Effect of dissolved organic matter on the stability of magnetite   nanoparticles under different pH and ionic strength conditions

doi:10.1016/j.scitotenv.2010.03.033

CORC > 北京大学 > 城市与环境学院

	Effect of dissolved organic matter on the stability of magnetite nanoparticles under different pH and ionic strength conditions
	Hu, Jun-Dong ; Zevi, Yuniati ; Kou, Xiao-Ming ; Xiao, John ; Wang, Xue-Jun ; Jin, Yan
刊名	science of the total environment
	2010
关键词	Engineered nanoparticle Magnetite Aggregation Stability kinetics Humic acid DLVO theory AFM DYNAMIC LIGHT-SCATTERING AGGREGATION RATE CONSTANTS IRON-OXIDE PARTICLES HUMIC-ACID MINERAL PARTICLES COLLOID STABILITY HEMATITE NANOPARTICLES RHEOLOGICAL PROPERTIES INTERPARTICLE FORCES ADSORPTION
DOI	10.1016/j.scitotenv.2010.03.033
英文摘要	Upon release of engineered nanoparticles (NPs) into the subsurface environment, their fate and transport and hence their potential environmental and public health impacts will largely depend on how stable these NPs are as suspended particles in the natural environment. In this study, we systematically examine the effect of humic acid (HA) on surface charge status and aggregation potential of magnetite (Fe(3)O(4)) NPs, selected as a model for metal oxide NPs, over a wide range of solution pH and ionic strength. Through zeta potential (ZP) measurements, we found that HA can adsorb to magnetite particles hence modifying their surface charge status. At low loadings, the presence of HA can induce a shift in the point zero of charge of due to partial neutralization of the positive charges on magnetite NPs. At high loadings, however. HA is capable of completely cover magnetite particles giving rise to a suspension ZP profile similar to its own (observed in presence of 20 mg L(-1) HA). These impacts on surface charge correspond well with the observed aggregation behaviors in the absence and presence of HA. From the dynamic light scattering (DLS) measurements, fast aggregation, which is independent of solution chemistry, took place when the pH is close to the point zero charge (PZC) and the ionic strength is above the critical coagulation concentration (CCC). At high ionic strength, a small dose (2 mg L(-1)) of HA stabilized the NPs' suspension significantly. This stabilization effect is substantially enhanced with increasing HA concentration. The calculated DLVO (Derjaguin-Landau-Verwey-Overbeek) interaction energy profiles, using experimentally determined values of Hamaker constant, adequately support the experimental observations. The DLVO analysis further reveals the possible presence of secondary energy minima and the possibility of deaggregation of magnetite agglomerates. The complexation of HA-NPs and the HA effects on NPs aggregations were confirmed by atomic force microscope (AFM) observations. (C) 2010 Elsevier B.V. All rights reserved.; Environmental Sciences; SCI(E); PubMed; 39; ARTICLE; 16; 3477-3489; 408
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/160701]
专题	城市与环境学院
推荐引用方式 GB/T 7714	Hu, Jun-Dong,Zevi, Yuniati,Kou, Xiao-Ming,et al. Effect of dissolved organic matter on the stability of magnetite nanoparticles under different pH and ionic strength conditions[J]. science of the total environment,2010.
APA	Hu, Jun-Dong,Zevi, Yuniati,Kou, Xiao-Ming,Xiao, John,Wang, Xue-Jun,&Jin, Yan.(2010).Effect of dissolved organic matter on the stability of magnetite nanoparticles under different pH and ionic strength conditions.science of the total environment.
MLA	Hu, Jun-Dong,et al."Effect of dissolved organic matter on the stability of magnetite nanoparticles under different pH and ionic strength conditions".science of the total environment (2010).