Charge Emissions from the Plasma Photogerated in Channels of SWNTs

Abstract

Summary form only given. In recent years it has been reported that nanomaterials such as single-walled carbon nanotubes (SWNTs), silicon nanowires, and polyaniline nanofibers could have an abnormal photothermal effect under a camera flashlight. We have also investigated the visible-light-induced split of water confined in channels of SWNTs. In this paper, we will focus on the charge emission phenomena when the SWNT sample in ultrahigh vacuum is irradiated with a fast light exposure. We designed a special experimental procedure to monitor the positive and negative charges launched from the irradiated SWNT sample. Indeed, both positive and negative charge emissions have been recorded. Originally, such phenomena could only be observed occasionally, but now we can definitely obtain the charge emissions for each time of fast-light exposure. We found that the charge intensity is related to the residual gas adsorption, the collecting voltage, the external magnetic field, and the intensity of the input light. Some plasma characteristics of the photogenerated charges have been determined. We suppose that the nano-confinement of the adsorbed residual gases in the channels of SWNTs would play a key role in such phenomena