本研究以固相合成法製備高熵氧化物(Bi0.2La0.2Nd0.2Sm0.2 Eu0.2)(Fe0.875Mn0.125)O3(BLNSEFMO)、尖晶石鐵氧體Mn0.4Zn0.6 Fe2O4 (MZFO)以及兩者混合之複合材料0.6BLMSEFMO-0.4 MZFO。藉由X射線繞射 (XRD) 分析，BLNSEFMO、MZFO及其複合材料均為純相結構。後續對XRD 數據進行TOPAS 擬合，結果顯示兩相的比例近似於原始劑量比。複合材料於1100 °C表現出較佳的結晶度，其晶粒尺寸為 1.61 μm。此外，在Tauc 曲線中解析的兩個斜率，分別對應BLNSEFMO與MZFO的能隙，進一步證實該樣品為兩相複合物。
接著以0.6BLNSEFMO-0.4MZFO作為催化劑測量對甲基藍(MB)的降解效率，在超聲波震盪60分鐘後，降解效率為95%，其反應速率常數為0.0507 min⁻¹。相較之下，未添加催化劑的對照組降解效率僅有16%，證實其優異的降解效率源於0.6BLNSEF MO-0.4MZFO複合材料的催化作用。後續透過鈦鹽比色法證實，在超聲波震盪下水溶液會產生H2O2。同時，透過X射線光電子能譜(XPS)分析，在降解反應後複合材料中的Fe2+離子比例由46%提升至67%且樣品表面的吸附氧含量有所增加。綜上所述，此催化機制由超聲-類芬頓(Sono/Fenton-Like)反應作用所致。

In this study, high entropy oxide (Bi0.2La0.2Nd0.2Sm0.2Eu0.2)(Fe0.875 Mn0.125)O3 (BLNSEFMO) and Mn-Zn spinel ferrite Mn0.4Zn0.6Fe2O4 (MZFO) were synthesized by solid-state reaction. BLNSEFMO and MZFO were then mixed according to the weight ratio of 60/40 and sintered at 900-1100 °C to form a composite. X-ray diffraction (XRD) confirmed that both BLNSEFMO and MZFO had a pure phase. TOPAS fitting of XRD data showed that the ratio of the two phases was 63/37, approximately equal to the nominal composition of the starting powder mixture. The composites sintered at 1100 °C exhibited better crystallinity with a grain size of 1.61 μm. Two slopes in the Tauc plot was resolved, corresponding to the band absorptions of BLNSEFMO and MZFO, which confirmed the samples were a mixture of two phases. The degradation performance of methylene blue (MB) was evaluated using 0.6BLNSEFMO-0.4MZFO as the catalyst under the irradiation of 200 W ultrasonic wave. A very rapid MB degradation rate was observed, which gave rise to a 95% reduction in MB concentration after 60 minutes under ultrasonic vibration. The pseudo-first order reaction rate was calculated to be 0.0508 min⁻¹. To confirm that such a fast degradation was indeed due to the catalytic action of the 0.6BLNSEFMO-0.4MZFO composites, the MB degradation was carried out without the composites and a much lower degradation efficiency of 16% was obtained. The catalytic mechanism for the rapid MB degradation was attributed to a sono-Fenton-like process. The existence of H2O2 in the water under ultrasonic vibration was confirmed by titanium sulfate method, while X-ray photoelectron spectroscopy (XPS) revealed that the Fe2+ ions in the composites varied from 46% to 67% before and after the degradation reaction. XPS also showed an increased in the adsorbed oxygen after the reaction. So, the catalytic process was correlated to both the ultrasonic and Fenton-like actions.

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