Highly efficient Bi/BiOCl with oxygen vacancies photocatalyst with synergetic effects of oxygen vacancy, surface plasmon resonance, and electron sink effects of metallic Bi

Bi/BiOCl with oxygen vacancies composite was synthesized through a facile and rapid in situ surface reduction of BiOCl, utilizing NaBH 4 as the reductant. The reduction process yielded metallic Bi nanoparticles on the surface of BiOCl and meanwhile created the oxygen vacancies within the BiOCl lattice. As a consequence, the as‐synthesized Bi/BiOCl composites exhibited a substantially enhanced visible‐light absorption capacity, whereas pure BiOCl was only responsive to ultraviolet light. Additionally, the Bi/BiOCl composite demonstrated a markedly accelerated photodegradation rate of Rhodamine, exceeding that of pure BiOCl and P25 by a factor of 6.10 and 19.74, respectively. The density functional theory (DFT) calculation was carried out to estimate the band structural and electronic properties of samples. Based on systematic analysis, the underlying mechanism was attributed to the extended responsive light range due to the surface plasma resonance of metallic Bi and the formation of oxygen vacancy energy level. Moreover, the electron sink effect of Bi nanoparticles was found to suppress the recombination of photoinduced charges, further contributing to the enhanced photocatalytic performance of Bi/BiOCl.