Nanostructured manganese oxides exhibit facet-dependent oxidation capabilities

摘要: Applying nanostructured manganese oxides (nano-MnOx) in contaminated agricultural lands offers the coupled benefits of oxidizing a range environmental contaminants while simultaneously releasing micronutrients (i.e., dissolved Mn2+) that are vital for crop growth. However, little is known about how key nanocrystal properties affect oxidation capabilities nano-MnOx. Here, we show an α-MnO2 nanostructure with predominantly exposed {100} facets (referred to as α-MnO2-100) exhibits greater capability bisphenol A (BPA, model pollutant commonly found lands) than {310} (α-MnO2-310), consistently amount Mn2+. Fitting reaction kinetics data using retarded rate shows α-MnO2-100 possesses more reactive sites higher reactivity. Density functional theory (DFT) calculations facet density binding and complexation BPA molecules on thermodynamically favorable, mainly due its specific surface topography. Moreover, ligand-promoted Mn(III) release experiments X-ray photoelectron spectroscopy analysis verify contains abundance Mn(III), effective electron acceptor Mn(IV). The findings suggest engineering can be exploited improve performance nano-MnOx sustainable applications.