Spectrally resolved thermoluminescence in UV excited hexagonal boron nitride nanopowder

Thermally stimulated luminescence (TSL) excitation and emission processes in h-BN nanopowders after UV irradiation were studied. TSL showed the highest response within the 5.4 eV band. 3.0 and 3.9 eV bands, resulting from the radiative donor-acceptor recombination between the electron (1B-H ON-centers) and the hole traps (CN-center), were found. TSL curves quantitative analysis in the context of general order kinetics was made. It was shown that 1B-centers had 0.85±0.05 eV activation energy and were responsible for the TSL peak at 350±10 K. Band structure for TSL excitation and emission mechanisms in h-BN nanopowder was suggested.