Recent efforts have focused on the fabrication and application of three- dimensional (3-D) nanoarchitecture electrodes, which can exhibit excellent electrochemical performance. Herein, a novel strategy towards the d...Recent efforts have focused on the fabrication and application of three- dimensional (3-D) nanoarchitecture electrodes, which can exhibit excellent electrochemical performance. Herein, a novel strategy towards the design and synthesis of size- and thickness-tunable two-dimensional (2-D) MnO2 nanosheets on highly conductive one-dimensional (l-D) backbone arrays has been developed via a facile, one-step enhanced chemical bath deposition (ECBD) method at a low temperature (-50 ℃). Inclusion of an oxidizing agent, BrO3-, in the solution was crucial in controlling the heterogeneous nucleation and growth of the nanosheets, and in inducing the formation of the tailored and uniformly arranged nanosheet arrays. We fabricated supercapacitor devices based on 3-D MnO2 nanosheets with conductive Sb-doped SnO2 nanobelts as the backbone. They achieved a specific capacitance of 162 F·g-1 at an extremely high current density of 20 A·g% and good cycling stability that shows a capacitance retention of -92% of its initial value, along with a coulombic efficiency of almost 100% after 5,000 cycles in an aqueous solution of I M Na2SO4. The results were attributed to the unique hierarchical structures, which provided a short diffusion path of electrolyte ions by means of the 2-D sheets and direct electrical connections to the current collector by 1-D arrays as well as the prevention of aggregation by virtue of the well-aligned 3-D structure.展开更多
We report the facile, one-pot synthesis of 3-D urchin-like W18O49 nanostructures (U-WO) via a simple solvothermal approach. An excellent supercapacitive performance was achieved by the U-WO because of its large Brun...We report the facile, one-pot synthesis of 3-D urchin-like W18O49 nanostructures (U-WO) via a simple solvothermal approach. An excellent supercapacitive performance was achieved by the U-WO because of its large Brunauer-Emmett- Teller (BET) specific surface area (ca. 123 m2.g-1) and unique morphological and structural features. The U-WO electrodes not only exhibit a high rate-capability with a specific capacitance (Csp) of -235 F·g-1 at a current density of 20 A.g-1, but also superior long-life performance for 1,000 cycles, and even up to 7,000 cycles, showing -176 F·g-1 at a high current density of 40 A.g-1.展开更多
文摘Recent efforts have focused on the fabrication and application of three- dimensional (3-D) nanoarchitecture electrodes, which can exhibit excellent electrochemical performance. Herein, a novel strategy towards the design and synthesis of size- and thickness-tunable two-dimensional (2-D) MnO2 nanosheets on highly conductive one-dimensional (l-D) backbone arrays has been developed via a facile, one-step enhanced chemical bath deposition (ECBD) method at a low temperature (-50 ℃). Inclusion of an oxidizing agent, BrO3-, in the solution was crucial in controlling the heterogeneous nucleation and growth of the nanosheets, and in inducing the formation of the tailored and uniformly arranged nanosheet arrays. We fabricated supercapacitor devices based on 3-D MnO2 nanosheets with conductive Sb-doped SnO2 nanobelts as the backbone. They achieved a specific capacitance of 162 F·g-1 at an extremely high current density of 20 A·g% and good cycling stability that shows a capacitance retention of -92% of its initial value, along with a coulombic efficiency of almost 100% after 5,000 cycles in an aqueous solution of I M Na2SO4. The results were attributed to the unique hierarchical structures, which provided a short diffusion path of electrolyte ions by means of the 2-D sheets and direct electrical connections to the current collector by 1-D arrays as well as the prevention of aggregation by virtue of the well-aligned 3-D structure.
文摘We report the facile, one-pot synthesis of 3-D urchin-like W18O49 nanostructures (U-WO) via a simple solvothermal approach. An excellent supercapacitive performance was achieved by the U-WO because of its large Brunauer-Emmett- Teller (BET) specific surface area (ca. 123 m2.g-1) and unique morphological and structural features. The U-WO electrodes not only exhibit a high rate-capability with a specific capacitance (Csp) of -235 F·g-1 at a current density of 20 A.g-1, but also superior long-life performance for 1,000 cycles, and even up to 7,000 cycles, showing -176 F·g-1 at a high current density of 40 A.g-1.