ABSTRACT
A micron-sized long-afterglow material, Sr2MgSi2O7:Eu,Ce, was utilized to conduct the hydrogen evolution reaction and oxygen evolution reaction, two half-reactions of water splitting, in the presence of sacrificial agents under both light and dark conditions for the first time. The as-synthesized Sr2MgSi2O7:Eu,Ce exhibited higher photocatalytic activity compared to that of the referenced Sr2MgSi2O7:Eu and Sr2MgSi2O7:Ce samples. Herein, in addition to benefiting from the long photogenerated carrier lifetime of long-afterglow materials, the higher photocatalytic activity was attributed to the conjugated electronic structure between Eu and Ce ions. This structure facilitates charge and energy transfer between them, leading to an enhanced photocatalytic efficiency. This research provides a new strategy for designing efficient long-afterglow material photocatalysts through the construction of conjugated electronic structures.
ABSTRACT
A heterostructure material g-C3N4/SrZrO3 was simply prepared by grinding and heating the mixture of SrZrO3 and g-C3N4. The morphology and structure of the synthesized photocatalysts were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM) and infrared spectra. It showed visible light absorption ability and much higher photocatalytic activity than that of pristine g-C3N4 or SrZrO3. Under the optimal reaction conditions, the hydrogen production efficiency is 1222 µmol·g-1·h-1 and 34 µmol·g-1·h-1 under ultraviolet light irradiation and visible light irradiation, respectively. It is attributed to the higher separation efficiency of photogenerated electrons and holes between the cooperation of g-C3N4 and SrZrO3, which is demonstrated by photocurrent measurements.