羅丹明B是工業廢水中常見的染料污染物。我們研究並評估了BaTiO3-Ag2O-Ag在模擬太陽光照射下光降解羅丹明B的適用性。為了提高其性能，首先獲得了BTO-Ag2O的最佳比例，然後加入還原劑（H2O2）來探索Ag奈米粒子在其中的作用。為了比較和評估單一材料和複合材料之間晶體結構和形態的變化，進行了 XRD（X光繞射）、SEM（掃描式電子顯微鏡）、TEM（穿透式電子顯微鏡）和BET（Brunauer-Emmett-Teller）量測。元素分佈和價態分析透過 EDS偵測和XPS（X光光電子能譜）分析已知。此外，此研究闡述了BTO-Ag2O-Ag對羅丹明B的降解途徑和去除機制。在壓電光催化下，(1-x-y)BTO-xAg2O-yAg (x = 59.7 and y = 2.2 mol %) 擁有最高的羅丹明B降解率，在30分鐘內分解超過70%羅丹明B。結果顯示，具有壓電性的異質結構複合材料在廢水處理領域可以作為一種適合的光催化劑。

Rhodamine B (RhB) is a dye pollutant commonly present in wastewater from industry. BaTiO3-Ag2O-Ag for the photodegradation of RhB under irradiation was investigate and evaluated. To enhance its performance, an optimal ratio of BTO-Ag2O was obtained first, and then a reducing agent (H2O2) was further added to explore a role of Ag nanoparticles in the composite. To compare and evaluate changes in their crystalline structures and morphologies between single constitutive material and composites, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Brunauer-Emmett-Teller measurements were conducted. The distribution of elements and valence states were determined through energy-dispersive X-ray spectroscopy mapping and X-ray photoelectron spectroscopy analyses, respectively. Furthermore, the degradation pathways and removal mechanisms of the RhB by the BTO-Ag2O-Ag were elaborated. The composite, (1-x-y)BTO-xAg2O-yAg (x = 59.7 and y = 2.2 mol %) , had the highest RhB degradation rate, which decomposed more than 70% RhB within 30 min and over 90% decomposition after an hour for sonophotocatalysis. Our results indicate that the piezoelectric heterostructure composites are a promising photocatalyst in the wastewater treatment field.

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