Fig. 3.
Photocatalytic N2 reduction by the chalcogels. (A) The standard photocatalytic reaction of N2 reduction to NH4+. (B) Proton NMR (400 MHz) spectra showing the formation of NH4+ in a typical photocatalytic experiment as a function of reaction time. δ, chemical shift. (C) Photocatalytic N2 reduction performance comparisons for FeMoS–SnS, FeMoS–FeS–SnS and FeS–SnS chalcogels. C(NH4+): concentration of NH4+. ppm can be expressed as milligrams per liter. One ppm equals the 1 mg of NH4+ in 1 L of H2O.