Thermal stability of UV light emitting boron nitride nanowalls

Thermal stability of the boron nitride nanowalls (BNNWs) obtained by plasma-enhanced chemical vapor deposition (PECVD) from borazine (B3N3H6'), in oxidative (air) and inert (argon) atmospheres was studied. The annealing caused the sample surface oxidation with the replacement of nitrogen atoms by oxygen in the hexagonal h-BN structure, which led to a destruction of the layered structure. Strong UV light emission with a broad band ranging from 300 to 500 nm at room temperature was detected. Changes in composition, morphology, structure and luminescent properties of the samples before and after annealing in different atmospheres are reported. The BNNWs obtained at 700 degrees C from B3N3H6-NH3 mixture were stable at the temperatures up to 1100 degrees C and improved their luminescence properties after annealing. Due to high thermal stability and luminescence the present BNNWs may find applications in the optical devices operating at high temperatures. (C) 2016 Elsevier Ltd. All rights reserved.