Optical properties of oxynitride powders

Processing of dielectric oxynitride perovskites for powders, ceramics, compacts and thin films

“…A mixture of oxides and carbonates can also be used directly for nitridation in NH 3 5a,8 . For example, a mixture of BaCO 3 and Ta 2 O 5 in a molar ratio of 2 was nitrided at 950 °C to obtain BaTaO 2 N 8,21e . In addition, single-crystal oxides have also been used as the precursor to produce oxynitrides on the oxide surface 23 .…”

“…As an expedient method, the sintering of oxynitrides in ammonia was featured by preparation of a green body under high pressure (e.g., 760 MPa), and subsequent heat treatment at a moderate temperature in NH 3 . Although considerable porosity remained, the pellet had sufficient mechanical strength and electrical conductivity pathways necessary for characterization.…”

“…Oxynitrides that crystallize in the perovskite structure are emerging in applications such as photocatalysis and as harmless pigments 2 . These oxynitride perovskites absorb visible light because they have a more covalent nature than oxides 3 . The anion order is an interesting structural feature that appears with oxynitride perovskites, which have both oxide and nitride anions together in the compound 2a,4 .…”

“…The local anion order was described as forming a three-dimensional disordered zigzag Ta-N chain 5a,19 . The presence and thermal stability of anion order in the SrTaO 2 N and LaTaON 2 oxynitride perovskites was investigated using high resolution powder neutron and electron 2 | Dalton Trans., 2012, 00, [1][2][3] This journal is © The Royal Society of Chemistry 2012 diffraction 20 . The anion order was maintained up to 1100 °C and was expected to be stable up to significantly higher temperatures greater than 2000 °C.…”

“…However, a flux was added to accelerate the nitridation 2c,25b . A series of pure Ca 1−x Eu x Ta(O,N) 3 was successfully synthesized in the entire range of Ca/Eu compositions via SCR, which demonstrates its advantage over SSR 28,30 .…”