In-situ fabrication of 0D/2D NiO/Bi12O17Cl2 heterojunction towards high-efficiency degrading 2, 4-dichlorophenol and mechanism insight

Enhanced biodegradation of 2, 4-dichlorophenol in packed bed biofilm reactor by impregnation of polyurethane foam with Fe3O4 nanoparticles: Bio-kinetics, process optimization, performance evaluation and toxicity assessment

In this work, an effort has been made to enhance the efficacy of biological process for the effective degradation of 2, 4-dichlorophenol (2, 4-DCP) from wastewater. The polyurethane foam was modified with Fe3O4 nanoparticles and combined with polyvinyl alcohol, sodium alginate, and bacterial consortium for biodegradation of 2, 4-DCP in a packed bed biofilm reactor. The maximum removal efficiency of 2, 4-DCP chemical oxygen demand, and total organic carbon were found to be 92.51 ± 0.83 %, 86.85 ± 1.32, and 91.78 ± 1.24 %, respectively, in 4 days and 100 mg L-1 of 2, 4-DCP concentration at an influent loading rate of 2 mg L-1h-1 and hydraulic retention time of 50 h. Packed bed biofilm reactor was effective for up to four cycles to remove 2, 4-DCP. Growth inhibition kinetics were evaluated using the Edward model, yielding maximum growth rate of 0.45 day-1, inhibition constant of 110.6 mg L-1, and saturation constant of 62.3 mg L-1.

Oxygen vacancies mediated Bi12O17Cl2 ultrathin nanobelts: Boosting molecular oxygen activation for efficient organic pollutants degradation

Photocatalysis technology has been considered as a sustainable and promising strategy for pollutant degradation. However, the photocatalytic activity is limited by the unsatisfactory carrier separation efficiency of photocatalysts and insufficient reactive oxygen species. Herein, the oxygen vacancies (OVs) mediated Bi₁₂O₁₇Cl₂ ultra-thin nanobelt (ROV Bi₁₂O₁₇Cl₂) was fabricated via solvothermal method. The surface oxygen vacancies can act as the 'electron sink' and boost charge separation. Thus, the ROV Bi₁₂O₁₇Cl₂ shows superior photocatalytic performance, which is 2.72 and 4.52 times compared to deficient oxygen vacancies Bi₁₂O₁₇Cl₂ (DOV Bi₁₂O₁₇Cl₂) and Bulk Bi₁₂O₁₇Cl₂ for colored organic pollutants degradation, respectively. Besides, the ROV Bi₁₂O₁₇Cl₂ also displays excellent removal efficiency for refractory antibiotics, roughly 4.00 and 7.45 times compared to that of DOV Bi₁₂O₁₇Cl₂ and Bulk Bi₁₂O₁₇Cl₂, respectively. Furthermore, the intermediates for photocatalytic degradation were determined through HPLC-MS and the possible degradation paths of the target molecules were inferred. Capture experiment and ESR spectra confirmed that the ^•O₂^- played a vital role for the organic pollutant degradation. This work provides a new perspective for the design of advanced semiconductors for organic pollutants degradation.

3D NiO nanoflakes/carbon fiber meshwork: Facile preparation and utilization as general platform for photocathodic bioanalysis

Herein, we describe a customized approach for facile preparation of three-dimensional (3D) NiO nanoflakes (NFs)/carbon fiber meshwork (CFM) and its validation as a common photocathode matrix for photoelectrochemical (PEC) bioanalysis, which to our knowledge has not been reported. Specifically, 3D NiO NFs/CFM was fabricated by a sequential liquid phase deposition and annealing process, which was then characterized by scanning electron microscopy, X-ray photoelectron spectrum, UV-vis absorption spectra and N₂ adsorption-desorption measurement. Sensitized by BiOI and incorporated with an alkaline phosphatase (ALP)/tyrosinase (TYR) bi-enzyme cascade system, a sensitive split-type cathodic PEC bioanalysis for the determination of ALP was achieved. This method can detect ALP concentrations down to 3 × 10^-5 U L^-1 with a linear response range of 0.001-10 U L^-1. Moreover, this proposed system exhibited good selectivity, stability and excellent performance for real sample analysis. This research features the facile preparation of 3D NiO NFs/CFM that could acts as a universal matrix for photocathodic analysis, and is envisioned to stimulate more effort for advanced 3D photocathode for PEC bioanalysis and beyond.

2D/1D Bi12O17Cl2/β-Bi2O3 heterojunction photocatalysts with boosted photocatalytic performance

A novel 2D/1D Bi₁₂O₁₇Cl₂/β-Bi₂O₃ heterostructure displays excellent photocatalytic degradation of methyl orange and phenol under solar light irradiation. The enhanced photocatalytic activity is ascribed to the unique vertical 2D Bi₁₂O₁₇Cl₂ nanosheets.

Effect of carbon nanotubes loading on the photocatalytic activity of BiSI/BiOI as a novel photocatalyst

In this paper, a simple hydrothermal method is employed to synthesize BiSI/BiOI/CNT nanocomposite with enhanced photocatalytic activity. The properties of the prepared samples were studied using nitrogen adsorption-desorption isotherm, photoluminescence, X-ray diffraction analysis (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive spectrometry (EDS), UV-vis diffuse reflectance spectroscopy (DRS), and electrochemical impedance spectroscopy (EIS). The loading amount of CNT had a significant influence on the photoactivity of the BiSI/BiOI/CNT composite. In this study, several BiSI/BiOI/CNT nanocomposite samples with various mass ratios of CNT were made-up for further investigation to scrutinize the influence of CNT content on the photocatalytic activity of the nanocomposite. Photocatalysis measurements revealed that 2% Wt of CNT possesses the highest photocatalytic activity in the visible light irradiation with 93.1% photodegradation of malachite green (MG) as a test dye. The enhanced photocatalytic performance can be due to the large surface area, excellent conductivity performance, and high absorption ability in the visible light region. The synergistic effect of the factors mentioned above makes BiSI/BiOI/CNT nanocomposite a high-performance photocatalyst under visible light irradiation. An appropriate reaction mechanism of dye photodegradation has suggested according to the result of active species trapping experiments.