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NaTaO_(3-x)N_x catalysts were synthesized by a hydrothermal(H) and a solid-state(S) methods in this study.The H-and S-NaTaO_(3-x)N_x samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), UV–visible(UV–vis) diffuse reflectance spectroscopy, and photoluminescence(PL) spectroscopy. The XRD patterns of the H-and S-samples showed peaks indexed to the pure phase of perovskite NaTaO_3 and minor peaks assignable to Ta_3N_5 at various synthesis temperatures. Substitution of oxygen by nitrogen ions causes the light absorption of the H-and S-NaTaO_(3-x)N_x samples to be extended to the 600–650 nm region, thus making the samples visible-light active. The NaTaO_(3-x)N_x samples exhibited photocatalytic activity for H_2 and O_2 evolution from aqueous methanol and silver nitrate solutions under visible-light irradiation. The UV–vis and PL spectra of the Hand S-catalysts revealed the presence of cationic vacancies and reduced metallic species, which acted as recombination centers. These results demonstrated that the preparation method plays a critical role in the formation of defect states, thereby governing the photocatalytic activity of the NaTaO_(3-x)N_x catalysts.
NaTaO 3-x N x catalysts were synthesized by a hydrothermal (H) and a solid-state (S) methods in this study.The H-and S-NaTaO 3-x N x samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible (UV-vis) diffuse reflectance spectroscopy, and photoluminescence (PL) spectroscopy. The XRD patterns of the H- and S- indexed to the pure phase of perovskite NaTaO_3 and minor peaks assignable to Ta_3N_5 at various synthesis temperatures. Substitution of oxygen by nitrogen ions causes the light absorption of the H-and S-NaTaO_ (3-x) N_x samples to be extended to the 600 The NaTaO_ (3-x) N_x samples exhibited photocatalytic activity for H_2 and O_2 evolution from aqueous methanol and silver nitrate solutions under visible-light irradiation. The UV-vis and PL spectra of the Hand S-catalysts revealed the presence of cationic vacancies and re ductile metallic species, which acted as a recombination centers, thereby acted as a recombination centers.