Fabrication of vertically aligned single-crystalline lanthanum hexaboride nanowire arrays and investigation of their field emission

High-quality, uniform, one-dimensional (1D) lanthanum hexaboride (LaB6) nanostructures with different morphologies (for example, sparse or dense nanoneedles, or nanorods and nanowire arrays) were fabricated through an effective, easily controlled, one-step, catalyst-free chemical vapor deposition process. The morphologies, structures and temperature-dependent field emission (FE) properties were systematically investigated. FE measurements at room temperature (RT) showed that LaB6 nanowire arrays possess the best FE characteristics among all 1D LaB6 nanostructures, with a low turn-on electric field (Eto, 1.82 V μm−1), a low threshold electric field (Ethr, 2.48 V μm−1), a high current (5.66 mA cm−2 at 2.92 V μm−1) and good stability (at a testing time of 1000 min, fluctuations were