One-step hydrothermal synthesis of hierarchical nanosheet-assembled Bi <sub>2</sub> O <sub>2</sub> CO <sub>3</sub> microflowers with a {001} dominant facet and their superior photocatalytic performance
Xiaoyan Yang, Yonglin Wang, Na He, Wubo Wan, Fuli Zhang, Bin Zhai, Peng Zhang
Abstract
Abstract Using citric acid (CA) and 1,5-naphthalenedisulfonic acid (NDSA) as the structure-directing agent, a hierarchical flower-like Bi 2 O 2 CO 3 product is successfully prepared via a simple one-step hydrothermal synthesis, which is spirally assembled by the {001} facet-dominated nanosheets. It is testified that the additive CA plays an important inducing role in forming the chemical composition of Bi 2 O 2 CO 3 , the nanosized sheet-type subunits, and the exposure of the {001} facet, while the NDSA greatly improves the dispersity and porous structure of the Bi 2 O 2 CO 3 microflower. Due to the nano-size effect and distortion of surface Bi-O bonds, the Bi 2 O 2 CO 3 microflower could be excited by the visible light to exhibit a superior photocatalytic performance in the degradation of tetracycline (TC). Besides, it is found the exposed {001} facet of Bi 2 O 2 CO 3 would preferentially generate holes during the illumination process, thus enhancing the photooxidative activity of the Bi 2 O 2 CO 3 microflower. Finally, the structural and optical features of the Bi 2 O 2 CO 3 microflower have been discussed in detail, and its photocatalytic mechanism has also been proposed in this work.