TiO₂‐Coated Multilayered SnO₂ Hollow Microspheres for Dye‐Sensitized Solar Cells

Abstract

Dye-sensitized solar cells (DSSCs) have attracted extensive interest in past decade as a promising candidate for the future generation of cost-effective photovoltaic solar cells. [1][2][3][4][5] Since the first demonstration of 10.4% photoconversion efficiency on TiO 2 -based DSSC, [6] intensive work in DSSC research has been devoted to the synthetic chemistry and structural and photovoltaic characterization of mesoporous nanocrystalline TiO 2 materials. [7][8][9] In contrast, other metal oxide semiconductors, such as tin and zinc oxides, have received less attention, though they have required band-gap widths and photoelectrochemical properties as TiO 2 . In fact, SnO 2 has at least two advantageous features compared to TiO 2 for DSSC applications: its higher electron mobility ($100-200 cm 2 V À1 S À1[10]) than TiO 2 ($0.1-1.0 cm 2 V À1 S À1[11]), suggesting a faster diffusion transport of photoinduced electrons in SnO 2 than in TiO 2 ; and its larger band gap (3.6 eV) than anatase TiO 2 (3.2 eV), which would create fewer oxidative holes in the valence band, so as to facilitate the long-term stability of DSSCs. However, SnO 2 -based DSSCs were developed with less success, and the conversion efficiencies of SnO 2 photoelectrodes reported so far are much less than those of TiO 2 . [12,13]

Contribution of multiple reflections to light utilization efficiency of submicron hollow TiO2 photocatalyst

“…Recent works have also revealed that multi-shelled hollow spheres exhibit a greatly enhanced photocatalytic activity or photoelectric conversion efficiency due to multiple-reflections of light [37,38]. To verify the multiple reflections effect in the multi-shelled hollow TiO2, double shelled TiO2 was synthesized by utilizing T450 (Fig.…”

Synthesis, characterization and photocatalytic applications of Zn-doped TiO2 nanoparticles by sol–gel method

“…Over the past decades, semiconducting photocatalytic materials like ZnO, TiO 2 are widely applied for degradation and complete mineralization of toxic organic compounds in water, soil, and air (Zeng et al 2008;Qian et al 2009). Titania (TiO 2 ) based catalyst is widely applied for decomposition of toxic organic chemicals both in the aqueous and gas phase due to its unique properties like nontoxicity, chemical stability, high photocatalytic activity and low cost.…”

Porous Titania Nanosheet/Nanoparticle Hybrids as Photoanodes for Dye-Sensitized Solar Cells

“…An optical scattering layer on top has been proposed as it could enhance the light harvest by localizing the incident light within the photoanode. So far, an array of light scattering materials has been investigated, including TiO2 mesoporous microspheres, 7,8 hollow spheres [9][10][11] and mirror-like nanoparticles. 12,13 Another major drawback of the conventional TiO2 nanoparticle photoanodes is the low transport efficiency of electrons, which imposes an upper limit on the film thickness.…”