Surface coating effects on the sorption and dissolution of ZnO nanoparticles in soil
- 10 July 2019
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Environmental Science: Nano
- Vol. 6 (8), 2495-2507
- https://doi.org/10.1039/c9en00348g
Abstract
Soil pH and dissolved organic matter (DOM) content are among the most important factors affecting the bioavailability of Zn and the binding and dissolution of ZnO nanoparticles (NPs). To investigate the effect of NP surface chemistry and DOM on the behavior of ZnO NPs and ZnSO4 in soil solution at pH 6 and 8, we synthesized electrostatically stabilized (bare positively charged ZnO, and negatively charged (ZnO–Zn3(PO4)2 core–shell NPs)), and sterically and electrosterically stabilized (neutral dextran (DEX), and negatively charged dextran sulfate (DEX(SO4))–ZnO NPs), respectively. We hypothesized that negatively charged ZnO NPs will have higher total Zn concentrations as opposed to neutral and positively charged ones in soil pore water at higher pH, with higher dissolution of the NPs at lower pH. At pH 8, core–shell and DEX–ZnO NP amendments had significantly higher total Zn concentration than ZnSO4. To investigate the unexpected behavior of the neutral DEX–ZnO NPs, we performed sorption isotherm experiments which showed that DEX–ZnO NPs had the highest affinity for DOM of all ZnO NPs, which likely enhanced their colloidal stability and partitioning in soil pore water, especially at pH 8. In simple aqueous solution, with increasing ionic strength, negatively charged core–shell and DEX(SO4) ZnO NPs were the most stable against aggregation. When DOM was introduced in to the system, the as-synthesized surface chemistry of the particles was altered, and all NPs became negatively charged. Dissolved Zn concentrations in soil extracts of NP amendments were similar while ZnSO4 amended soils had the highest dissolved Zn among all treatments.Keywords
Funding Information
- National Science Foundation (CBET- 1530594)
- National Institute of Food and Agriculture (1010358)
This publication has 47 references indexed in Scilit:
- The effect of pH on the toxicity of zinc oxide nanoparticles to Folsomia candida in amended field soilEnvironmental Toxicology and Chemistry, 2013
- Agglomeration and dissolution of zinc oxide nanoparticles: role of pH, ionic strength and fulvic acidEnvironmental Chemistry, 2013
- EFFECT OF NANOSCALE ZINC OXIDE PARTICLES ON THE GERMINATION, GROWTH AND YIELD OF PEANUTJournal of Plant Nutrition, 2012
- Biotic and Abiotic Interactions in Aquatic Microcosms Determine Fate and Toxicity of Ag Nanoparticles. Part 1. Aggregation and DissolutionEnvironmental Science & Technology, 2012
- Environmental Transformations of Silver Nanoparticles: Impact on Stability and ToxicityEnvironmental Science & Technology, 2012
- Polymeric Coatings on Silver Nanoparticles Hinder Autoaggregation but Enhance Attachment to Uncoated SurfacesLangmuir, 2012
- Sulfidation Processes of PVP-Coated Silver Nanoparticles in Aqueous Solution: Impact on Dissolution RateEnvironmental Science & Technology, 2011
- Aggregation and Dissolution of 4 nm ZnO Nanoparticles in Aqueous Environments: Influence of pH, Ionic Strength, Size, and Adsorption of Humic AcidLangmuir, 2011
- Soil factors associated with zinc deficiency in crops and humansEnvironmental Geochemistry and Health, 2009
- Adsorption and desorption of metals on ferrihydrite: reversibility of the reaction and sorption properties of the regenerated solidEnvironmental Science & Technology, 1987