One-step hydrothermal synthesis of hierarchical nanosheet-assembled Bi₂O₂CO₃ microflowers with a {001} dominant facet and their superior photocatalytic performance

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.

Bi2O2CO3/Bi2O3 Z-scheme photocatalyst with oxygen vacancies and Bi for enhanced visible-light photocatalytic degradation of tetracycline

“…Moreover, it should be noted that the photocatalytic performance of the visible-light-driven Bi-BOC/BO-OVs photocatalytic system prevails over other photocatalytic systems (Table S4†). 16,46–51 The results revealed that the synergies between the heterojunction structure, OVs, and the SPR effect of Bi played a critical role in improving the photocatalytic performance.…”

“…Firstly, Bi 2 O 2 CO 3 was prepared by optimizing the experimental conditions according to previous methods and denoted as BOC. 16 Subsequently, the prepared precursor was calcined at different temperatures for 120 min at a heating rate of 3 °C min −1 under a N 2 atmosphere to obtain the target product. For comparison, a Bi 2 O 2 CO 3 /Bi 2 O 3 heterojunction photocatalyst (BOC/BO) without OVs and Bi nanoparticles was synthesized via a precursor calcined at 320 °C for 120 min in air.…”