GaN nanodiscs embedded in nanowires as optochemical transducers

摘要

The photoluminescence (PL) response of GaN/AlGaN nanowire heterostructures (NWHs) to hydrogen and oxygen between room temperature and 300 °C is reported. Exposure of Pt-coated NWHs to H_2 leads to an increase of the PL intensity attributed to the suppression of surface recombination by local dipole fields of adsorbed atomic hydrogen. When exposed to O_2, uncoated NWHs show a decrease in PL intensity that is assigned to enhanced non-radiative recombination. The detection limits are below 5ppm at 150 °C.