Influence charges

The efficiency of such photocatalysts in influencing charge separation will depend sensitively on the dynamics of interfacial charge transfer, particularly as compared with the rate of electron-hole recombination. The presence of trap sites and dopants will profoundly influence the latter rates, and quantum yields attainable on such heterogeneous suspensions will clearly reflect such structural variants. A trapped carrier will possess a longer lifetime consistent with an enhanced ability to participate in charge transfer with a desired adsorbate. 

Haque S. A., Tachibana Y., Willis R. L., Moser J. E., Gratzel M., King D. R. and Durrant J. R. (2000), Parameters influencing charge recombination kinetics in dye-sensitized nanocrystalline titanium dioxide films , J. Phys. Chem. B 104, 538-547. 

Fig. 12.13 An organic thin-film field-effect transistor, schematic. The current Id in a weakly semiconducting organic film (black) between two electrodes S (source) and D (drain) can be controlled by the gate (G) voltage Vc- The latter influences charge carriers capacitively in a thin layer of the...

The primary species involved in charge transport are thus electrons in the oxide film and the reduced and oxidized forms of the hole conductor. The extremely high surface area means that interfacial electron transfer reactions and electrostatic interactions between species in the two conducting media are particularly important. In addition, the following secondary species may influence charge transport ... 

In general terms, coupled mechanistic schemes are described by the letters E (electrochemical) and C (chemical). The order in which they are written denotes the order in which the processes occur. Thus an ECE mechanism describes a process in which an electrochemical step is followed by a chemical step, which is then followed by an electrochemical step. A chemical step is a step where no electron transfer to or from the electrode takes place. Such a step does not by itself produce a charge flow into or out of the electrode and thus is not directly observable by an external measuring circuit. It may, however, influence charge flow because of other steps in the mechanism, which can be detected indirectly. The chemical step is not directly influenced by the electrode potential. An electrochemical step on the other hand involves electron flow to and from the electrode and as such produces a flow of charge that can be monitored by the external measuring circuit. 

Study of the role of counterions and solvents on ion-pairing effects which influence charge-transfer reactions of donor-acceptor model compounds has continued with a study of bicyclooctatetraenyl dianion (1 )." Rate constants have been determined, by NMR spectroscopy, for bond shift (A bs) and intramolecular charge transfer (fccr) in the alkali metal salts (1 /2M+) in THF-solvent-separated ion pairs (SSIPs) (l /2Na+) is the first example of a sodium salt of a dianion to undergo charge transfer by SSIPs and it is surmized that formation of the sodium-bridged CIP transition structure is relatively unfavourable. 

The arrangement of the composite sample with integrated piezoelectric transducer represents a bending bar. If this sample is deformed by a vertically applied force F, the integrated transducer is deformed, thus producing charges on the surface due to the piezoelectric effect. This in turn influences charges on two electrodes, positioned on the upper and lower side of the transducer. 

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