Zero-Valent Iron Nanocatalysts via Polymers or Metal Hydroxide Passivation: Implications for Advanced Oxidation Processes
Year: 2025
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Zero-valent iron (ZVI) nanocatalysts are promising materials for environmental remediation (e.g., wastewater treatment) via advanced oxidation processes (AOPs) due to their ability to generate reactive oxygen species (ROS). However, their high reactivity often leads to rapid surface oxidation and a limited stability. This study evaluates the effect of different surface coatings on the stability and ROS production of ZVI nanocatalysts. The coatings tested include organic molecules such as mannitol and polyvinylpyrrolidone (PVP), as well as combinations with thin layers of metal hydroxides (M(OH) 2, where M = Ni or Mn). Hydroxyl radical ( • OH) generation was quantified using electron paramagnetic resonance (EPR) spectroscopy over a period of 0 to 7 days in acetate buffer (pH 5). Results show that incomplete PVP coverage leads to a 90% decrease in ROS production within 24 h, while full coverage preserves catalytic activity for at least 1 day. Among inorganic coatings, Mn(OH) 2 maintained stable ROS generation for 7 days, whereas Ni(OH) 2 showed significant degradation after 24 h. These findings highlight the importance of coating selection and surface passivation to enhance ZVI stability and extend its catalytic performance in AOP applications, providing design guidelines for nanocatalysts in Fenton-like processes for water purification and environmental remediation.
Source: ACS Applied Nano Materials
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Awards: G1175115578, G2198898644, G2262748287, G2656258963, G2933350706, G294895050, G300979063, G3345895242, G3477743816, G3480869486, G4036219695, G425668148, G5080475149, G5338730000, Exploring wooden materials in hybrid printed electronics: a holistic approach towards functional electronics with net zero carbon emissions, G7084143925, G7169023097, G7313509320, G7340230215, Nanomaterials for Enzymatic Control of Oxidative Stress Toxicity and Free Radical Generation, G786536119
OpenAlex ID: W4416820809