Excellent Field-Emission Performances of Neodymium Hexaboride (NdB6) Nanoneedles with Ultra-Low Work Functions

High‐quality NdB6 nanostructures with a low work function are successfully synthesized via an one‐step catalyst‐free chemical vapor deposition process. Field emission properties of these nanostructures (curve nanowires, short‐straight nanorods, long‐straight nanowires, and nanoneedles) are systematically investigated and found to be strongly affected by the tip morphologies and temperatures. The nanoneedles with sharp tips demonstrate the lowest turn‐on (2.71 V/μm) and threshold (3.60 V/μm) electric fields, as well as a high current density (5.37 mA/cm2) at a field of 4.32 V/μm in comparision with other nanostructures. Furthermore, with an increase in temperature from room temperature to 623 K, the turn‐on field of the nanoneedles decreases from 2.71 to 1.76 V/μm, and the threshold field decreases from 3.60 to 2.57 V/μm. Such excellent performances make NdB6 nanomaterials promising candidates for application in flat panel displays and nanoelectronics building blocks. High‐quality low‐work‐function NdB6 nanostructures with different morphologies, e.g., curved nanowires, nanorods, nanowires, and nanoneedles, are successfully fabricated via a catalyst‐free chemical vapor deposition process. The field‐emission measurements are investigated systematically, and the field‐enhancement factor, turn‐on, and threshold field changes are analyzed as a function of morphology and temperature. These systematic experiments should facilitate NdB6 nanomaterial application in novel field‐emission devices.