Li1.02YxMn2-xO4(x = 0, 0. 005, 0.01, 0.02, 0.04, 0. 1) were prepared by solid state reaction method with raw materials Li2CO3, electrolytic MnO2 and Y2O3. Li1.02YxMn2-x O4 with different Y^3+ contents have good cry...Li1.02YxMn2-xO4(x = 0, 0. 005, 0.01, 0.02, 0.04, 0. 1) were prepared by solid state reaction method with raw materials Li2CO3, electrolytic MnO2 and Y2O3. Li1.02YxMn2-x O4 with different Y^3+ contents have good crystal structure, Y^3+ doping makes the lattice parameter and crystal volume small. Cyclic vohammogram testing result shows that a small quantity of Y^3+ doping has no influence on the Li^+ deinsertion-insertion process, but Y^3+ doping decreases the interacting force among Li^+ , and then availably avoids the energy level splitting. The electrochemical property testing indicates that the initial discharge ca- pacity at x =0.02 is 117.2 mAh·g^-1 and remains 96.9% with 113.6 mAhg^-1 after 20 cycles, which explains that Y^3+ doping effectively restricts Jahn-Teller effect and stabilizes the crystal structure. AC analysis shows that conductivity of the samples is clearly improved due to Y^3+ doping.展开更多
White body-color (Y, Gd)BxV1-xO4-x :Eu^3+ phosphors were prepared by coprecipitation reaction. Under VUV excitation at 147 nm, the red emission colorimetric purity of (Y, Gd) BxV1-xO4-x: Eu^3+ phosphor is much...White body-color (Y, Gd)BxV1-xO4-x :Eu^3+ phosphors were prepared by coprecipitation reaction. Under VUV excitation at 147 nm, the red emission colorimetric purity of (Y, Gd) BxV1-xO4-x: Eu^3+ phosphor is much better than that of commercial PDP (plasma display panels) phosphor (Y, Gd)BO3:Eu^3+ . But its relative emission intensity is only about 90% of the commercial phosphor.展开更多
Cost-effective catalysts for the oxidation of volatile organic compounds (VOCs) are critical to energy conversion applications and environmental protection. The main bottleneck of this process is the development of ...Cost-effective catalysts for the oxidation of volatile organic compounds (VOCs) are critical to energy conversion applications and environmental protection. The main bottleneck of this process is the development of an efficient, stable, and cost-effective catalyst that can oxidize HCHO at low temperature. Here, an advanced material consisting of manganese cobalt oxide nanosheet arrays uniformly covered on a carbon textile is successfully fabricated by a simple anodic electrodeposition method combined with post annealing treatment, and can be directly applied as a high-performance catalytic material for HCHO elimination. Benefiting from the increased surface oxygen species and improved redox properties, the as-prepared manganese cobalt oxide nanosheets showed substantially higher catalytic activity for HCHO oxidation. The catalyst completely converted HCHO to CO2 at temperatures as low as 100 ℃, and exhibited excellent catalytic stability. Such impressive results are rarely achieved by non-precious metal-based catalysts at such low temperatures.展开更多
文摘Li1.02YxMn2-xO4(x = 0, 0. 005, 0.01, 0.02, 0.04, 0. 1) were prepared by solid state reaction method with raw materials Li2CO3, electrolytic MnO2 and Y2O3. Li1.02YxMn2-x O4 with different Y^3+ contents have good crystal structure, Y^3+ doping makes the lattice parameter and crystal volume small. Cyclic vohammogram testing result shows that a small quantity of Y^3+ doping has no influence on the Li^+ deinsertion-insertion process, but Y^3+ doping decreases the interacting force among Li^+ , and then availably avoids the energy level splitting. The electrochemical property testing indicates that the initial discharge ca- pacity at x =0.02 is 117.2 mAh·g^-1 and remains 96.9% with 113.6 mAhg^-1 after 20 cycles, which explains that Y^3+ doping effectively restricts Jahn-Teller effect and stabilizes the crystal structure. AC analysis shows that conductivity of the samples is clearly improved due to Y^3+ doping.
文摘White body-color (Y, Gd)BxV1-xO4-x :Eu^3+ phosphors were prepared by coprecipitation reaction. Under VUV excitation at 147 nm, the red emission colorimetric purity of (Y, Gd) BxV1-xO4-x: Eu^3+ phosphor is much better than that of commercial PDP (plasma display panels) phosphor (Y, Gd)BO3:Eu^3+ . But its relative emission intensity is only about 90% of the commercial phosphor.
基金This work was preliminarily supported by the National Natural Science Foundation of China (Nos. 21425627 and 21276104) and Natural Science Foundation of Guangdong Province (Nos. 21425627).
文摘Cost-effective catalysts for the oxidation of volatile organic compounds (VOCs) are critical to energy conversion applications and environmental protection. The main bottleneck of this process is the development of an efficient, stable, and cost-effective catalyst that can oxidize HCHO at low temperature. Here, an advanced material consisting of manganese cobalt oxide nanosheet arrays uniformly covered on a carbon textile is successfully fabricated by a simple anodic electrodeposition method combined with post annealing treatment, and can be directly applied as a high-performance catalytic material for HCHO elimination. Benefiting from the increased surface oxygen species and improved redox properties, the as-prepared manganese cobalt oxide nanosheets showed substantially higher catalytic activity for HCHO oxidation. The catalyst completely converted HCHO to CO2 at temperatures as low as 100 ℃, and exhibited excellent catalytic stability. Such impressive results are rarely achieved by non-precious metal-based catalysts at such low temperatures.