Silver nanoparticles (AgNPs) are among the most applied nanomaterials and have great potential to be present in the environment. Dissolved black carbon (DBC) is ubiquitous in soil as a result of large-scale application of biomass-derived black carbon as soil amendments, while its impacts on the transport of AgNPs remain unclear. In this study, two DBCs with different functional groups were prepared at 300 and 500 °C (DBC300 and DBC500), and their impacts on the transport of uncoated AgNPs (Bare-AgNP) and polyvinylpyrrolidone-coated AgNPs (PVP–AgNP) in saturated quartz sand were investigated. The transport of PVP-AgNP was much higher than Bare-AgNP under the same conditions because of the increased steric hindrance provided by PVP surface coating. The transport of two kinds of AgNPs was both enhanced by the DBCs under all the experimental conditions. DBC500 displayed a stronger enhancement effect than DBC300 on PVP-AgNP transport, but DBC300 facilitated the migration of Bare-AgNP more significantly than DBC500. The higher aromaticity and stronger hydrophobicity of DBC500 drove it to be adsorbed on the surface of PVP-AgNP, thus providing stronger steric hindrance and promotion effect on PVP-AgNP transport. However, DBC300 contained surface sulfhydryl groups, which bound with the Bare-AgNP tightly, therefore it greatly promoted Bare-AgNP transport via enhanced steric hindrance. (X)DLVO calculations indicated DBCs generally increased the energy barrier between the AgNPs and sand grains. The results shed light on the vital roles of both the properties of AgNPs and DBCs on the fate and environmental behaviors of silver nanomaterials in complex environments.

银纳米粒子 (AgNPs) 是应用最广泛的纳米材料之一，在环境中具有巨大的潜力。由于生物质衍生黑碳作为土壤改良剂的大规模应用，溶解黑碳 (DBC) 在土壤中无处不在，但其对 AgNPs 运输的影响尚不清楚。在本研究中，在 300 和 500 °C 下制备了两种具有不同官能团的 DBC（DBC300 和 DBC500），及其对未包覆的 AgNPs（Bare-AgNP）和聚乙烯吡咯烷酮包覆的 AgNPs（PVP-AgNP）在饱和溶液中传输的影响。石英砂进行了研究。由于 PVP 表面涂层提供的空间位阻增加，在相同条件下 PVP-AgNP 的传输远高于 Bare-AgNP。在所有实验条件下，DBCs 都增强了两种 AgNPs 的传输。DBC500 对 PVP-AgNP 迁移显示出比 DBC300 更强的增强作用，但 DBC300 比 DBC500 更显着促进 Bare-AgNP 的迁移。DBC500 较高的芳香性和较强的疏水性促使其吸附在 PVP-AgNP 表面，从而对 PVP-AgNP 传输提供更强的位阻和促进作用。然而，DBC300 含有表面巯基，与 Bare-AgNP 紧密结合，因此它通过增强的空间位阻极大地促进了 Bare-AgNP 的传输。(X)DLVO 计算表明 DBC 通常会增加 AgNPs 和砂粒之间的能量势垒。