Plasmon Sensitized Heterojunction 2D Ultrathin Ag/AgI-δ-Bi2O3 for Enhanced Photocatalytic Nitrogen Fixation

A novel 2D ultrathin Ag/AgI-δ-Bi2O3 photocatalyst was constructed by a facile hydrothermal and in situ photodeposition method, which presented a uniform nanosheet structure with an average height of 6 nm. Its composition, morphology and light-harvesting properties were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis spectrophotometer (UV–vis) and photoluminescence (PL) measurements in detail. The Ag/AgI-δ-Bi2O3 nanocomposites showed an excellent photocatalytic nitrogen fixation performance of 420 μmol L−1 g−1 h−1 in water without any sacrificial agent. The introduction of Ag/AgI nanoparticles caused the morphology modification of δ-Bi2O3, a higher concentration of oxygen vacancy, and the construction of a plasmon sensitized heterojunction, resulting in enhanced light absorption, improved separation efficiency of charge carriers and strong N2 absorption and activation ability, which are responsible for the superior photocatalytic performance of Ag/AgI-δ-Bi2O3.