Titanium dioxide solar cells

The most common oxidation state of titanium is +4, in which the atom has lost both its 4s-electrons and its two 3d-electrons. Its most important compound is tita-nium(IV) oxide, Ti02, which is almost universally known as titanium dioxide. This oxide is a brilliantly white (when finely powdered), nontoxic, stable solid used as the white pigment in paints and paper. It acts as a semiconductor in the presence of light, and so it is used to convert solar radiation into electrical energy in solar cells. 

Polycrystalline GaN UV detectors have been realized with 15% quantum efficiency [4], This is about 1 /4 of the quantum efficiency obtained by crystalline devices. Available at a fixed price, however, their increased detection range may well compensate their lack in sensitivity. Furthermore, new semiconductor materials with a matching band gap appear as promising candidates for UV detection if the presumption of the crystallinity is given up. Titanium dioxide, zinc sulfide and zinc oxide have to be mentioned. The opto-electronic properties and also low-cost production processes for these compound semiconductors have already been investigated to some extent for solar cell applications [5]. 

The antenna effect as it is found in natural photosynthetic systems is an attractive tool for increasing light absorption of solar cells. Some of the work done on dye sensitization of polycrystalline titanium dioxide shows aspects of antenna behavior [76,83-87]. Most of the problems in the systems where an electron is injected into the semiconductor arise in the regeneration process of... 

Kay A (1996) Low cost photovoltaic modules based on dye sensitized nanocrystalline titanium dioxide and carbon powder. Solar Energy Mater Solar Cells 44 99-117 Wang X, Zhi L, Muellen K (2008) Transparent, conductive graphene electrodes for dye-sensitized solar cells. Nano Lett 8 323-327... 

Titanium dioxide (Ti02) has been attracting much attention for its important role in water photo-oxidation and photocatalyst, as well as a base material for dye-sensitized solar cells. A number of studies have been conducted on the mechanisms of interfacial photo-anodic reactions but the reported mechanisms still remain sketchy, and the detailed molecular mechanism has not yet been clarified. The main reason for confusion may arise from the possibility that the reaction mechanism depends on detailed chemical structures of the electrode surface. This implies that studies with well-defined surfaces are of key importance. 

The nanocrystalline solids are metal oxides, especially titanium dioxide [54-58], Various dyes are used. Transition metal complexes such as (65) and (66) have broad absorption bands and allow the harvesting of a large fraction of sunlight [54,58], Fluorescent dyes are also used, such as Eosin-Y (67) [57], Dye-sensitized nanocrystalline solar cells are now giving efficiencies in excess of 10% [54,58], compared to just 1 % ten years ago [3],... 

PlO-14 Titanium dioxide is a wide-bandgap semiconductor that is showing promise as an insulating dielectric in VLSI capacitors and for use in solar cells. Thin films of T102 are to be prepared by chemical vapor deposition from gaseous titanium tetraisopropoxide (TTIP). The overall reaction is... 

Use Hardener for platinum and palladinum in jewelry, electrical contact alloys, catalyst, medical instruments, corrosion-resistant alloys, electrodeposited coatings, nitrogen-fixing agent (experimental), solar cells (experimental) the oxide is used to coat titanium anodes in electrolytic production of chloride the dioxide serves as an oxidizer in photolysis of hydrogen sulfide. 

Wahi A. and Konenkamp R. (1992), Interface characterization amorphous silicon on titanium dioxide. Towards a solid-state sensitization solar cell , Proc. 11th. Photovoltaic Solar Energy Conf., Harvard Academic Publishers. 

In 1977 Schrauzer and Guth published a seminal communication [1] in which the photocatalytic synthesis of ammonia from nitrogen and water was described. The process involved irradiation with UV-visible light in the presence of a titanium dioxide-based photocatalyst (Section II.A) and was described as the basis for a prototype solar cell for photochemical ammonia synthesis [2]. The photocatalytic process is represented by reaction 1. 

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