This study reports the production of a heterojunction copper oxide-zinc oxide nano-photocatalyst based on lemon leaf extract, which acted as both a stabilizer and a capping and reducing agent. The fabricated photocatalyst had a smooth surface with numerous functional groups, and its energy band gap was measured to be 3.14 eV, which is suitable for photocatalytic applications. Toxic Congo Red dye was used as a model pollutant to investigate the photocatalytic degradation performance of the proposed CuO-ZnO nano-photocatalyst. The photocatalyst exhibited a rapid degradation rate under sunlight irradiation, reducing the concentration of the dye by almost 70 % within 50 min and exhibited pseudo-first-order kinetics. The performance of the photocatalyst was also evaluated based on its quantum yield and figure of merit, which were found to be 6.63 x 10 molecules photonand 3.31 x 10, respectively. In addition, the proposed catalyst displayed good stability for up to 5 cycles. Based on these results, the fabricated CuO-ZnO nano-photocatalyst outperformed previously reported photocatalysts. The mechanisms associated with the dye degradation were also explained by an interfacial charge transfer reaction.

中文翻译：

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用于染料降解的铜锌耦合异质结光催化剂：基于量子产率和品质因数的性能评估

这项研究报道了基于柠檬叶提取物的异质结氧化铜-氧化锌纳米光催化剂的生产，该催化剂既充当稳定剂又充当封端剂和还原剂。所制备的光催化剂具有光滑的表面和众多的官能团，其能带隙测量为3.14 eV，适合光催化应用。使用有毒刚果红染料作为模型污染物来研究所提出的 CuO-ZnO 纳米光催化剂的光催化降解性能。该光催化剂在阳光照射下表现出快速的降解速率，在50分钟内将染料的浓度降低了近70%，并表现出准一级动力学。光催化剂的性能还根据其量子产率和品质因数进行了评估，结果分别为 6.63 x 10 分子光子和 3.31 x 10 分子。此外，所提出的催化剂在长达 5 个循环中表现出良好的稳定性。基于这些结果，制备的 CuO-ZnO 纳米光催化剂优于之前报道的光催化剂。与染料降解相关的机制也可以通过界面电荷转移反应来解释。