Effect of functionalization on the electrical properties of laser-structured hybrid carbon nanomaterials

Background and Objectives: An urgent task of field emission electronics is to reduce the operating voltage in order to obtain an emission current of a given density. To solve this problem, an emitter with a low work function is needed. Carbon nanomaterials are promising candidates for the role of field emitters; however, to reduce the work function of electrons from these nanomaterials, it is necessary to functionalize their surface with other nanostructures with a low work function. In this work, we experimentally studied the effect of functionalization of lanthanum hexaboride (LaB$_6$) with nanoparticles on the electrical properties of nanomaterials based on an array of carbon nanotubes (CNTs). Materials and Methods: Using the developed technology of laser exposure, a hybrid nanomaterial was created based on a vertical array of CNTs functionalized with LaB$_6$ nanoparticles. Pulsed laser action on an array of CNTs with an energy density of 0.15 J/cm$^2$ made it possible to shorten, align, and structure the upper ends of the nanotubes perpendicular to the substrate. Results: The effect of the formation of a hybrid nanostructure by binding LaB$_6$ nanoparticles to the CNT surface has been experimentally established. Registration of the emission current-voltage characteristics of hybrid nanomaterials has shown a decrease in the total work function of the hybrid nanomaterial by 78$\%$ after functionalization with LaB$_6$ nanoparticles. Conclusion: Based on the results obtained, it is predicted that CNT+LaB$_6$ hybrid nanostructures have a great potential for application as nanomaterials for field emission electronics.