest that theCo3O4 NSHDs show good gas sensing performances to trimethylamine at a low operating temperature(100 oC). They can be further enhanced by PdO surface modification, which have a low detection limit(250 ppb) and a short response time(4.5 s).In addition, theCo3O4 NSHDs exhibited excellent oxygen evolution reaction performances with a low overpotential of359 mV, low Tafel slope of 80.7 mV dec-1 and low electrochemical impedance, which was superior to those for theCo3O4 NCs obtained by directly calcinating the ZIF-67 templates,Ni foam and most common metal oxides catalysts.
文摘Various metallic structures of complex shape resembling living plant organisms （biomimetics） are produced as a result of self-assembly of nanowires growing on porous membranes in the course of pulse current electrodeposition. These structures occur if the electroplating is continued after the nanowires appear on the membrane surface. By varying the membrane ge- ometry, pulse current electroplating parameters, and alternating electrodeposition from two baths composed of a variety of electrolytes, diverse models were fabricated, including a hollow container with a wall thickness of 10 nm 20 nm. This biomimetic method suggests an analogy between the shape-forming processes of plants and their metallic models. Nanostruc- tured mesostructures of various metals （Ag, Pd, Ni）, alloys （PdNi, Pbln） and hybrid structures .（PdNi/Pb, PdNi/Pbln） were obtained. They can be of interest for fundamental research （self-assembly, morphogenesis） as well as for applications in nanotechnology （catalysis, nanoplasmonics, medicine, superhydrophobic surfaces）.
