Boric acid B(OH)(3) has been thermally nitrided under flowing ammonia
into a boron oxynitride. This reaction has been followed using various
structural techniques: X-ray photoelectron spectroscopy (XPS), infrar
ed spectroscopy (IR), X-ray diffraction and chemical analyses. Reactio
n of boric acid with ammonia began at 155 degrees C. The weight percen
t of nitrogen increases with the temperature of the pyrolysis process.
Formation of B-N bonds is observed at 400 degrees C by infrared spect
roscopy. Two boron species are observed by XPS and identified as boron
linked mostly to oxygen atoms and as boron linked mostly to nitrogen
atoms, denoted BOx and BNx, respectively. The intensity of the BNx sig
nal increases with the pyrolysis temperature.