Weak visible-light photo-piezoelectric synergistic catalyst based on the Bi2Fe4O9/Carbon-dots/g-C3N4 heterostructure

The photocatalytic efficiency towards water pollutant degradation has been limited due to the intermittence of the sunlight, low light utilization and rapid recombination of photoexcited electron-hole pairs. Here a photo-piezoelectric synergistic catalyst of Bi2Fe4O9/Carbon-dots/g-C3N4 heterostructure has been fabricated by loading Bi2Fe4O9 on the Carbon-dots modified g-C3N4 with opened g-C3N4 layer distance, which combined large surface area and photocatalytic activity of Carbon-dots/g-C3N4, and excellent piezoelectric effect of Bi2Fe4O9 for better electron-hole separation efficiency, achieved highly efficient antibiotics and dye degradation even under very weak visible-light treatment and mechanical stress. This heterostructure may fully use wave energy and light irradiation in numerous natural water environmental conditions and enhance the catalytic degradation efficiency, even in cloudy weather or at night when the photocatalytic activity is invalidated.