Enhanced Photocatalytic Activity of Nickel(II)-Doped Bi2O2CO3 Nanosheets for Efficient Nitric Oxide Removal

Graphical The photocatalytic efficiency of the optimized Ni 2+ -Bi 2 O 2 CO 3 for ppb-level NO under visible light irradiation is 59.4 %, which is 2.8 times than that of its counterpart, Bi 2 O 2 CO 3 (21.2 %). Furthermore, the introduction of nickel ions improves the photocatalytic performance of Ni 2+ -Bi 2 O 2 CO 3 , which not only lowered the bandgap, but also reduced the recombination of photogenerated carriers by formation of the impurity level. Bi 2 O 2 CO 3 is a typical bismuth-based semiconductor photocatalyst that has attracted much attention because of layered structure and polarization characteristics. However, the wide bandgap of Bi 2 O 2 CO 3 limits its practical applications in photocatalysis. In this study, the nickel (II)-doped Bi 2 O 2 CO 3 (Ni 2+ -Bi 2 O 2 CO 3 ) with oxygen vacancies was prepared by adding a controllable amount of nickel ions. The photocatalytic efficiency of the optimized sample for ppb-grade NO under visible light irradiation is 59.4 %, which is 2.8 times than that of its counterpart, Bi 2 O 2 CO 3 (21.2 %). Based on experiments and characterizations, Introduction of nickel ions and oxygen vacancies improves the photocatalytic performance of Ni 2+ -Bi 2 O 2 CO 3 , which not only lowered the bandgap from 3.25 eV to 2.92 eV, but also reduced the recombination of photogenerated carriers by formation of the impurity level. Furthermore, the adsorption and photocatalytic conversion pathway of NO was explored by in situ DRIFTS, the principal byproducts of photocatalytic oxidation of NO are NO 3 − and NO 2 − . This work offers a new perspective to improve the photocatalytic activity by doping mothed for air purification.