Enhanced Charge Transport Properties of Dye-Sensitized Solar Cells Using TiN_xO_y Nanostructure Composite Photoanode

Abstract

In this Article, the improvement in the conversion efficiencies of dye-sensitized solar cells (DSSCs) was observed by integrating a small amount of thermally oxidized titanium nitride (TiN x O y ) particles into the hydrothermally growth TiO2 nanoparticles to form the composite photoanode. The oxidation of titanium nitride (TiN) to TiN x O y (N-doped TiO2) was achieved using a simple single-step annealing process at 450 °C for 1 h. The existence of the O–Ti–N linkage in TiN x O y was verified using X-ray photoemission spectroscopy (XPS). The DSSCs using the composite photoanode with 5 wt % of TiN x O y particles in TiO2 showed optimum conversion efficiency with a 25.6% improvement over the conventional DSSCs using only the mesoporous TiO2 layer as photoanode. Higher incident photon-current conversion efficiency (IPCE) values were also obtained for these composite photoanodes. This marked improvement was attributed to the combined synergetic effects of an extra absorption in the visible region and an enhanced efficiency in the electron transport. The extra absorption region at 400–500 nm for TiN x O y was observed using a UV–vis spectrophotometer. In addition, the reduction of charge transport resistance in the composite photoanode as verified using electrochemical impedance spectroscopy (EIS) has also contributed to faster electron transport through the interpenetrating oxide layer.

Nanocrystalline TiO2 micropillar arrays grafted on conductive glass supports: microscopic and spectroscopic studies

“…c o m / l o c a t e / t s f their direct electrical pathway, which causes a faster charge transport to the electrode, thus greatly reducing recombinations effects and then improving the performance of the optoelectronic devices (Scheme 1). To this purpose, vertically oriented arrays of nanotubes, rods, strips, cones and pillars made of anatase [22][23][24][25][26][27][28][29], rutile [9,[30][31][32] and by mixed anatase-rutile nanostructures [33,34], have been fabricated.…”

Enhanced photovoltaic performance of dye-sensitized solar cell using composite photoanode on 3D electrode

“…The procedure to prepare the TiN-TiO 2 composite paste has been described elsewhere 35 . In short, the TiN (97%, Hefei Kaier) nanoparticles with 5 wt% were added to the TiO 2 nanoparticles in ethanol and dispersed using stirring and ultrasonication (Sonics Vibra Cell VC505) to form a homogenized colloidal.…”

Effect of growth solution concentration on the performance of gallium doped ZnO nanostructures dye sensitized solar cells (DSSCs)

“…In order to improve the performance of the DSSCs, various treatments have been carried out, such as coated layer onto active materials [12] and doping of photovoltaic materials [13][14][15][16][17][18][19][20]. The materials are doped with metallic atoms, such as indium doped ZnO [13], cerium doped TiO 2 [14], stannum doped ZnO [15], boron doped ZnO [16], alluminium doped ZnO [17].…”

“…The materials are doped with metallic atoms, such as indium doped ZnO [13], cerium doped TiO 2 [14], stannum doped ZnO [15], boron doped ZnO [16], alluminium doped ZnO [17]. Doping can also be done by non-metallic materials, such as nitrogen doped TiO 2 [18][19][20], grapheme doped TiO 2 [21] and sulfur doped TiO 2 [22]. The doping with metallic and non-metallic materials can modify physical properties, such as morphology and optical properties.…”

“…The performance of DSSCs was influenced by the morphology of active materials of photoanode [13][14][15]. The band gap of active materials was lowered down, increasing the rate of free electron-hole pair and consequently improves the performance of the cells [18][19][20][21][22].…”