Hannes Kind

Nanowire Ultraviolet Photodetectors and Optical Switches

no attention has been given to the photoconducting properties of nanowires despite the exciting possibilities for use in optoelectronic circuits. Here, we show the possibility of creating highly sensitive nanowire switches by exploring the photoconducting properties of individual semiconductor nanowires. The conductivity of the ZnO nanowires is extremely sensitive to ultraviolet light exposure. The light-induced conductivity increase allows us to reversibly switch the nanowires between “OFF” and “ON” states, an optical gating phenomenon analogous to the commonly used electrical gating. [2,3,10]

FIELD EMISSION FROM CARBON NANOTUBES: THE FIRST FIVE YEARS

Abstract Carbon nanotubes, a novel form of carbon discovered in 1991, have been rapidly recognized as one of the most promising electron field emitters ever since the first emission experiments reported in 1995. Their potential as emitters in various devices has been amply demonstrated during the last five years, and recent developments of production techniques are likely to trigger future applications. This report reviews the state of the art of the current research on the electron field emission properties of carbon nanotubes and surveys their ability to provide single or multiple electron sources.

PATTERNED FILMS OF NANOTUBES USING MICROCONTACT PRINTING OF CATALYSTS

change in the vibrational structure of the PL spectrum were effected by MWNTs. The reduction of the PL efficiency can be a result of energy transfer and partial hole transfer from PPV chains to MWNTs, together with scattering and absorption by MWNTs. Using the composite, photovoltaic devices have been fabricated by employing MWNT as a hole-collecting electrode. We obtained good quantum efficiency (1.8 % at 2.9±3.2 eV), about twice that of the standard ITO device. It is considered that the high efficiency arises from a complex interpenetrating network of PPV chains with MWNTs and the relatively high work function of the MWNT film. The present results suggest the possible application of carbon nanotubes as a new interesting electrode material in macroscale devices.