The Influence of the Ammonolysis Temperature on the Photocatalytic Activity ofβ-TaON

[摘要] Phase-pure tantalum oxynitride (β-TaON) powders were synthesized by thermal ammonolysis of Ta2O5powders. X-ray diffraction revealed an enlargement of the unit cell and an increase of the crystallite size with increasing ammonolysis temperature. Scanning electron microscopy showed reduced particle sizes forβ-TaON synthesized at 800 and900∘Ccompared to the precursor oxide. With increasing nitridation temperature the Brunauer-Emmett-Teller surface area was reduced and the nitrogen content increased. UV-Vis spectroscopy showed a bandgap energy of 2.6–2.4 eV. The highest oxygen evolution rate of 220 μmol·g−1·h−1was achieved forβ-TaON synthesized at800∘C. The factors determining the photocatalytic activity ofβ-TaON powders were found to be the specific surface area and defects in theβ-TaON.

[学科分类] 物理化学和理论化学