Introduction

The invention concerns a method for the production of nanometric-size powders of elementary boron, in the amorphous state and/or optionally homogeneously doped. Our method is suitable for the industrial production of doped boron: the nanopowders obtained have improved properties, due to the controllable formation of optimal defects at short and medium range into the crystal lattice. The method is cheap, uses standard processes and allows the production of large amount of nano-powders per batch.

Technical features

Doped boron, indispensable for increasing the performance of superconductors, is not commercially available, and the doping process must be successively done in laboratory by adopting not environmentally friendly, expensive, and hazardous processes, both for the technicians and the environment.

Our method solves such problems and includes the following steps:

1. dissolving an oxidized Boron precursor compound in a solvent (during this step a doping agent can be added if required).
2. freezing the solution into a cryogenic liquid and by sublimation transforming it in a finely divided particulate form. Solvent (water) is removed by freeze-drying process and nanostructured Boron precursor is obtained.
3. reduction with a reducing agent, to obtain elementary amorphous boron in nano-sized powder form, amorphous can be turned into crystalline.

Since the use of boron as a superconducting material (MgB2) saves energy in the transport of power current and favors the diffusion of renewable energies, this project is aimed at decreasing the anthropic impact for a greener future.

Possible Applications

• Superconducting wires;
• Air-bags triggers;
• Neutron absorbers;
• Semiconductors, alloys, glasses;
• Abrasives;
• Refractory materials;
• Propellant for rockets;
• Bleaches, catalysers, disinfectants.

Advantages

• High degree of purity (95-98%);
• Nanostructured and amorphous powders, optionally intrinsically doped;
• Homogeneity of doped boron powders;
• Applicability to different boron precursors;
• Large amount of product per batch.