Photoactive tetragonal bismuth oxide powder with different semiconducting characteristics was synthesized from Bi-pellets by flame spray oxidation. The effect of feedstock particle size and standoff distance (SOD) on the physical properties of β-Bi₂O₃ keeping constant the fuel/oxygen ratio is here reported. The flame spray oxidized powder was collected either from evaporated or in-flight particles quenched in water. The combination of flame spray processing parameters led to different β-Bi₂O₃ phase contents, oxidation characteristics, size distribution (nanometric and micrometric sized), morphology, and optical properties of the sprayed powder. The highest micrometric β-Bi₂O₃ content quenched in water was obtained at a SOD of 30 cm using a particle size distribution of 12-60 μm of Bi-feedstock. The obtained powder from in-flight particles collected in water allowed us to analyze the oxidation characteristics of bismuth. Micrometric powder shows the synthesis of snowman-like Bi/β-Bi₂O₃ Janus particles. The nanometric sized Bi₂O₃ powder was continuously obtained by spray oxidation, where its collection efficiency depends on processing parameters and showed spherical morphology and a highly pure tetragonal phase with narrow visible light absorbance (E_g = 2.26 eV). These optical characteristics indicate that the obtained β-Bi₂O₃ powder is suitable for high-performance visible-light photocatalyst.

通过火焰喷涂氧化法，由Bi-球团合成了具有不同半导体特性的光敏四方氧化铋粉末。本文报道了原料粒度和支座距离（SOD）对保持燃料/氧气比恒定的β- Bi ₂ O ₃物理性能的影响。从水中淬火的蒸发或飞行中颗粒中收集火焰喷雾氧化的粉末。火焰喷涂工艺参数的组合导致不同的β- Bi ₂ O ₃相含量，氧化特性，尺寸分布（纳米和微米级），形态和喷涂粉末的光学性能。最高的微米β使用Bi进料的12-60μm粒度分布，在30 cm的SOD下获得了在水中淬灭的-Bi ₂ O ₃含量。从水中收集的机载颗粒获得的粉末使我们能够分析铋的氧化特性。微米级粉末节目雪人状的Bi /合成β -Bi ₂ ö ₃的Janus颗粒。通过喷雾氧化连续获得纳米级的Bi ₂ O ₃粉末，其收集效率取决于工艺参数，并显示出球形形态和具有窄可见光吸收率的高纯四方相（E _g= 2.26 eV）。这些光学特性表明，所获得的β- Bi ₂ O ₃粉末适用于高性能可见光光催化剂。