Photovoltaic cell photoelectrochemical cells

Badawy,W.A. Photovoltaic and Photoelectrochemical Cells 30 Based on Schottky Barrier Heterojunctions... 

A common feature of the various RCs is the trigger of the phottxhemistry by solar energy, but there are differences in the way they convert energy and consequently on their potential application for the building of biochips, biosensors, photovoltaic and photoelectrochemical cells, holographic memory etc. 

Metal oxide electrodes have been coated with a monolayer of this same diaminosilane (Table 3, No. 5) by contacting the electrodes with a benzene solution of the silane at room temperature (30). Electroactive moieties attached to such silane-treated electrodes undergo electron-transfer reactions with the underlying metal oxide (31). Dye molecules attached to sdylated electrodes absorb light coincident with the absorption spectmm of the dye, which is a first step toward simple production of photoelectrochemical devices (32) (see Photovoltaic cells). 

Gutierrez MT, Salvador P (1987) Photoelectrochemical characterization and optimization of a liquid-junction photovoltaic cell based on electrodeposited CdSe thin films Influence of anneaUng and photoetching on the physical parameters determining the cell performance. Sol Energy Mater 15 99-113... 

Byvik CE, Smith BT, Reichman B (1982) Layered transition metal thiophosphates (MPX3) as photoelectrodes in photoelectrochemical cells. Sol Energy Mater 7 213-223 Lincot D, Gomez Meier H, Kessler J, Vedel J, Dimmler B, Schock HW (1990) Photoelectrochemical study of p-type copper indium diselenide thin films for photovoltaic... 

Dhere, N.G. and Jahagirdar, A.H., Photoelectrochemical water splitting for hydrogen production using multiple bandgap combination of photovoltaic cell and thin-film-photocatalyst,... 

Photoelectrochemical semiconductor cells are used to convert photon energy into chemical substances or into electricity, the former is a photodectrolytic cell and the latter is a photovoltaic cell. A photoelectrochemical semiconductor cell consists of either a pair of metal and semiconductor electrodes or a pair of two semiconductor electrodes. 

The final two chapters deal with applications (in the scientific as well as commercial sense) of CD films. As already mentioned, photovoltaic cells is the one subject that has given CD a push in the last decade, while photoelectrochem-ical cells was probably the main driving force for such studies in the decade before that. Chapter 9 deals with Photovoltaic and Photoelectrochemical Properties. 

Solar energy conversion and photovoltaic devices encompass one of the most active applied topics of research in this area191. Thus, photoelectrochemical cells based on electrodes (Sn02, Pt) coated with tetrapyrroles have been studied for a long time191-194. Most studies were performed with phthalocyanines due to their stability and wide range of redox... 

The formation of amorphous silicon films by electrodeposition from non-aqueous solutions have also been studied [18, 19]. For example, a flat homogeneous silicon film of about 0.25 pm thick can be deposited from 0.2 M SiHCl3-0.03 M Bu4NBr-THF bath on the cathode of Pt, Au, Cu, GC, ITO, etc., although small amounts of impurities (O, C, Cl) are contained. Their use in photovoltaic or photoelectrochem-ical solar cells are promising, although there are still many problems to be solved. 

This volume, based on the symposium Photoeffects at Semiconductor-Electrolyte Interfaces, consists of 25 invited and contributed papers. Although the emphasis of the symposium was on the more basic aspects of research in photoelectrochemistry, the covered topics included applied research on photoelectrochemical cells. This is natural since it is clear that the driving force for the intense current interest and activity in photoelectrochemistry is the potential development of photoelectrochemical cells for solar energy conversion. These versatile cells can be designed either to produce electricity (electrochemical photovoltaic cells) or to produce fuels and chemicals (photoelectrosynthetic cells). 

Another interesting work is the recent report by Licht et al [72, 75, 94]. Although the system they studied was not a strict photoelectrochemical one, since the photovoltaic system was separated from the water electrolyser, their study is of general interest for the water oxidation field. The photovoltaic cell was connected to a water splitter catalyst system of considerably larger area than the solar cell. With this design, it was possible to combine a high solar cell efficiently with a low photocurrent density over the electrolyzer (jph = 0.44 mA/cm2), which minimized the overpotential needed for water oxidation. An overall efficiency as high as 18.3% was obtained. 

Semiconductors have proven to be very important factors in the photovoltaic conversion of solar radiation into electric energy. They can also be used as photoelectrodes in photoelectrochemical cells producing power or fuels, and in photocatalytic reactions of high specificity, though these applications are still at the experimental stage. 

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