Construction of bi-doped ZnO nanomaterials with boosted photocatalytic activity for the removal of contaminants- Shiyan Long,
- Bailin Xiang,
- Chongqing Yi,
- Yan Tian,
- Yuanyuan Hu,
- Canyu Zhong,
- Meichun Wu &
- Jinggao Wu
Abstract
The environmental pollution caused by organic dye wastewater presents a significant threat to human health. Photocatalysis has emerged as a promising approach for addressing wastewater contamination. In this study, a novel synthesis strategy was developed using the MOF-5 template method. By precisely regulating the amount of Bi3+ ions introduced into the MOF-5 precursor and employing controlled calcination, Bi-doped ZnO nanomaterials were successfully synthesized. XRD, SEM, TEM, and XPS analyses demonstrated that a 4% Bi doping level resulted in uniform incorporation of Bi into the ZnO crystal lattice, inducing local coordination modifications. EPR results indicated that the surface oxygen vacancy density of Bi每ZnO (4%) was higher than that of pure ZnO, which contributed to enhanced photocatalytic performance. UV degradation experiments revealed that at a Bi content of 4%, the degradation efficiency of methyl orange reached a maximum of 92%, significantly surpassing the 57.5% efficiency observed for pristine ZnO. Furthermore, cycling experiments confirmed the excellent stability of the catalyst. Reaction mechanism investigations indicated that photogenerated holes (h+) played a dominant role in the degradation of methyl orange by Bi每ZnO. Density functional theory (DFT) calculations indicate that bismuth doping renders the material metallic, thereby facilitating the efficient separation of photogenerated charge carriers. Under light irradiation, these doping-induced holes facilitated the formation of a space charge layer, thus facilitating the effective separation of photoinduced electron每hole pairs.
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Theoretical study of reaction of urea with methylamine: nucleophilic addition pathway
