Synthesis of Co3O4 Nanoparticles-Decorated Bi12O17Cl2 Hierarchical Microspheres for Enhanced Photocatalytic Degradation of RhB and BPA

Abstract

Three-dimensional (3D) hierarchical microspheres of Bi12O17Cl2 (BOC) were prepared via a facile solvothermal method using a binary solvent for the photocatalytic degradation of Rhodamine-B (RhB) and Bisphenol-A (BPA). Co3O4 nanoparticles (NPs)-decorated BOC (Co3O4/BOC) heterostructures were synthesized to further enhance their photocatalytic performance. The microstructural, morphological, and compositional characterization showed that the BOC microspheres are composed of thin (~20 nm thick) nanosheets with a 3D hierarchical morphology and a high surface area. Compared to the pure BOC photocatalyst, the 20-Co3O4/BOC heterostructure showed enhanced degradation efficiency of RhB (97.4%) and BPA (88.4%). The radical trapping experiments confirmed that superoxide (•O2−) radicals played a primary role in the photocatalytic degradation of RhB and BPA. The enhanced photocatalytic performances of the hierarchical Co3O4/BOC heterostructure are attributable to the synergetic effects of the highly specific surface area, the extension of light absorption to the more visible light region, and the suppression of photoexcited electron-hole recombination. Our developed nanocomposites are beneficial for the construction of other bismuth-based compounds and their heterostructure for use in high-performance photocatalytic applications.

Composite Photocatalysts with Fe, Co, and Ni Oxides on Supports with Tetracoordinated Ti Embedded into Aluminosilicate Gel during Zeolite Y Synthesis

“…where ECB is CB potential, EVB is VB potential, and Eg is band gap energy [73]. So, the obtained CB potentials for the samples were 0.88 eV for 2TYF, 0.94 eV for 2TYC, and −2.27 eV for 2TYN.…”

“…As illustrated in Figure 16, the photogenerated electrons reduce O 2, producing superoxide (•O 2 − ) radicals, while the separated holes oxidize H 2 O molecules, forming hydroxyl (•OH) radicals in the system. These two reactive oxygen species thus obtained are considered to be the main ones involved in the photocatalytic degradation of organic pollutants in water [73,80,84]. To further investigate the degradation mechanism and to clarify the role of each reactive species, scavenger experiments were carried out.…”

Flower‐Like Ag6Si2O7/Bi12O17Cl2 p‐n Heterojunctions: Enhanced Photocatalytic Activity and Mechanistic Insight**

“…[31] When Ag alone are determined to be 3.06 and 2.28 eV vs. NHE, respectively. According to the empirical formula E CB = E VB À E g , [32] combined with the results of E g in DRS, the E CB for Ag [9] CoFe 2 O 4 / Bi 12 O 17 Cl 2 -3, [11] 20-Co 3 O 4 / Bi 12 O 17 Cl 2 , [33] Bi 12 O 17 Cl 2 /g-C 3 N 4 [34] and other types of photocatalysts such as ZnO/CdS, 3 g-C 3 N 4 / BaBiO 3 . [35] In order to facilitate comparison, the degradation processes of RhB over Ag 6 Si 2 O 7 , Bi 12 O 17 Cl 2 and Ag 6 Si 2 O 7 / Bi 12 O 17 Cl 2 composites were further analyzed through first order kinetic equation (Figure 7B).…”

Composite Photocatalysts with Fe, Co, Ni Oxides on Supports with Tetracoordinated Ti Embedded into Aluminosilicate Gel during Zeolite Y Synthesis

“…As illustrated in Figure 14, the photogenerated electrons reduce O2 producing superoxide (•O2 -) radicals, while the separated holes oxidize H2O molecules, forming hydroxyl (•OH) radicals in the system. These two reactive oxygen species thus obtained are considered to be the main ones involved in the photocatalytic degradation of organic pollutants in water [70][71][72]. To further investigate the degradation mechanism and to clarify the role of each reactive species, scavenger experiments were carried out.…”