Multifunctional Bismuth Oxychloride/Mesoporous Silica Composites for Photocatalysis, Antibacterial Test, and Simultaneous Stripping Analysis of Heavy Metals

Abstract

The increasing complexity of environmental pollution nowadays poses a severe threat to the public health, which attracts considerable attentions in searching for nanomaterials of multiproperty. In this study, mesoporous silica of KIT-6-encapsulated bismuth oxychloride (BiOCl), an intrinsically multifunctional material exhibiting bunched structure in the composites, are facilely prepared under hydrothermal conditions. Subsequently, the produced materials of multifunctionality were applied for photocatalysis, antibacterial test, and simultaneous determination of heavy metals including lead and cadmium. A combination of physiochemical characterizations have revealed that the BiOCl–KIT-6 composites exhibit enlarged yet refined surface morphology contributing to the improved photocatalytic ability with a band gap of 3.06 eV at a molecular ratio of 8Bi–Si. Moreover, the antibacterial activities of our BiOCl–KIT-6 composites were explored, and possible antimicrobial mechanism related to the production of reactive oxygen species was discussed. Furthermore, a sensitive electrochemical determination of heavy metals of lead and cadmium using square-wave anodic stripping voltammetry was also achieved. The composites-modified glassy carbon electrode displays a linear range of calibration curve from 0.2 to 300 μg/L with a detection limit of 0.05 μg/L (Pb2+) and 0.06 μg/L (Cd2+), respectively.

Bi5+, Bi(3−x)+, and Oxygen Vacancy Induced BiOClxI1−x Solid Solution toward Promoting Visible‐Light Driven Photocatalytic Activity

“…Since symmetric vibrations usually give rise to more intense Raman bands than asymmetricv ibrations, the strong Ramanb ands observeda t6 4.7 and 144.8 cm À1 were assigned to the E g Bi-O-Cls tretching mode and A 1g BiÀCl stretching mode. [49,51] The strong Ramanb and at 200.7 cm À1 can be assigned to E g internal BiÀCl stretching, whereas the weak band at 397.4 cm À1 is due to the E g and B 1g modesb roughtb yt he motion of the oxygen atom. [27,50] Noticeably,t wo new Raman signals found in the vicinity of 98 cm À1 for BC andB C9 are caused by Bi (3Àx) + and Bi 5 + , [52] which are consistentw ith the XPS measurement.…”

Multifunctional Bismuth-Based Materials for Heavy Metal Detection and Antibiosis

“…Recently, bismuth-based sensors, exhibiting improved separation ability of intermetallic compounds, compared with mercury-based ones, have been used to evaluate heavy metals such as Cd 2+ and Pb 2+ . These toxic heavy metals originating from severe environmental conditions including mining area, smelting works, and sewage plant [12] are harmful for the public health.…”

“…Growth curves of S. aureus cultured in LB media containing 20 μg/mL BiOCl-KIT-6 composite suspension. Each data point is the average of three independent assays with standard error of the mean (adapted from Ref [12]…”

Enriched Ag Nanospecies Interspersed Nanoporous Siliceous Antibacterial Agent

“…Comparing the results of Figure A and Figure B, the antibacterial properties of mesoporous Ag‐NSA against E. coli were superior to that of S. aureus , which was attributed to their structural difference of cell wall and composition. For example, the presence of negatively charged lipopolysaccharides (LPS) in E. coli (G − ) may promote the interaction with weak positively charged silver nanospecies . Due to the identical amount of silver used in Ag‐NSA and exposed Ag treated groups, the total quantity of silver seemed not the crucial reason for the superior antibacterial properties of Ag‐NSA.…”