Thin-walled B-C-N ternary microtubes: from synthesis to electrical, cathodoluminescence and field-emission properties

Microtubes with nanoscale sidewalls, benefiting from their large internal space, can find wide potential applications in microreactors, microfluidic devices, drug delivery systems, etc. We report on the synthesis of thin-walled B-C-N ternary microtubes based on a modified vapor-liquid-solid (VLS) and template self-sacrificing process. The BCN microtubes have unique structures with diameters in the microscale range and wall-thicknesses in the nanoscale range. In situ electrical measurements indicate that the BCN microtubes have a semiconducting behavior with enhanced conductivity. The electrical properties of the microtubes can be tailored by successful C doping. A strong broad UV band is observed from the microtubes, which can be assigned to the impurity and/or defect-related emission (IDRE). Field-emission measurements show that after C doping, the resultant BCN microtubes have greatly improved field-emission characteristics compared with pure BN microtubes.