This work investigated the photodegradation of bromophenol blue (BPB) and indigo carmine (IC) dye under UV–Visible light using pure oxides of titanium and niobium, as well as TiO₂-Nb₂O₅ oxides containing 0.5, 2.5 and 5 wt% of TiO₂, prepared by wet impregnation of Nb₂O₅ with Ti tert-butoxide under inert atmosphere. The results of XRD and Raman spectroscopy showed the presence of anatase TiO₂ phase and T-Nb₂O₅ phase with orthorhombic structure in the pure TiO₂ and Nb₂O₅ oxides, respectively. The Nb₂O₅ oxides doped with TiO₂ presented a T-Nb₂O₅ phase, but there was no formation of TiNb₂O₇. TiO₂ anatase was observed in the mixed oxide with higher Ti content (5 wt% TiO₂). A zeta potential analysis showed positive surface charge values for titanium oxide and negative for niobium oxide and mixed oxides. The addition of up to 5 wt% of the TiO₂ fold the activity of Nb₂O₅ in the discoloration of both dyes. Pure TiO₂ exhibits higher initial activity, which could be related to its positive PZC and higher attraction to sulphonic groups present in the dyes. Despite of the lower initial rate, 2.5 and 5% TiNb catalysts achieved full degradation of the dyes after 4 h of reaction.

这项工作研究了使用纯钛和铌氧化物以及含0.5、2.5和5 wt％的TiO ₂ -Nb ₂ O ₅氧化物在紫外可见光下对溴酚蓝（BPB）和靛蓝胭脂红（IC）染料的光降解作用。通过在惰性气氛下用叔丁醇钛湿法浸渍Nb ₂ O ₅制备TiO ₂。XRD和拉曼光谱的结果表明在纯TiO ₂和Nb ₂ O ₅氧化物中分别存在具有正交晶结构的锐钛矿型TiO ₂相和T-Nb ₂ O ₅相。铌₂ O掺杂有TiO _2的5种氧化物呈现T-Nb ₂ O ₅相，但没有形成TiNb ₂ O ₇。在具有较高Ti含量（5wt％TiO ₂）的混合氧化物中观察到TiO ₂锐钛矿。ζ电位分析表明，氧化钛的表面电荷值为正，氧化铌和混合氧化物的电荷为负。在两种染料的变色中，最多添加5 wt％的TiO ₂会使Nb ₂ O ₅的活性倍增。纯TiO ₂具有较高的初始活性，这可能与其正的PZC和对染料中存在的磺酸基团的更高吸引力有关。尽管初始速率较低，但2.5和5％TiNb催化剂在反应4小时后仍能完全降解染料。