P-n heterojunction

O Regan B, Schwartz DT (1996) Efficient dye-sensitized charge separation in a wide-band-gap p-n heterojunction. J Appl Phys 80 4749 754... 

O Regan B. and Schwartz D. T. (1996), Efficient dye-sensitised charge separation in a wide-bandgap p-n heterojunction , J. Appl. Phys. 80, 4749-4754. 

Rost C., Sieber I., Siebentritt S., Lux-Steiner M. C. and Konenkamp R. (1999a), Spatially distribnted p-n heterojunction based on nanoporous Ti02 and CuSCN , Appl. Phys. Lett. 75, 692-694. 

Hu W. and Matsumura M. (2004), Structure and thickness dependence of p-n heterojunction solar cells based on copper phthalocyanine and perylene pigments , J. Phys. D Appl. Phys. 37, 1434—1438. 

Currently, much work is devoted to the synthesis of conducting polymers for use in a variety of applications. Polyacetylene, the prototype conducting polymer, has been successfully demonstrated to be useful in constructing p-n heterojunctions, (1) Schottky barrier diodes, (2,3) liquid junction photoelectro-chemical solar cells, (4) and more recently as the active electrode in polymeric batteries. (5) Research on poly (p-phenylene) has demonstrated that this polymer can also be utilized in polymeric batteries. (6)... 

FIGURE 22.22 Polarization curves for localized corrosion of a photoexcited p-n heterojunction electrode of GaAs in 0.5 kmol m-3 sulfuric acid solution [15] ta(ph) = anodic photo-dissolution current and lc(ph) = cathodic photo-hydrogen current. 

Key words carbon nanotubes/metal oxides gas sensor, MOX/CNT composites, p-n heterojunctions, hybrid sensor, sensing part for e-nose. 

From many studies, it was found that CNTs are embedded in the MOX layer leading to the formation of p-n heterojunctions. Therefore, there are... 

The unique structure and electronic properties of CNTs provide a tremendous potential for construction of CNTs and MOX hybrid materials in the field of gas-sensing applications. Advantages for mixing CNTs in metal oxides for gas sensors are the reduction of operating temperature and enhancement of sensitivity and selectivity due to the amplification effects of p-n heterojunctions with the gas reaction, formation of nanochannels for gas diffusion, high specific surface area, and increase of charge carrier on the surface. As a result of these advantages, the hybrid CNT/metal oxide gas sensor may be used instead of the popular commercial metal oxide gas sensors (such as TGS gas sensors) in the near future. 

With the development of organic semicondnctors which support electron or hole transport (in analogy of p- and n-type inorganic semiconductors) bilayer type p-n heterojunction devices have been constructed. In the case when organic p- and n-type materials are deposited consecutively in two layers we get lateral heterojunction devices which mimic classical p-n junction junction solar cells based on silicon. The first such cell was designed by Tang and pnb-lished in 1986 (Fignre 3)." Copper phthalocyanine was utilized as electron donor (p-type) material, whereas pery-lene derivative was nsed as electron acceptor connterpart (n-type material). 

To yield complex multicomponent architectures with distinct functional properties, such as p-n heterojunctions for use in nanosized electronics and photocatalysis similar to the photosynthetic system in nature, it is crucial to exactly place the components at specified positions or in ordered clusters, and to control the stability of this organization in time. By considering the mixing of two different... 

Figure 3 Gelators 3 and 4 and a schematic representation of the self-sorted gel with p-n heterojunctions (indicated as circles) between the two different fibers.

A p-n heterojunction between two separate domains assembled on top of each other was recently prepared by... 

Figure 17 Molecular structure of 46 and 47, forming p-n heterojunction by sequentiai spin coating on a surface. (A) Differentiai interference contrast microscopy of the bilayer during the thermal armealing. (B) Schematic representation of the columnar liquid...

Chen Y, Yu L, Feng D, Zhuo M, Zhang M, Zhang E, Xu Z, Li Q (2012) Superior ethanol-sensing properties based on Ni-doped Sn02 p-n heterojunction hollow spheres. Sens Actuators B 166-167 61-67... 

A p-n-heterojunction type device can be fabricated on the basis of the junction formed between poly(pyrrole) and PT derivatives (e.g. PT or PMT) [784]. A PODT/Cfio junction device with a photo-induced charge transfer between PODT and Cgo is shown in Fig. 22 [449]. Rectifying bilayer electrodes with sequential bilayer structures are prepared from any pair of PBT/poly(pyrrole) and poly(3-bromothiophene)/poIy(pyrrole) by anodic electropolymerization on platinum electrodes [785]. 

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