Near-infrared driven photocatalyst (Ag/BiO2-x) with post-illumination catalytic memory

Photocatalysts driven by solar energy have attracted interest in environmental applications. However, there are some drawbacks that obstruct their effectiveness in solar radiation; for example, the representative photocatalyst, TiO 2 , can only work in UV light, and they require continuous light irradiation to form electron-hole pairs. As a result, investigating their responsiveness to visible and near-infrared (NIR) light and maintaining catalytic efficiency in the dark condition has been the main research goal with respect to next generation photocatalysts. To achieve this, in this work, we synthesized an Ag/BiO 2-x composite using a hydrothermal and dark-deposition method, and demonstrated their photocatalytic performance of as-made NIR photocatalyst via photodegradation of rhodamine B in the dark and NIR irradiation condition. The synthesized photocatalyst sample exhibited decent catalytic activity under NIR light irradiation and maintained catalytic activity for a long time period even after the light was eliminated. This study provides a new strategy to achieve continuous removal of pollutants during daylight and night. • NIR-driven photocatalyst (Ag/BiO2-x) was prepared by hydrothermal and dark-deposition method. • Photocatalytic degradation of rhodamine B was tested in NIR irradiation and dark condition. • Catalytic activity was maintained for a long time even after the light was eliminated. • Post-illumination photocatalytic memory effect was revealed in Ag/BiO 2-x samples.