Synthesis of niobium(iv) carbide nanoparticles an alkali-molten-method at a spatially-limited surface of mesoporous carbon.

One-pot synthesis of niobium carbabide (NbC) nanoparticles with 30-50 nm was achieved a rationally designed novel alkali-molten salt method using niobium oxide (NbO), potassium carbonate (KCO), and mesoporous carbon (MPC). In this reaction, potassium niobate (KNbO) was produced as an intermediate and carbonization of KNbO proceeds at a spatially limited external surface encompassed by the mesopores of MPC due to the repulsive characteristics of ionic KNbO toward hydrophobic MPC, which affords the size-controlled NbC nanoparticles with a narrow particle distribution. The particle sizes tended to become smaller as the pore sizes of MPCs or the temperature on the calcination under the nitrogen stream decreased.