Proceedings of Materials for Sustainable Development Conference (MAT-SUS) (NFM22)
DOI: https://doi.org/10.29363/nanoge.nfm.2022.116
Publication date: 11th July 2022
Nitrate (NO2-) is the world’s most widespread surface and ground water contaminant that causes adverse effects on human health such as methemoglobinemia (“blue baby syndrome”) and cancer. Most abiotic nitrate removal strategies center on the use of ion exchange resins. Ion exchange resins are effective, yet are not sustainable the process generates a large amount of waste. Biological approaches are inapplicable for removal of high nitrate ions and large scale applications as well as possibility of bacterial contamination in the drinking water. Electrocatalytic NO3- remediation; however, is one emerging approach for nitrate removal which does not produce waste as NO3- is converted directly to inert dinitrogen (N2) gas. The main challenge with electrocatalytic NO3- reduction is the low NO3- conversion yield, poor N2 selectivity, and lack of understanding regarding catalyst stability. The production of equally harmful contaminant intermediate species such as nitrite (NO2-) and ammonium (NH4+), has also limited the applicability of electrochemical routes for nitrate remediation. Electrocatalytic NO3- valorization is another emerging approach for nitrate removal. Here, NO3- is converted directly to ammonium (NH4+). The main challenge with valorization of NO3- is the low activity and selectivity of the NO3- to NH4+ and the structure sensitivity studies are insufficient. Here, we will describe an investigation on the electrocatalytic properties of palladium (Pd) and copper (Cu) which contains structured surfaces and coatings. The primary aim is to identify which facets and surfaces are highly active and selective for nitrate and nitrite reduction. Engineering the structure of Pd and Cu that enhances the NO3- removal efficiency and enables to steer the selectivity toward N2 and NH4+. To achieve the real-life applications, we also verify the long-term operations for the developed electrocatalysts.Nitrate (NO2-) is the world’s most widespread surface and ground water contaminant that causes adverse effects on human health such as methemoglobinemia (“blue baby syndrome”) and cancer. Most abiotic nitrate removal strategies center on the use of ion exchange resins. Ion exchange resins are effective, yet are not sustainable the process generates a large amount of waste. Biological approaches are inapplicable for removal of high nitrate ions and large scale applications as well as possibility of bacterial contamination in the drinking water. Electrocatalytic NO3- remediation; however, is one emerging approach for nitrate removal which does not produce waste as NO3- is converted directly to inert dinitrogen (N2) gas. The main challenge with electrocatalytic NO3- reduction is the low NO3- conversion yield, poor N2 selectivity, and lack of understanding regarding catalyst stability. The production of equally harmful contaminant intermediate species such as nitrite (NO2-) and ammonium (NH4+), has also limited the applicability of electrochemical routes for nitrate remediation. Electrocatalytic NO3- valorization is another emerging approach for nitrate removal. Here, NO3- is converted directly to ammonium (NH4+). The main challenge with valorization of NO3- is the low activity and selectivity of the NO3- to NH4+ and the structure sensitivity studies are insufficient. Here, we will describe an investigation on the electrocatalytic properties of palladium (Pd) and copper (Cu) which contains structured surfaces and coatings. The primary aim is to identify which facets and surfaces are highly active and selective for nitrate and nitrite reduction. Engineering the structure of Pd and Cu that enhances the NO3- removal efficiency and enables to steer the selectivity toward N2 and NH4+. To achieve the real-life applications, we also verify the long-term operations for the developed electrocatalysts.
This material is based upon the work supported by the National Science Foundation under Grant nos 1846611 and 1933646.