CuxIr1-x Nanoalloy Catalysts Achieve Near 100% Selectivity for Aqueous Nitrite Reduction to NH3

Nitrite (NO2-) is an abundant contaminant in nature that threatens human health. A catalytic process that converts NO2- to less harmful products has been proven to be an effective strategy for NO2- removal. Most previous studies, however, targeted selectivity toward N-2 using Pd catalysts, which severely limits the potential for the recovery of value-added byproducts from the catalytic process. Here, we report experimental and theoretical evidence that both Ir and CuxIr(100-x) nanoparticles possess near 100% NH3 selectivity for NO2- reduction compared to the <1% NH3 selectivity achieved by nano-Pd. These NH3-selective catalysts could be useful for both water purification and ammonia production.