Fabrication of a Heterobinuclear Redox Cycle to Enhance the Photocatalytic Activity of BiOCl

La3+ and Ni2+-doped BiOCl were prepared by sol-gel method and characterized by physicochemical and spectroscopic techniques. Their photocatalytic performances were investigated by the degradation of gentian violet under visible light. The results indicated that the co-doping of Ni and La significantly enhanced the photocatalytic performance of BiOCl. The photodegradation efficiency of LaNiBiOCl reached 95.5% in 105 min, which was 1.5 times that of BiOCl. This significant enhancement in photocatalytic activity was mainly attributed to the effective capture and transfer of photogenerated electrons between heterobinuclear La and Ni redox cycle, which benefited the photodegradation of active h(+) and the formation of active center dot O-2(-). Furthermore, the photodegradation activity did not show an obvious drop after five recycles, indicating that LaNiBiOCl was a promising semiconductor photocatalyst for the degradation of gentian violet.