Photovoltaic activity of Ti/MCM‐41

Abstract

Ti/MCM-41 is a well-known heterogeneous catalyst for alkene epoxidation with organic peroxides. This titanosilicate contains isolated titanium atoms forming part of a framework of mesoporous silica whose structure is formed by parallel hexagonal channels 3.2 nm in diameter. The surface area and porosity of Ti/MCM-41 are about 880 m(2) g(-1) and 0.70 cm(3) g(-1), respectively. These values are among the highest for any material. Herein, we show that Ti/MCM-41 exhibits photovoltaic activity. Dye-sensitized solar cells using mesoporous Ti/MCM-41 (2.8-5.7 % Ti content) as active layer, black dye N3 as photosensitizer and I(3) (-)/I(-) in methoxyacetonitrile as electrolyte exhibit a V(OC), J(SC) and FF of 0.44 V, 0.045 mA cm(-2) and 0.33, respectively. These values compare well against 0.75 V, 4.1 mA cm(-2) and 0.64, respectively, measured for analogous solar cells using conventional P-25 TiO(2). However, the specific current density (J(SC)/Ti atom) for the Ti/MCM-41 is very similar to that of P25 TiO(2).

Luminescent silver–lithium-zeolite phosphors for near-ultraviolet LED applications

“…This layer was prepared by mixing 60 mg of zeolite phosphor with a solution of 0.33 ml α-terpineol (90%, Sigma Aldrich) and 34 mg ethylcellulose (48% ethoxyl, Sigma Aldrich) in 1 ml of acetone (Spectrograde, Sigma Aldrich), and coated on top of the substrate by doctor blade technique in two parallel adhesive Scotch tapes (1 x 1 cm). 34,35 Subsequently, the substrate was gradually heated up to 450 °C and kept at that temperature overnight in order to remove the organic material and dehydrate the Ag1 Li-LTA phosphor layer. Finally, the dehydrated phosphor layer was enclosed by applying the second silica substrate and sealing the layer at the sides by using parafilm.…”

Photochemistry and Photophysics in Silica-Based Materials: Ultrafast and Single Molecule Spectroscopy Observation

“…In the DSSC’s configuration with N3 sensitizer, this material results in a photocurrent density of 45 μA/cm 2 . Further studies using a similar concept were performed with the organic dye TPC1 (Scheme ) as the sensitizer . Two kinds of Ti-doped mesoporous structures were used: titanium atoms incorporated into the previously prepared MCM41 framework by the grafting method and small titania nanoparticles used as one of the components in building the hexagonal mesoporous structure of SBA15 …”

“…The subsequent contribution of the same group was devoted to Ti-modified mesoporous molecular sieves. 563 The material with isolated titanium atoms forming part of a framework of mesoporous MCM41 silica (Ti/MCM41) has a high surface area of approximately 880 m 2 g −1 . In the DSSC's configuration with N3 sensitizer, this material results in a photocurrent density of 45 μA/cm 2 .…”

“…Further studies using a similar concept were performed with the organic dye TPC1 (Scheme 4) as the sensitizer. 563 Two kinds of Ti-doped mesoporous structures were used: titanium atoms incorporated into the previously prepared MCM41 framework by the grafting method and small titania nanoparticles used as one of the components in building the hexagonal mesoporous structure of SBA15. 564 Figure 62A presents a schematic visualization of the two structures, showing titania domains approximately of 2 nm in size in the TiMCM41 grafted material.…”

Control of Photocurrent Generation in Polymer/ZnO Nanorod Solar Cells by Using a Solution-Processed TiO2 Overlayer

“…It is well-known that the morphology and the nanostructure of the different phases that form the devices have an important influence on the final properties. − For example, in the case of the inorganic phase, there are many examples of different kinds of metal oxide nanostructures that have been successfully integrated in devices, for instance, nanoparticles, nanorods, , nanotubes, or mesoporous networks, giving in many cases an improved photovoltaic effect relative to that of simple layered structures. , …”