Aligned silica nanowire arrays and silica microflowers were fabricated using boron as the catalyst and under the flow N2 gas. The obtained product had no catalyst contamination. And silica nanowires had long lengths o...Aligned silica nanowire arrays and silica microflowers were fabricated using boron as the catalyst and under the flow N2 gas. The obtained product had no catalyst contamination. And silica nanowires had long lengths of a few hundreds. The growth of nanowire arrays and microflowers was explained using mechanism. Parallel-plate capacitors using silica nanowire mat as the dielectric were fabricated. The silica nanowire capacitor shows a specific capacitance of 0.24 n F/cm~2 at the frequency of 100 Hz. The capacitor is not monotone changing with the frequency. The measurement of mechanical properties shows that the tunneling current increases along with an increase in bending angle of the capacitor.展开更多
Near-field scanning optical microscopy is used to investigate the waveguiding properties of optical micro/nanofibres （MNFs） by means of detecting optical power carried by evanescent waves. Taper drawn silica and tel...Near-field scanning optical microscopy is used to investigate the waveguiding properties of optical micro/nanofibres （MNFs） by means of detecting optical power carried by evanescent waves. Taper drawn silica and tellurite MNFs, supported on low-index substrates, are used to guide a 532-nm-wavelength light beam for the test. Modification of the single-mode condition of the MNF in the presence of a substrate is observed. Spatial modulation of the longitudinal field intensity （with a 195-nm period） near the output end of a 760-nm-diameter silica MNF is well resolved. Energy exchange through evanescent coupling between two parallel MNFs is also investigated.展开更多
As one of the most delicate bioprocesses in nature,biosilicification is closely related to biosilica with various morphologies,and has provided abundant inspiration to materials synthesis.In the present study,to explo...As one of the most delicate bioprocesses in nature,biosilicification is closely related to biosilica with various morphologies,and has provided abundant inspiration to materials synthesis.In the present study,to explore the biosilica formation process and fabricate silica with an exquisite microstructure for lithiumion battery(LIB)electrodes,a bacterial phage(M13)is used as a biotemplate to synthesize silica with diverse morphologies:cylinders,hexagonal prisms,assemblies of smaller cylinders and nanowires.A facile ethanol bath method is conducted to coat the nanowires with nitrogen-containing carbon and carbon-coated SiO_(2) nanowires with mesochannels(C@msSiO_(2) NWs)are first used as anode materials for LIBs.Attributed to the uniform carbon coating and parallel mesochannel structure,the electronic conductivity and capacity to accommodate volume variations were significantly improved.In the electrochemical perfo rmance test,the composites calcined at 750℃(C@msSiO_(2) NWs-750)show an impressive capacity of 653 mA h g^(-1) at a current density of 500 mA g^(-1) and stability(1000 cycles).In view of the electrochemical test outcomes,the prepa ration of a sophisticated structure with an outstanding potential is easily achieved via a biomimetic strategy.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 61404036)the National Basic Research Program of China (No. 2012CB934104)+1 种基金the Fundamental Research Funds for the Central Universities (Nos. HIT. NSRIF.2015039, 01508536)State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (No. 2016 TS 06)
文摘Aligned silica nanowire arrays and silica microflowers were fabricated using boron as the catalyst and under the flow N2 gas. The obtained product had no catalyst contamination. And silica nanowires had long lengths of a few hundreds. The growth of nanowire arrays and microflowers was explained using mechanism. Parallel-plate capacitors using silica nanowire mat as the dielectric were fabricated. The silica nanowire capacitor shows a specific capacitance of 0.24 n F/cm~2 at the frequency of 100 Hz. The capacitor is not monotone changing with the frequency. The measurement of mechanical properties shows that the tunneling current increases along with an increase in bending angle of the capacitor.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60425517 and 60378036.
文摘Near-field scanning optical microscopy is used to investigate the waveguiding properties of optical micro/nanofibres （MNFs） by means of detecting optical power carried by evanescent waves. Taper drawn silica and tellurite MNFs, supported on low-index substrates, are used to guide a 532-nm-wavelength light beam for the test. Modification of the single-mode condition of the MNF in the presence of a substrate is observed. Spatial modulation of the longitudinal field intensity （with a 195-nm period） near the output end of a 760-nm-diameter silica MNF is well resolved. Energy exchange through evanescent coupling between two parallel MNFs is also investigated.
基金supported financially by the National Natural Science Foundation of China(Nos.51521001,51832003,51902236 and 31771032)。
文摘As one of the most delicate bioprocesses in nature,biosilicification is closely related to biosilica with various morphologies,and has provided abundant inspiration to materials synthesis.In the present study,to explore the biosilica formation process and fabricate silica with an exquisite microstructure for lithiumion battery(LIB)electrodes,a bacterial phage(M13)is used as a biotemplate to synthesize silica with diverse morphologies:cylinders,hexagonal prisms,assemblies of smaller cylinders and nanowires.A facile ethanol bath method is conducted to coat the nanowires with nitrogen-containing carbon and carbon-coated SiO_(2) nanowires with mesochannels(C@msSiO_(2) NWs)are first used as anode materials for LIBs.Attributed to the uniform carbon coating and parallel mesochannel structure,the electronic conductivity and capacity to accommodate volume variations were significantly improved.In the electrochemical perfo rmance test,the composites calcined at 750℃(C@msSiO_(2) NWs-750)show an impressive capacity of 653 mA h g^(-1) at a current density of 500 mA g^(-1) and stability(1000 cycles).In view of the electrochemical test outcomes,the prepa ration of a sophisticated structure with an outstanding potential is easily achieved via a biomimetic strategy.
