부산대학교 도서관

Carbon nanotubes (CNTs) are the most famous cold cathodes for display technology. However, graphene and other two dimensional carbon nanostructures and advanced II-VI semiconductor nanostructures are strongly emerging as strong competitors challenging the well established performance of CNTs in this field. Hence several technologies to improve field emission (FE) properties of CNTs are being developed. Here we report a facile technique to improve the cold emission performance of multiwalled CNTs (MWCNTs) by coating the same with chalcogenide semiconductor. MWCNT thin films were synthesized via chemical vapor deposition (CVD) technique and the same was coated by cadmium sulfide (CdS) nanoparticles via radio frequency magnetron sputtering technique. The pure and coated thin films were characterized by Fourier transform infrared spectroscopy and Raman spectroscopy to confirm presence of CdS on CNT surfaces. X-ray photoelectron spectroscopy revealed the compositional and valance state information of the as prepared samples. Field emission scanning electron microscopy and high resolution transmission electron microscopic studies were carried out to obtain information regarding morphology and nanocrystallinity of the CNTs and the coated CdS nanoparticles. Field assisted electron emission of pristine CNTs developed significantly with improved turn-on field and very high current density by CdS nanoparticle coating.