We report TiO2 branched nanostructure photoelectrodes for dye-sensitized solar cells (DSSCs). The TiO2 branch-type nanoparticle is synthesized by means of a seeding method with TiO2 nanowire as a seed. During the seeding process, the TiO2 nanostructure is evolved from a nanowire (NW) to nanobranch (NB) shape. It is also found that rutile TiO2-NB shows such a three-dimensional structure with branches grown along backbones of rutile TiO2-NW as confirmed by high-resolution transmission electron microscopy (HR-TEM) and X-ray diffraction (XRD) analysis. In photocurrent−voltage measurements, short-circuit current density, and cell efficiency of TiO2-NW and TiO2-NB increase from 6.25 to 12.18 mA/cm2 and increase from 2.6 to 4.3%, respectively, due to both increased specific surface area and roughness factor.
In this work, we demonstrated that Pt nanostructure electrodes could be obtained by the pulse electrodeposition method in polyvinylpyrrolidone (PVP). The nanocrystal particles were confirmed by scanning electron microscopy, transmission electron microscopy and x-ray diffraction methods. The average size of Pt nanoparticles deposited in additive PVP with low and high molecular weight is 3.4 and 2.9 nm, respectively, whereas that of Pt electrodeposited without PVP is 360 nm. This means that the size of Pt nanoparticles can be controlled by PVP, resulting in an increased electrochemical surface area. The resulting Pt nanostructure electrodes showed such an improved performance for both direct methanol fuel cells and dye-sensitized solar cells.
The H(2)-NO(3)(-) electrochemical cell using nitrate reduction on a non-precious cathode catalyst shows much improved efficiency despite ∼75% reduction of Pt metal loading as compared to typical PEMFCs using typical ORR on precious catalysts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.