In-Situ Hydrothermal Synthesis of Bi–Bi2O2CO3 Heterojunction Photocatalyst with Enhanced Visible Light Photocatalytic Activity

Abstract

Bismuth containing nanomaterials recently received increasing attention with respect to environmental applications because of their low cost, high stability and nontoxicity. In this work, Bi–Bi2O2CO3 heterojunctions were fabricated by in-situ decoration of Bi nanoparticles on Bi2O2CO3 nanosheets via a simple hydrothermal synthesis approach. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) were used to confirm the morphology of the nanosheet-like heterostructure of the Bi–Bi2O2CO3 composite. Detailed ultrafast electronic spectroscopy reveals that the in-situ decoration of Bi nanoparticles on Bi2O2CO3 nanosheets exhibit a dramatically enhanced electron-hole pair separation rate, which results in an extraordinarily high photocatalytic activity for the degradation of a model organic dye, methylene blue (MB) under visible light illumination. Cycling experiments revealed a good photochemical stability of the Bi–Bi2O2CO3 heterojunction under repeated irradiation. Photocurrent measurements further indicated that the heterojunction incredibly enhanced the charge generation and suppressed the charge recombination of photogenerated electron-hole pairs.

Halide‐Modulated Functionality of Wide Band Gap Zinc Oxide Semiconductor Nanoparticle

“…Upon excitation of lower energy than the band gap of the semiconductor, the rate of catalytic activity starts decreasing gradually. Insignificant photocatalysis activity at the wavelength of 460 nm (at MO absorbance maxima) indicates that photocatalysis is not influenced by the pollutant dye MO . The PEC action spectra of ZnO (for water oxidation reaction), as calculated from the photocurrent spectrum at different wavelength (from 250 nm to 500 nm) is shown in Figure b.…”

Synthesis, structural characterization, and photocatalytic activity of Bi‐based nanoparticles

“…Recently, nonnoble metal Bi nanoparticles were reported for improving the activity of semiconductor photocatalysts efficiently. Bi nanoparticles based heterojunctions with a semiconductor, Bi/Bi 2 O 2 CO 3 , Bi/BiOCl, etc., enhanced electron‐hole pair separation rate and improved the photocatalytic efficacies . The photogenerated electrons in 5Ag‐P sample would probably be transferred from Ag‐Bi 2 O 3 to Bi 2 O 2 CO 3 and finally to the Bi particles, promoting the separation of electrons and holes, effectively.…”

“…Bi nanoparticles based heterojunctions with a semiconductor, Bi/Bi 2 O 2 CO 3 , Bi/BiOCl, etc., enhanced electron-hole pair separation rate and improved the photocatalytic efficacies. 45,46 The photogenerated electrons in 5Ag-P sample would probably be transferred from Ag-Bi 2 O 3 to Bi 2 O 2 CO 3 and finally to the Bi particles, promoting the separation of electrons and holes, effectively. Degradation efficiency of 5Ag-P and 10Ag-P samples at 5 hours of irradiation exhibited an enhanced photocatalytic activity toward MB degrading comparing with P sample due to the effect of Bi as an efficient separator of electronhole pairs in these hybrid structures.…”

Defect State Modulation of TiO2 Nanostructures for Photocatalytic Abatement of Emerging Pharmaceutical Pollutant in Wastewater Effluent

“…[46] Here, we have used isopropanol (IPA) (ROS: hydroxyl radical), ascorbic acid (ROS: superoxide radical), and ammonium oxalate (AO) (ROS: hole and hydroxyl radical) as the ROS scavengers in order to illustrate the role of ROS during photocatalytic degradation of ANT. [47][48][49][50][51] The effect of such scavengers on the photocatalytic activity is shown in Figure 7c. Significant retardation of photocatalytic activity was observed after addition of IPA, AO, and ascorbic acid.…”