Synthesis of mesoporous BiOI flower and facile in-situ preparation of BiOI/BiOCl mixture for enhanced photocatalytic degradation of toxic dye, Rhodamine-B

Potential application of bismuth oxyiodide (BiOI) when it meets light

Bismuth oxyiodide (BiOI) is a kind of typical two-dimensional (2D) material that has been increasingly developed alongside other 2D materials such as graphene, MXenes, and transition-metal dichalcogenide. However, its potential applications have not been widely whispered compared to those of other 2D materials. Using its distinctive properties, BiOI can be used for various applications, especially when it meets sunlight and other light-related electromagnetic waves. In this present review, we discuss the developments of BiOI and challenges in the applications for photodetector and light-assisted sensors, photovoltaic devices, optoelectronic logic devices, as well as photocatalysts. We start the discussion with a basic understanding and development of BiOI, crystal structure, and its properties. The synthesis and further development, such as green synthesis and its challenges in the synthesis-suited industry, as well as device integration, are also explained together with a plausible strategy to enhance the feasibility of BiOI for those various applications. We believe that the provided discussion and perspectives will not only promote BiOI to be one of the highly considered 2D materials but can also assist recent graduates in any materials science discipline and inform the senior scientists and industrial-based stakeholders of the latest advances in bismuth oxide and mixed-anion compounds.

Facile Synthesis and Characterizations of Mixed Metal Oxide Nanoparticles for the Efficient Photocatalytic Degradation of Rhodamine B and Congo Red Dyes

Photocatalytic degradation has been suggested to be a cheap and efficient way to dispose of organic pollutants, such as dyes. Therefore, our research team strives to produce nanophotocatalysts in a simple and inexpensive way. In this work, the Pechini sol-gel technique was employed for the facile synthesis of Mn_0.5Zn_0.5Fe₂O₄/Fe₂O₃ and Fe_0.5Mn_0.5Co₂O₄/Fe₂O₃ as mixed metal oxide nanoparticles for the efficient photocatalytic degradation of Rhodamine B and Congo Red dyes. XRD, FT-IR, a N₂ adsorption/desorption analyzer, EDS, FE-SEM, and an UV-Vis diffuse reflectance spectrophotometer were used to characterize the produced samples. The XRD patterns revealed that the average crystallite size of the Fe_0.5Mn_0.5Co₂O₄/Fe₂O₃ and Mn_0.5Zn_0.5Fe₂O₄/Fe₂O₃ samples is 90.25 and 80.62 nm, respectively. The FE-SEM images revealed that the Fe_0.5Mn_0.5Co₂O₄/Fe₂O₃ sample consists of cubic and irregular shapes with an average diameter of 1.71 µm. Additionally, the Mn_0.5Zn_0.5Fe₂O₄/Fe₂O₃ sample consists of spherical shapes with an average diameter of 0.26 µm. The energy gaps of the Fe_0.5Mn_0.5Co₂O₄/Fe₂O₃ and Mn_0.5Zn_0.5Fe₂O₄/Fe₂O₃ samples are 3.50 and 4.3 eV and 3.52 and 4.20 eV, respectively. In the presence of hydrogen peroxide, the complete degradation of 100 mL of 20 mg/L of Rhodamine B and Congo Red dyes occurred at pH = 8 and 3, respectively, within 50 min, using 0.1 g of the synthesized samples.

Effect of the presence of various natural organic matters on anodic oxidation of electrified carbon nanotube membrane

The widespread adoption of electrified carbon nanotube membranes (ECM) requires to better understand process effectiveness according to limiting phenomena of natural organic matters (NOMs). In this study, the influences of various NOM fractions were investigated on the oxidative degradation of Rhodamine B (RhB) in ECM. The results showed the decolorizing efficiencies of RhB in the presence of humic acid (HA) were still above 96%, while bovine serum albumin (BSA) reduced firstly and then increased the decolorizing efficiencies of RhB. The decolorizing efficiencies of RhB with alginate (AA) were over 98% at the first 15 min but decreased gradually to 76% after 150 min. These different performances of HA, BSA and AA were mainly due to their influences on the electrochemical reactivity characterization of ECM. ECM with the BSA depositing layer showed the highest exchange current density (j₀), while the AA depositing layer restrained electron-transfer activity of ECM. Cyclic voltammetry (CV) experiments showed that the partial electrooxidation of BSA would occur in ECM with its degradation product observed in the effluent. The variation of electrochemical reactivity characterization of ECM resulted into its electri-oxidation and electri-adsorption rates to be the largest with BSA, followed by AA and HA.