Abstract: The present invention relates to a porous copper sulfide nano/micro hollow sphere and a method for preparing the same. The porous copper sulfide nano/micro hollow sphere of the present invention has plural through holes and a hollow structure so as to increase the reactive area thereof. In particular, the porous copper sulfide nano/micro hollow sphere can be applied in a solar cell to enhance a photoelectric effect.

Abstract: The present invention relates to a circularly polarized antenna and, more particularly, to a compact circularly polarized antenna for transmitting and receiving a circularly polarized signal. The circularly polarized antenna comprises a substrate having an upper surface and a lower surface; a signal distributor; an antenna for transmitting and receiving the circularly polarized signal; and a plurality of support units. The upper surface of the substrate comprises a plurality of slots. One end of each slot overlaps with the respective ends of the other slots at a central region. The lower surface of the substrate comprises a coupling unit being electrically connected with the signal distributor, and the center of the coupling unit corresponds to the central region.