This paper introduces a facile one-pot method for synthesizing a new structured material, named "ant-cave microball", by continuous ultrasonic spray pyrolysis. The ant-cave-structured microballs are prepared from a colloidal spray solution with polystyrene nanobeads and sucrose. Networking between the nanovoids formed by decomposition of the polystyrene nanobeads results in the formation of nanochannels. The electrochemical properties of these ant-cave-structured MoO3-C microballs, prepared as the first target material for lithium ion batteries, are investigated. The nanochannels are uniformly distributed inside the microballs with MoO3 and carbon components uniformly distributed within the microballs. Further, the microballs have initial discharge and charge capacities of 1212 and 841 mA h g(-1), respectively, at a current density of 2 A g(-1), and the initial discharge and charge capacities based on the weight of MoO3 (disregarding carbon component) are as high as 1814 and 1259 mA h g(-1). The microballs deliver a high discharge capacity of 733 mA h g(-1) even after 300 cycles. This is although microsized MoO3 powders with a filled structure have discharge capacities of 1256 and 345 mA h g(-1) for the first and 300th cycles, respectively.

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Sr 1-x , Zn x ) 1-y (Al 1.98 , B 0.02 )O 4 :Eu y 2+ green phosphor particles for ultraviolet light-emitting diodes (UV LEDs) were prepared by spray pyrolysis and their luminescent properties were investigated with changing the reducing temperature, the concentration of the activator, and the ratio of Sr to Zn. For the Sr(Al 1.98 , B 0.02 )O 4 :Eu 2+ phosphor, pure monoclinic SrAl 2 O 4 phase was formed when the post-treatment temperature was 1100-1200 °C. Over 1300 °C, however, the Sr 4 Al 14 O 25 phase appeared as a minor phase, which induced a blue shift in the emission peak. The highest intensity of Sr(Al 1.98 , B 0.02 )O 4 :Eu 2+ phosphor was achieved when the reducing temperature and the content of Eu 2+ were 1200 °C and 10 mol % of the strontium, respectively. It was found that the substitution of 10-50% Zn atoms instead of the strontium greatly enhanced the 520 nm green emission, especially for the excitation wavelength range from 380 to 420 nm. At the high Zn concentration (x > 0.7), a new blue (460 nm) emission was observed and stable even at ambient temperature. This blue emission disappeared when the Zn content became lower than 0.7. The excitation spectrum of (Sr 1-x , Zn x )(Al 1.98 , B 0.02 )O 4 :Eu 2+ phosphor (x e 0.7) well overlapped with the 460 nm blue emissions. Consequently, it was concluded that the new blue sites successfully played the role of sensitizer for the energy transfer, which is responsible for the enhancement of the luminescence intensity. Finally, the optimized phosphor (Sr 0.6 , Zn 0.4 ) 0.9 (Al 1.98 , B 0.02 )O 4 :Eu 2+ 0.1 showed 185% improved emission intensity compared with that of the Sr 0.9 (Al 1.98 , B 0.02 )O 4 :Eu 2+ 0.1 phosphor under ultraviolet (λ ex ) 393 nm) excitation.

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