Nano particles of a few α/β Bi₂O₃ hetero-junctions of various compositions synthesized by one- pot hydrothermal method, exhibit exceptional and synergistic photo-catalytic activity for the degradation of Rhodamine-B in aqueous solution under natural sunlight. Pure α and pure β Bi₂O₃ are also synthesized by control post heating of synthesized hetero-junction. The nano-materials were characterized by diffraction (XRD), microscopic and spectroscopic techniques. The XRD reveals α-β phase hetero-junctions of Bi₂O₃ are made of α-Bi₂O₃ and β-Bi₂O₃ with average dimensions within 13-113 and 5-71 nm respectively and having band gap range of 2.4 to 2.9 eV. The spectrophotometrically determined % degradation of the dye and associated rate constant on the best hetero-junction are increased by 4.5(/2.1) and 3.3(/1.2) times than these on pure α (/β). The effects of operational parameters and trapping agents have been analyzed. The maximum removal of the dye was achieved up to 99.6% in 3 hour using 0.5 g/L photo-catalyst at pH 3. The reusability test shows that the photo-catalytic activity is retained excellently due to change in chemical nature of the catalyst from α -Bi₂O₃ to β-Bi₂O_3, Bi₂O₂CO₃ and BiOCl. A suitable mechanism is proposed.

通过一锅水热法合成的各种组成的几个α/βBi ₂ O ₃异质结的纳米粒子，在自然阳光下，对水溶液中若丹明B的降解表现出优异的协同光催化活性。还通过控制合成异质结的后加热来合成纯α和纯βBi ₂ O ₃。通过衍射（XRD），显微技术和光谱技术对纳米材料进行了表征。所述XRD揭示的Biα-β相异质结₂ ö ₃是由α-Bi系₂ ö ₃和β-Bi系₂ ö ₃其平均尺寸分​​别在13-113和5-71 nm之间，并且带隙范围为2.4至2.9 eV。用分光光度法测定的染料降解百分数和最佳异质结上的相关速率常数比纯α（/β）分别提高了4.5（/2.1）和3.3（/1.2）倍。分析了操作参数和捕集剂的影响。使用0.5 g / L的pH为3的光催化剂，在3小时内染料的最大去除率达到了99.6％。可重复使用性测试表明，由于催化剂化学性质的改变，光催化活性得到了极好的保留。 α-Bi ₂ ö ₃至β-Bi系₂ ö _3，铋₂ ö ₂ CO ₃和BiOCl。提出了一种合适的机制。