Eu doped g-C3N4 nanosheet coated on flower-like BiVO4 powders with enhanced visible light photocatalytic for tetracycline degradation

In present work, Eu-CN@BiVO4 core-hell heterojunction photocatalyst was successfully synthesized via exfoliating the bulk Eu doped g-C3N4 to nanosheet and then coating on the surface of flower-like BiVO4 via sonication impregnation and heating process. The samples were characterized by serials measurements including XRD, FT-IR, SEM, EDS, TEM, HRTEM, XPS, UV-vis DRS, BET, and PL. The results showed that this synthesis method can easily and tightly make g-C3N4 or Eu doped g-C3N4 nanosheet being combined with flower-like BiVO4 to form a core-hell heterojunction structure, which benefited in the charge transfer across the interface of CN (or Eu-CN) and BiVO4. And from the photocatalytic activity test, there are only about 65% of tetracycline (TC) being photodegraded in 50 min over BiVO4, but 90.79% of TC in 50 min over CN@BiVO4, and 92.1% of TC in 30 min over Eu-CN@BiVO4. The Eu-CN@BiVO4 photocatalyst has much higher photocatalytic than CN@BiVO4 due to the presence of Eu(III) in Eu-CN@BiVO4 capture photoinduced electrons and achieve the elevated photoinduced electron-hole transferring and separation rate, further to lead to superior photocatalytic efficiency.