Due to the antibacterial characteristics, numerous-growing applications of silver nanoparticles (AgNPs) and its coated forms impact water treatment by ozone. The influence of ozone on the aggregation of bare AgNPs and polyvinylpyrrolidone-capped form (PVP-AgNPs) was investigated, as toxicity of NPs depends on particle aggregation/surface charge. Full factorial experimental design was employed to investigate the impact of pH, concentration of NPs’ suspension, and ozonation time on bare and PVP-capped AgNPs. Z-Average, zeta potential, and polydispersity index (PdI) of NPs were measured as aggregation criteria. The most effective variables on aggregation of NPs were the coating layer (40–75.5% contribution), pH (14.1–29.6% contribution), and ozonation time (6.5–10.1% contribution), respectively. The aggregation rate increased with increasing ozonation time and decreased with pH. The aggregation of ozonated AgNPs (Z-average up to ~ 4000 nm) was much greater than that of ozonated PVP-AgNPs (Z-average up to ~ 450 nm) due to interaction of ozone–PVP stabilizing layer. During ozonation, the PVP-AgNPs’ surface charge shifted from − 6.62 (steric repulsion) to − 29.17 mV (electrosteric repulsion) at pH 7.5, thereby requiring more treatment time to aggregate compared with AgNPs.

由于抗菌特性，银纳米颗粒（AgNPs）及其涂层形式的大量应用影响了臭氧对水的处理。研究了臭氧对裸露的AgNPs和聚乙烯吡咯烷酮封端形式（PVP-AgNPs）聚集的影响，因为NPs的毒性取决于颗粒的聚集/表面电荷。采用全因子实验设计来研究pH值，NPs悬浮液的浓度以及臭氧化时间对裸露的和PVP封端的AgNPs的影响。测量NP的Z平均，ζ电位和多分散指数（PdI）作为聚集标准。对NP聚集最有效的变量分别是涂层（贡献率40-75.5％），pH（贡献率14.1-29.6％）和臭氧化时间（贡献率6.5-10.1％）。聚集速率随臭氧化时间的增加而增加，随pH的降低而减小。由于臭氧-PVP稳定层的相互作用，臭氧化的AgNPs的聚集（Z均值约为4000纳米）比臭氧化的PVP-AgNPs的聚集（Z均值约为450 nm）要大得多。在臭氧化期间，PVP-AgNPs的表面电荷在pH 7.5时从− 6.62（空间排斥）转变为− 29.17 mV（电子空间排斥），因此与AgNPs相比，需要更多的处理时间才能聚集。