Nano-SCHeMe: Nanomaterial Sponge Coatings for Heavy Metals, an Environmental Remediation Platform

The presence of heavy metals in our water supply poses an immense global public health burden. Heavy metal consumption is tied to increased mortality and a wide range of insidious health outcomes. In recent years, great strides have been made toward nanotechnological approaches for environmental problems, specifically the design of adsorbents to detoxify water, as well as for a related challenge of recovering valuable metals at low concentrations. However, applying nanomaterials at scale and differentiating which nanomaterials are best suited for particular applications can be challenging. Here, we report a methodology for loading nanomaterial coatings onto adsorbent membranes, testing different coatings against one another, and leveraging these materials under a variety of conditions. Our tailored coating for lead remediation, made from manganese-doped goethite nanoparticles, can filter lead from contaminated water to below detectable levels when coated onto a cellulose membrane, and the coated membrane can be recovered and reused for multiple cycles through mild tuning of pH. The Nano-SCHeMe methodology demonstrates a platform approach for effectively deploying nanomaterials for environmental applications and for direct and fair comparisons among these nanomaterials. Moreover, this approach is flexible and expansive in that our coatings have the potential to be applied to a range of sorbents.