Nitrogen-doped carbon nanotubes (N-CNTs)/polyaniline (PANI) composites are developed as an electrode material for biosensors. The morphology, composition, and optical properties of the resulting products were characte...Nitrogen-doped carbon nanotubes (N-CNTs)/polyaniline (PANI) composites are developed as an electrode material for biosensors. The morphology, composition, and optical properties of the resulting products were characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and ultraviolet-visible absorption spectra (UV-vis). Furthermore, N-CNTs/PANI composite was immobilized on the surface of a glassy carbon electrode (GCE) and applied to construct a sensor. The obtained N-CNTs/PANI-modified GCE showed one pair of redox peaks and high catalytic activity for the oxidation of dopamine (DA) in a neutral environment. Differential pulse voltam-mograms results illustrate that the fabricated DA biosensor has high anti-interference ability towards ascorbic acid (AA). In addition, the fabricated biosensor showed superior performances with two wide linear ranges from 1 to 80 μM and from 1.5 to 3.5 mM and a low detection limit of 0.01 μM.展开更多
It is a big challenge to prepare non-rare metal and high-activity electrocatalysts for oxygen reduction reaction(ORR).In this paper,a cobalt/carbon nanotubes/chitosan composite gel was synthesized and then annealed un...It is a big challenge to prepare non-rare metal and high-activity electrocatalysts for oxygen reduction reaction(ORR).In this paper,a cobalt/carbon nanotubes/chitosan composite gel was synthesized and then annealed under nitrogen atmosphere to yield the cobalt and nitrogen co-modified carbon nanotubes(Co-N-CNTs)nanocomposite electrocatalysts.In this strategy,the cobalt component considerably enhanced the ORR activity and improved the degree of graphitic structure to increase the electronic conductivity.The chitosan served as sustainable source for nitrogen doping.The Co-N-CNTs exhibit excellent oxygen reduction reaction(ORR)electrocatalytic activity due to the synergetic effect of Co species and N-doping.The Co-N-CNTs also deliver excellent methanol tolerance and superior long-term durability to that of commercial Pt/C,making it a promising ORR electrocatalyst.展开更多
Silicon is attracting considerable attention as an active anode material for advanced lithium-ion batteries due to its ultrahigh theoretical capacity. However, the reversible utilization of silicon-based anode materia...Silicon is attracting considerable attention as an active anode material for advanced lithium-ion batteries due to its ultrahigh theoretical capacity. However, the reversible utilization of silicon-based anode materials is still hindered by the rapid capacity decay, as a consequence of the huge volume change of silicon during cycling. Herein, we use a Co-zeolitic imidazole framework(ZIF-67) to prepare silicon-wrapped nitrogen-doped carbon nanotubes(Si@N-doped CNTs) by controllable thermal pyrolysis. The asprepared nanocomposites can effectively prevent pulverization and accommodate volume fluctuations of silicon during cycling. It can deliver a highly reversible capacity of 1100 m Ah g-1 even after 750 cycles at a current density of 1000 m A g-1. As confirmed by an in situ transmission electron microscopy experiment, the remarkable electrochemical performance of Si@N-doped CNTs is attributed to the high electronic conductivity and flexibility of cross-linked N-doped CNTs network as a cushion to mitigate the mechanical stress and volume expansion. Furthermore, a full cell consisting of Si@N-doped CNTs anode and Li Fe PO4 cathode delivers a high reversible capacity of 1264 m Ah g-1 and exhibits good cycling stability(>85% capacity retention) over 140 cycles at 1/4 C(1 C = 4000 m A g-1) rate.展开更多
基金supported by the National Natural Science Foundation of China (20905038, 20903057, 20974046, 50803027, 20874048 & 20804020)the National Basic Research Program of China (2009CB930600)+1 种基金the Natural Science Foundation of Jiangsu Province (08KJB150011 & 09KJB150007)the Fok Ying-Tong Education Foundation under Grant 111051
文摘Nitrogen-doped carbon nanotubes (N-CNTs)/polyaniline (PANI) composites are developed as an electrode material for biosensors. The morphology, composition, and optical properties of the resulting products were characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and ultraviolet-visible absorption spectra (UV-vis). Furthermore, N-CNTs/PANI composite was immobilized on the surface of a glassy carbon electrode (GCE) and applied to construct a sensor. The obtained N-CNTs/PANI-modified GCE showed one pair of redox peaks and high catalytic activity for the oxidation of dopamine (DA) in a neutral environment. Differential pulse voltam-mograms results illustrate that the fabricated DA biosensor has high anti-interference ability towards ascorbic acid (AA). In addition, the fabricated biosensor showed superior performances with two wide linear ranges from 1 to 80 μM and from 1.5 to 3.5 mM and a low detection limit of 0.01 μM.
基金financially supported by the National Natural Science Foundation of China(No.21671096 and 21603094)the Natural Science Foundation of Guangdong Province(No.2016A030310376)+2 种基金the Guangdong Special Support for the Science and Technology Leading Young Scientist(No.2016TQ03C919)the Guangdong Innovative and Entrepreneurial Research Team Program(No.2016ZT06G587)the Basic Research Project of the Science and Technology Innovation Commission of Shenzhen(No.JCYJ20170412153139454 and JCYJ20170817110251498)。
文摘It is a big challenge to prepare non-rare metal and high-activity electrocatalysts for oxygen reduction reaction(ORR).In this paper,a cobalt/carbon nanotubes/chitosan composite gel was synthesized and then annealed under nitrogen atmosphere to yield the cobalt and nitrogen co-modified carbon nanotubes(Co-N-CNTs)nanocomposite electrocatalysts.In this strategy,the cobalt component considerably enhanced the ORR activity and improved the degree of graphitic structure to increase the electronic conductivity.The chitosan served as sustainable source for nitrogen doping.The Co-N-CNTs exhibit excellent oxygen reduction reaction(ORR)electrocatalytic activity due to the synergetic effect of Co species and N-doping.The Co-N-CNTs also deliver excellent methanol tolerance and superior long-term durability to that of commercial Pt/C,making it a promising ORR electrocatalyst.
基金supported by the National Key Research and Development Program of China (2018YFA0209600)the National Natural Science Foundation of China (21872058)+1 种基金the Key Project of Science and Technology in Guangdong Province (2017A010106006)the Guangdong Special Support Program (2017TQ04N052)。
文摘Silicon is attracting considerable attention as an active anode material for advanced lithium-ion batteries due to its ultrahigh theoretical capacity. However, the reversible utilization of silicon-based anode materials is still hindered by the rapid capacity decay, as a consequence of the huge volume change of silicon during cycling. Herein, we use a Co-zeolitic imidazole framework(ZIF-67) to prepare silicon-wrapped nitrogen-doped carbon nanotubes(Si@N-doped CNTs) by controllable thermal pyrolysis. The asprepared nanocomposites can effectively prevent pulverization and accommodate volume fluctuations of silicon during cycling. It can deliver a highly reversible capacity of 1100 m Ah g-1 even after 750 cycles at a current density of 1000 m A g-1. As confirmed by an in situ transmission electron microscopy experiment, the remarkable electrochemical performance of Si@N-doped CNTs is attributed to the high electronic conductivity and flexibility of cross-linked N-doped CNTs network as a cushion to mitigate the mechanical stress and volume expansion. Furthermore, a full cell consisting of Si@N-doped CNTs anode and Li Fe PO4 cathode delivers a high reversible capacity of 1264 m Ah g-1 and exhibits good cycling stability(>85% capacity retention) over 140 cycles at 1/4 C(1 C = 4000 m A g-1) rate.
