In recent years, due to the advancement in nanotechnology, advanced oxidation processes (AOPs), especially sonocatalysis and photocatalysis, have become a topic of interest for the elimination of pollutants from contaminated water. In the research work reported here, an attempt has been made to study and establish a physicochemical mechanism for the catalytic activity of copper oxide nanoparticles (CuO NPs) in AOPs using the degradation of dyes as model contaminants. CuO NPs exhibited brilliant sonocatalytic and photocatalytic activities for the degradation of a cationic dye (Victoria Blue) as well as an anionic dye (Direct Red 81). The degradation efficiency of CuO NPs was calculated by analysing the variation in the absorbance of dye under a UV-Vis spectrophotometer. The influence of different operating parameters on the catalytic activity of CuO NPs, such as the amount of catalysts dose, pH of the solution, and the initial dye concentration, was thoroughly investigated. In addition, the kinetic process for the degradation was also examined. It was observed that both dyes exhibited and followed the pseudo-first-order kinetics relation. The rate constant for sonocatalysis was high as compared to photocatalysis. The rate constant for both sonocatalysis and photocatalysis was successfully established, and reusability tests were done to ensure the stability of the used catalysts. To get an insight into the degradation mechanism, experiments were performed by using ^⋅OH radical scavengers. The efficacy of CuO NPs for dye decolorization was found to be superior for the sonocatalyst than the photocatalyst.

中文翻译：

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CuO纳米粒子对光催化降解声纳的研究

近年来，由于纳米技术的进步，先进的氧化过程（AOP），尤其是声催化和光催化，已成为消除受污染水中污染物的重要话题。在这里报道的研究工作中，已经尝试研究和建立一种以染料的降解为模型污染物的氧化铜纳米颗粒（CuO NPs）在AOP中的催化活性的物理化学机制。CuO NP对阳离子染料（维多利亚蓝）和阴离子染料（直接红81）的降解表现出出色的声催化和光催化活性。通过在紫外可见分光光度计下分析染料的吸光度变化来计算CuO NPs的降解效率。彻底研究了不同操作参数对CuO NPs催化活性的影响，例如催化剂用量，溶液的pH值和初始染料浓度。另外，还研究了降解的动力学过程。观察到两种染料均表现出并遵循伪一级动力学关系。与光催化相比，声催化的速率常数较高。成功建立了声催化和光催化的速率常数，并进行了可重复使用性测试以确保所用催化剂的稳定性。为了深入了解降解机理，通过使用 还研究了降解的动力学过程。观察到两种染料均表现出并遵循伪一级动力学关系。与光催化相比，声催化的速率常数较高。成功建立了声催化和光催化的速率常数，并进行了可重复使用性测试以确保所用催化剂的稳定性。为了深入了解降解机理，通过使用 还研究了降解的动力学过程。观察到两种染料均表现出并遵循伪一级动力学关系。与光催化相比，声催化的速率常数较高。成功建立了声催化和光催化的速率常数，并进行了可重复使用性测试以确保所用催化剂的稳定性。为了深入了解降解机理，通过使用 进行了可重复使用性测试，以确保所用催化剂的稳定性。为了深入了解降解机理，通过使用 进行了可重复使用性测试，以确保所用催化剂的稳定性。为了深入了解降解机理，通过使用^· OH自由基清除剂。发现CuO NPs对染料脱色的功效对于声催化剂比对光催化剂更好。