Fabrication and field emission properties of boron nanowire bundles

We have successfully synthesized large-scale crystalline boron nanowire bundles (BNBs) by chemical vapor deposition method. Fe3O4 nanoparticles were used as catalysts spreading on ceramic substrate during the reaction process. The bundles consisted of many thin boron nanowires with a mean diameter of about 25 nm and a length of several micrometers. In addition, boron nanowires are single crystals with an α-tetragonal structure and grow along [0 0 1] orientation. These nanowires have a surface electron affinity of 3.76 eV and a work function of 4.54 eV. A turn-on field of 5.1 V/μm and a threshold field of 10.5 V/μm were found in the nanowire bundles, and stable field emission was recorded at the same time.