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Abstract In this work, we describe a new species of genus Bufo, Bufo exiguus sp. nov. from Mt. Nankun, Guangdong Province, China. This new species can be distinguished from all congeners by significant divergences in the mitochondrial 16S rRNA and CO1 genes and by a combination of morphological characters: small body size, tympanum absent, parotoid glands small and olive-shaped, tarsal fold absent, dorsal body with a fine vertebral line and white nuptial spinules present on dorsal and inner surfaces of fingers I and II in males. At present, Bufo exiguus sp. nov. is only known from the slow-flowing montane streams from its type locality and its conservation status should be carefully addressed.

This article presents significant experimental data about the dye-sensitized nano solar cells (DSSCs) using the new developed photo-electrode with reversal constituent structure in our CCT laboratory. The conventional constituent structure of a photo-electrode arranged in sequence from the incident light is the transparent conductive glass, the nano TiO2 semi-conductive porous film, and the dye. In process, the photons energy of the incident light is mainly absorbed by the dye for DSSCs. This causes excited electrons in the dye to jump into conductive band of the TiO2 and further to transfer into the outer circuit through the conductive glass. That is, a correct constituent structure of the photo-electrode arranged in sequence from the incident light in terms of the working principle should be the dye, the nano TiO2 film, and the conductive substrate. The conventional constituent structure of the photo-electrode causes the incident light to be hindered by the TiO2 layer. To reduce the light hindrance for the dye, this work used copper mesh as the conductive substrate and the nano TiO2 was coated on it. In this way, the copper mesh connects the nano TiO2 layer with the outer circuit and the holes of the copper mesh also allow the dye to contact with the electrolyte. The new developed constituent structure of the photo-electrode arranged in sequence from the incident light is the dye, the nano TiO2 film, and the copper mesh. This new constituent structure, which increases amounts of the absorption light in the dye and further improved the short-circuit current as well as the photoelectric conversion efficiency of DSSCs is reverse to the conventional constituent structure.

In general, the dye-sensitized nano-solar cell (DSSC) uses nano-metallic oxide, e.g. nano- TiO 2 , as N-type semiconductor integrated with dye to build its photoelectrode. The applied dye in connection with the metallic oxide in photoelectrode helps the DSSC to expand its absorption spectra into visible spectrum. This work added nano-carbon black ( ϕ = 22 nm ) in photoelectrode and used the nano-carbon black as bridge between the nano- TiO 2 and the alizarin yellow. Experiments used spray technique to build the nano- TiO 2 layer with ca. 67% light transmittance on the ITO glass as the semiconduction photoelectrode. The sintering process was 400 ° C for 60 min. The carbon black and the alizarin yellow had been first mixed as liquid solution before the semiconduction photoelectrode was immersed in it. The three kinds of nano-particles are connected each other and built in a triangular structure according to the compared results of three possible structural integrations in this work. The added carbon black played the role of catalyst to help electrons excitation of the alizarin yellow and enhanced the conductive band of the nano- TiO 2 . The results show that the photoelectric conversion efficiency of the improved DSSCs has ca. double increasement and its open-circuit voltage increases from ca. 0.5 V to ca. 0.6 V. The short-circuit current variation depends on added amount of the carbon black and receives the result, the larger the added amount, the bigger the short-circuit current.