Polyciystalline

Smooth Polyciystalline Platuuun Electrodes 3J3 d Electrochemical Studies... 

Fig. 3-11 Applied potential profile and current response of polyciystalline platinum electrode in 3 M H2SO4,0.1 M CH30H. 

Fig. 3- 1 In situ infrared spectra of polyciystalline platinum electrode at 600 mV and lOSOmV in 0.5 M H2SO4 with 1M CH3OH. Reference state lOSOmV.

The use of polycrystalline La doped SrTiOs as a photoanode has also been investigated [31]. La is considered an appropriate dopant because of its stability in trivalent state and the similarity of the ionic radii for Sr (1.40 A) and La " (1.32 A), which ensures its incorporation at Sr sites. Doping leads to the formation of a new energetic deep donor sub-level (Ti sd) in the band gap, thereby shifting its response towards the visible region. Similarly doping of polyciystalline Ti02 has shown an increase... 

Lindquist SE, Lindgren A, Ning ZY (1985) On the origin of the bandshifts in the action spectra of polyciystalline TiOa electrode prepared by thermal oxidation of titanium. J Electochem Soc 132 623-631... 

Hodes G, Manassen, Cahen D (1976) Photoelectrochemical energy conversion and storage using polyciystalline chalcogenide electrodes. Nature 261 403-404... 

Single crystal silicon (sc-Si), polyciystalline silicon (p-Si), and amorphous silicon (a-Si) can all be used to make solar cells, with fabrication cost and device photoconversion efficiencies decreasing as one moves from single-crystal to amorphous materials. Various properties of these materials are summarized in Table 8.1. Other relatively common solar cell materials include gallium arsenide (GaAs), copper indiirm diselenide (CIS), copper indium-gallium... 

Experimental parameters were obtained from the adsorbance of bisulfate ions on polyciystalline electrodes using a radiotracer technique slightly different from that described in the text, where the working electrode is placed on top of the scintillator. These values are listed in Table P.l. 

While the magnetic properties of the compounds with light R atoms are rather complex, ferromagnetic ordering has been deduced from magnetization measurements on polyciystalline samples for Gd and the other heavy R atoms. In the case of GdCuAl the... 

Ullal, H.S., K. Zweibel, and B. von Roedem. 2002. Polyciystalline Thin Film Photovoltaics Research, Development, and Technologies. Paper presented at 29th Institute of Electrical and Electronics Engineers Photovoltaic Specialists Conference (IEEE PVSC), New Orleans, La., May... 

Solid electrolytes can be amorphous, polyciystalline, or single-ciystal. 

Kontani et al. (1995, 1996) measured hole mobilities of vapor-deposited TiOPc. The transit times were derived from photocurrent transients in double logarithmic representation. In agreement with the work of Ioannidis and cowoikers with ClAlPc, the results showed that the mobilities were strongly dependent on the substrate temperature during the vapor deposition. For substrate temperatures between -160 to 160 C, the room temperature mobility increased from 6.0 x 10-6 to 8.0 x 10-5 cn /Vs. The authors attributed this to an increase in film crystallinity. Films prepared at low temperatures were largely amorphous while those prepared at high temperatures were mainly polyciystalline. 

Nespurek et al. (1981) and Slavinska et al. (1983) measured hole mobilities of amorphous, polyciystalline, and spherulitic layers of ethyl 2,5-di(anilino)-terephthalate and its oligomer. The transport was strongly influenced by trapping. In the amorphous phase, the trap depth was approximately 0.50 eV. The presence of crystalline or spherulitic domains in the amorphous phase form-... 

Mycielski and Lipinski (1978), Kania et al. (1979), Mycielski et al. (1983), and Bak et al. (1995) reported electron and hole mobilities of vapor-deposited polyciystalline layers of various hydrocarbons CuPc, coronene, / -terphenyl, p-quaterphenyl, and tetracene. The mobilities were in the range of 10-3 to 10 5 cm2/Vs and inversely proportional to the field. A mobility with an E-l field dependence is equivalent to a field-independent drift velocity. 

Fig. 1. XPS spectra of the initiators grafted onto polyciystalline titanium upper half general spectra, lower half core level Cls spectra before (a) and aft grafting of ACTP (b)and ACTU (c).

The pre-reacted substance is ground and formed after adding an organic binder. The firing temperatures lie in the range 1000-1400 X both temperature and atmosphere have to be chosen with respect to the stability of the substances. With the exception of hard ferrites the firing is taken to complete sintering. The properties of the product depend on the character of the polyciystalline structure. A coarser... 

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