Preparation of Nanocrystalline TiO₂ Electrodes for Flexible Dye-Sensitized Solar Cells: Influence of Mechanical Compression

Abstract

Registro de acceso restringido Este recurso no está disponible en acceso abierto por política de la editorial. No obstante, se puede acceder al texto completo desde la Universitat Jaume I o si el usuario cuenta con suscripción. Registre d'accés restringit Aquest recurs no està disponible en accés obert per política de l'editorial. No obstant això, es pot accedir al text complet des de la Universitat Jaume I o si l'usuari compta amb subscripció. Restricted access item This item isn't open access because of publisher's policy. The full--text version is only available from Jaume I University or if the user has a running suscription to the publisher's contents.

Insights into mechanical compression and the enhancement in performance by Mg(OH)2 coating in flexible dye sensitized solar cells

“…Similar features appear in the R HF reported in our previous study evaluating the influence on the mechanical compression where 90 we suggested that a corrosion or degradation process could be responsible for the behavior observed. 9 However, the further analysis performed here points out to the existence of a shunt resistance as explained above.…”

“…Our previous impedance analysis in the dark on flexible DSCs revealed that compression of TiO 2 electrodes causes significant differences in the high frequency region (left part) of the 15 impedance spectra. 9 This region usually only indicates the oxidation of the redox mediator at the platinized counter electrode. This oxidation process is described by a semicircle consisting on the parallel combination of R Pt and C Pt .…”

Reduction of crack formation in TiO 2 mesoporous films prepared from binder-free nanoparticle pastes via incorporation of electrospun SiO 2 or TiO 2 nanofibers for dye-sensitized solar cells

“…The observed crack formation (and film deformation behavior) is a typical problem in the thin film prepared from binder-free paste; various reasons have been suggested to explain the formation of cracks, including the particle agglomeration during the drying process [21], the residual stress between packed particles and settled particles [22], the non-uniform distribution of temperature and humidity inside the film [23], and the deformation of ordered nanoparticle array by the van der Waals force and capillary force [24]. In this work, the binder-free TiO 2 nanoparticle paste contained ~86 wt.% of solvent (i.e., water).…”

“…During the evaporation, capillary forces would be developed near the surface of wet TiO 2 film due to the water-TiO 2 meniscuses formed among TiO 2 nanoparticles. Such capillary forces would increase along with the continuing evaporation of water, leading to the development of internal stress accompanied by the consolidation and shrinkage of the TiO 2 film; cracks would then be generated when the internal stress exceeded the tensile strength of TiO 2 film [24,25]. A thin mat of continuous SiO 2 nanofibers covered on the surface of TiO 2 film could reduce the capillary forces, and thus the internal stress development would be mitigated during the water evaporation.…”

Hybrid Dye‐Titania Nanoparticles for Superior Low‐Temperature Dye‐Sensitized Solar Cells

“…to reduce the sintering temperatures while improving the nanoparticle interconnection -multiple strategies have been proposed in literature. The most promising approaches include, i) binderfree pastes, [33][34][35] ii) the compression treatment, [36][37][38][39][40][41] iii) spray and/or electrophoretic depositions, [42][43][44] iv) lift-off transfer technique, 45 v) the use of a polymer composite matrix, 46,47 and vi) interconnected nanoparticle-embedded microbead-type TiO2. 48,49 The resulting efficiencies have been moderate, usually ranging between 4-7%, 11,[33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] while the highest efficiency of 8.1% was reported by Yamaguchi et al in 2010.…”