Department of Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States.
Department of Chemistry , University of Iowa , Iowa City , Iowa 52242 , United States.
Environ Sci Technol. 2018 Sep 4;52(17):10186-10195. doi: 10.1021/acs.est.8b02324. Epub 2018 Aug 17.
A commonly overlooked and largely unknown aspect of assessing the environmental and biological safety of engineered nanomaterials is their transformation in aqueous systems. Complex metal oxides are an important class of materials for catalysis, energy storage, and water purification. However, the potential impact of nano complex metal oxides on the environment upon improper disposal is not well understood. We present a comprehensive analysis of the interaction of an environmentally relevant oxyanion, phosphate, with a complex metal oxide nanomaterial, lithium cobalt oxide. Our results show that adsorption of phosphate to the surface of these materials drastically impacts their surface charge, rendering them more stable in aqueous systems. The adsorbed phosphate remains on the surface over significant periods of time, suggesting that desorption is not kinetically favored. The implications of this interaction may be increased dispersibility and bioavailability of these materials in environmental water systems.
评估工程纳米材料的环境和生物安全性时，通常会忽略一个很大的方面，即它们在水系统中的转化。复杂金属氧化物是催化、能量存储和水净化的一类重要材料。然而，对于纳米复合金属氧化物在不当处置时对环境的潜在影响，人们还不是很了解。我们对一种环境相关的含氧阴离子——磷酸盐与一种复合金属氧化物纳米材料（氧化锂钴）之间的相互作用进行了全面分析。研究结果表明，磷酸盐吸附到这些材料的表面会极大地影响它们的表面电荷，从而使它们在水系统中更加稳定。吸附的磷酸盐在很长一段时间内都留在表面上，这表明解吸在动力学上并不占优势。这种相互作用可能会增加这些材料在环境水系中的分散性和生物利用度。
