Interplay of Structural Properties and Redox Behavior in CeO2 Nanoparticles: Impact on Reactivity and Bioavailability

• DOI: 10.1021/acs.est.4c10490
• Publication Date: 2025-02-06T16:05:46Z
• Authors: Bei Liu; Yu Pan; Zixin Han; Yufei Shu; Xun Liu; Meng Zhang; Aling Wan; Mengxia Wang; Yixin Tan; Zhongying Wang
• Keywords: Reactivity

The environmental redox transformation of CeO2 is crucial for evaluating its ecological risk and understanding the geochemical cycling cerium (Ce). In this study, we examined effects crystallinity on dissolution monitored structural evolution during transformations. reductive reoxidation behavior (100 mg/L) was in presence 200 μM citrate. Our findings indicate that ligand-induced more pronounced with lower under both dark light conditions. This dependence related to intensive ligand complexation at oxygen vacancy sites, resulting a higher Ce(III) efficient photoelectron generation Ce(IV) reduction. During cyclic dissolution-reprecipitation, notably transformed into an amorphous phase, progressively decreasing nanoparticles. Consequently, fraction well-crystallized increased significantly from 1.2% first cycle 11.4% third cycle, suggesting transition structures interfacial reactivity. Similar observed oscillations soil environment. Additionally, hydroponic exposure experiments Arabidopsis thaliana, treated 100 mg/L 7 days, demonstrated Ce uptake by roots post-transformation, proportion CePO4 detected within plants. comprehensive study not only provides vital mechanistic insights processes but also aids assessing risks associated engineered nanomaterials.