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Metal-organic frameworks and its derivates have attracted much attention for energy storage application. In this work, three-dimensional bimetallic metal-organic frameworks with novel hierarchical bundle-like micro/nanostructure were synthesized at room temperature for the first time. After initial carbonization and subsequent selenization, hierarchical porous Ni-Co-Se nanoparticles embedded in 3D carbon network with a high surface area that obviously inherited the original morphology of the bimetallic metal organic frameworks. The resulting materials demonstrated superior performance as the anode in lithium ion batteries (LIBs): they provide high reversible Li-storage capacity, excellent cyclability (2061 mA h/g after 300 cycles) and high rate performance (493 mA h/g at 8 A/g). The features of Ni-Co-Se@C electrode include the synergistic effect of two metal selenides species for Li-storage, well-designed hierarchical porous bundle-like structure, steady carbon network and as-formed size-reduced particles after initial cycle process. These features not only enhanced the electronic properties and alleviated the volume variation of metal selenides during the repeated cycles, but also produced more active sites for lithium storage and a shorter lithium diffusion pathway to expedite the fast charge transfer and preserve a stable SEI layer, resulting in outstanding lithium storage performance. In addition, the pseudocapacitive behaviour contributes much to the high energy storage of lithium ions. These results uncover a facile methodology for the design of well-organized MOFs and transition metal dichalcogenides with 3D hierarchical structures.

Metal-organic frameworks and its derivates have attracted much attention for energy storage application. In this work, three-dimensional bimetallic metal-organic frameworks with novel hierarchical bundle-like micro/nanostructure were synthesized at room temperature for the first time. After initial carbonization and subsequent selenization, hierarchical porous Ni-Co-Se nanoparticles embedded in 3D carbon network with a high surface area that obviously inherited the original morphology of the bimetallic metal organic frameworks. The resulting materials demonstrated superior performance as the anode in lithium ion batteries (LIBs): they provide high reversible Li-storage capacity, excellent cyclability (2061 mA h/g after 300 cycles) and high rate performance (493 mA h/g at 8 A/g). The features of Ni-Co-Se@C electrode include the synergistic effect of two metal selenides species for Li-storage, well-designed hierarchical porous bundle-like structure, steady carbon network and as-formed size-reduced particles after initial cycle process. These features not only enhanced the electronic properties and alleviated the volume variation of metal selenides during the repeated cycles, but also produced more active sites for lithium storage and a shorter lithium diffusion pathway to expedite the fast charge transfer and preserve a stable SEI layer, resulting in outstanding lithium storage performance. In addition, the pseudocapacitive behaviour contributes much to the high energy storage of lithium ions. These results uncover a facile methodology for the design of well-organized MOFs and transition metal dichalcogenides with 3D hierarchical structures.

Metal-organic frameworks and its derivates have attracted much attention for energy storage application. In this work, three-dimensional bimetallic metal-organic frameworks with novel hierarchical bundle-like micro/nanostructure were synthesized at room temperature for the first time. After initial carbonization and subsequent selenization, hierarchical porous Ni-Co-Se nanoparticles embedded in 3D carbon network with a high surface area that obviously inherited the original morphology of the bimetallic metal organic frameworks. The resulting materials demonstrated superior performance as the anode in lithium ion batteries (LIBs): they provide high reversible Li-storage capacity, excellent cyclability (2061 mA h/g after 300 cycles) and high rate performance (493 mA h/g at 8 A/g). The features of Ni-Co-Se@C electrode include the synergistic effect of two metal selenides species for Li-storage, well-designed hierarchical porous bundle-like structure, steady carbon network and as-formed size-reduced particles after initial cycle process. These features not only enhanced the electronic properties and alleviated the volume variation of metal selenides during the repeated cycles, but also produced more active sites for lithium storage and a shorter lithium diffusion pathway to expedite the fast charge transfer and preserve a stable SEI layer, resulting in outstanding lithium storage performance. In addition, the pseudocapacitive behaviour contributes much to the high energy storage of lithium ions. These results uncover a facile methodology for the design of well-organized MOFs and transition metal dichalcogenides with 3D hierarchical structures.

Metal-organic frameworks and its derivates have attracted much attention for energy storage application. In this work, three-dimensional bimetallic metal-organic frameworks with novel hierarchical bundle-like micro/nanostructure were synthesized at room temperature for the first time. After initial carbonization and subsequent selenization, hierarchical porous Ni-Co-Se nanoparticles embedded in 3D carbon network with a high surface area that obviously inherited the original morphology of the bimetallic metal organic frameworks. The resulting materials demonstrated superior performance as the anode in lithium ion batteries (LIBs): they provide high reversible Li-storage capacity, excellent cyclability (2061 mA h/g after 300 cycles) and high rate performance (493 mA h/g at 8 A/g). The features of Ni-Co-Se@C electrode include the synergistic effect of two metal selenides species for Li-storage, well-designed hierarchical porous bundle-like structure, steady carbon network and as-formed size-reduced particles after initial cycle process. These features not only enhanced the electronic properties and alleviated the volume variation of metal selenides during the repeated cycles, but also produced more active sites for lithium storage and a shorter lithium diffusion pathway to expedite the fast charge transfer and preserve a stable SEI layer, resulting in outstanding lithium storage performance. In addition, the pseudocapacitive behaviour contributes much to the high energy storage of lithium ions. These results uncover a facile methodology for the design of well-organized MOFs and transition metal dichalcogenides with 3D hierarchical structures.

A big gap exists for the understanding of the influence of temperature on erosion behavior at elevated temperature between experimental observations (up to 1100 °C) and high temperature industrial application (up to 1600 °C). This work the first time investigated the effect of higher temperature on the erosion resistance and mechanism of alumina ceramics. The solid particle erosion behavior of high purity alumina ceramics has been studied at elevated temperatures up to 1400 °C and different impingement angles (30°, 45°, 60°, 75°, and 90°), using corundum and SiC particles as erodent. Erosion rate of alumina ceramics slowly increases from 0.32 mm 3 g-1 to 0.44 mm3 g-1 below 800 °C, and then significantly increases up to 1.30 mm3 g -1 at 1400 °C. With increasing the impingement angle, the erosion rate increases slightly and reaches maximum value at 90° from room temperature to 800 °C. However, the maximum value of erosion rate occurs at 75° and 60° for 1200 °C and 1400 °C, respectively. The brittle erosion mechanisms still dominate the material removal at elevated temperature. The material removal is mainly resulted from transgranular cleavage and grain removal.

The results of thermodynamic analysis showed that phase compositions of the composites depended on the synthesis temperature for the carbothermal reduction nitriding (CRN) reaction, which was optimised at 1 550 degrees C for 4 h after which Si3Al3O3N5 and SiC phases were proved to co-exist in the same particle. This transformation provides a feasible route for utilising low-quality kyanite tailings from Gansu, China, containing quartz, phlogopite, albite and muscovite, along with carbon coke from Shanxi, as raw materials for high-temperature applications., The results of thermodynamic analysis showed that phase compositions of the composites depended on the synthesis temperature for the carbothermal reduction nitriding (CRN) reaction, which was optimised at 1 550 degrees C for 4 h after which Si3Al3O3N5 and SiC phases were proved to co-exist in the same particle. This transformation provides a feasible route for utilising low-quality kyanite tailings from Gansu, China, containing quartz, phlogopite, albite and muscovite, along with carbon coke from Shanxi, as raw materials for high-temperature applications.