Investigation of electrocatalytic and photocatalytic ability of Cu/Ni/TiO2/MWCNTs Nanocomposites for detection and degradation of antibiotic drug Furaltadone

WSe2-PPy-Based Type-II Heterostructure for Efficient Photocatalytic Removal of Nitrofurazone

The escalating concerns over water pollution and antimicrobial resistance have underscored the urgency of effective antibiotic degradation. Photocatalytic degradation offers a promising solution due to its efficiency and environmental friendliness. In this study, I synthesized a novel nanocomposite comprising WSe2 and polypyrrole (PPy) via a hydrothermal method coupled with polymerization for the degradation of nitrofurazone antibiotics. The WSe2/PPy nanocomposite demonstrated significantly higher photocatalytic degradation efficiency (94.50%) compared to pure WSe2 and PPy, with degradation efficiencies of 23.07% and 32.96%, respectively. The degradation was performed at different pH values, with acidic conditions proving the most suitable for nitrofurazone degradation. The photocatalytic degradation efficiencies at pH 2, 3, 5, 7, 9, and 11 were 98.5%, 98.3%, 85.4%, 78.02%, 61.4%, and 61%, respectively. The acidic conditions were found to be the most suitable for nitrofurazone degradation. The nanocomposite's improved efficiency was ascribed to its low recombination rate and quick charge transfer, as demonstrated by time-resolved photoluminescence (TRPL) and electrochemical impedance spectroscopy (EIS) tests, respectively. The Z-Scheme photocatalysis mechanism as proposed for the WSe2-PPy nanocomposite and supported by scavenger experiments. Moreover, the nanocomposite demonstrated excellent reusability, which enhanced its practical applicability.

Surface-designed AuNPs-based fluorescent probe for ultra-sensitive detection of oral poultry antibacterial drug furaltadone via intermolecular hydrogen bonding

Furaltadone (FTD), a nitrofuran drug, was primarily utilized as a very effective oral veterinary antibiotic, especially in poultry production farms. As a result, FTD, a form of carcinogen, might easily enter people via the food chain, leading to fatal cancers. As a result, it is critical to develop a quick and efficient approach for detecting FTD at extremely low concentrations. Considering the aforementioned purpose, pamoic acid (PA) capped gold nanoparticles (PA@AuNPs) were synthesized in spherical morphology (size 10-15 nm) using the method of chemical reduction and used as a fluorescent probe to detect FTD. The interaction between PA@AuNPs and FTD was validated by UV-vis, XRD, and FTIR methods. Microscopic images (FESEM and HRTEM) show that PA@AuNPs have varying morphologies including rod, triangle, hexagonal, and pentagonal, and average sizes of 20-50 nm after sensing FTD. The average surface roughness of PA@AuNPs was determined to be 46.75 nm using the AFM technique. The addition of FTD (0 → 100 μM) quenched the fluorescence emission intensity of PA@AuNPs at 436 nm (λ ex 353 nm) by 4-fold. This static quenching was confirmed by the formation of a ground state complex, PA@AuNPs·FTD, between AuNPs and FTD using fluorescence lifetime analysis. The presence of an isosbestic point at 412 nm in the UV-visible titration, as well as FTIR data, further demonstrated the existence of this ground state complex. PA@AuNPs revealed high sensitivity (LoD = 9.78 nM; K a = 1.0615 × 102 M-1) to FTD in water, resulting in a decrease in predicted quantum yield (Φ F) from 3.36% to 0.35%. To establish PA@AuNPs as a first-generation fluorescence probe for real samples, FTD in blood serum was measured (LoD = 6.07 nM; K a = 1.0595 × 102 M-1). The non-toxic cytotoxicity and bioimaging in live zebrafish broadened the practical uses of PA@AuNPs. Furthermore, the surface interactions between PA@AuNPs and FTD were studied theoretically using time-dependent density functional theory (TD-DFT) at the B3LYP/6-31G(d,p) level of theory to support the findings from the experiment.

Blue-emitting tryptophan-protected gold nanoclusters acted as a sensitive nanosensor for fluorescence sensing and visual imaging detection of furaltadone

Herein, blue-emitting gold nanoclusters (Au NCs) were carried out through tryptophan as the protecting and reducing agents. In aqueous solution of Au NCs@tryptophan, the addition of furaltadone guaranteed the interaction of furaltadone with tryptophan around Au NCs. The propinquity of furaltadone to Au NCs caused that the fluorescence of Au NCs was weakened by furaltadone based on the inner filter effect (IFE). Under the optimal measurement conditions, the logarithm of relative fluorescence intensity of Au NCs@tryptophan was linearly carried out with the furaltadone amount increasing from 0.5 to 100 μM, the corresponding detection limit was 0.087 μM. The fluorescence change of Au NCs@tryptophan displayed excellent selectivity and sensitivity for furaltadone than other possible substance in the human body. In view of Au NCs@tryptophan, the as-performed fluorescence nanosensor suggested outstanding ability for furaltadone sensing in real samples. Obviously, this nanoprobe of furaltadone could implement the naked-eye visual fluorescence determination of furaltadone.

Photocatalytic removal of 17β-estradiol from water using a novel bimetallic NiCu/Nb2O5 catalyst

The development of effective photocatalytic materials is essential for removing emerging pollutants from aqueous media, such as the hormone 17β-estradiol (E2). In this study, a novel photocatalyst based on niobium pentoxide (Nb2O5) functionalized with nickel (Ni) and copper (Cu) was synthesized for E2 removal. The NiCu/Nb2O5 photocatalyst was prepared using a facile wet impregnation method and characterized by various techniques. The incorporation of Ni and Cu into Nb2O5 reduced the band gap energy from 3.3 to 2.8 eV, enabling efficient utilization of visible light. Moreover, NiCu/Nb2O5 exhibited the highest E2 removal efficiency (82%) under UV-A-assisted conditions at a concentration of 1.5 g L-1. The reaction kinetics were found to follow a second-order model with a rate constant of k = 0.0020 L g-1 min-1, and a plausible reaction mechanism was proposed. Through the study of radical elimination, it was proven that the radical oxidation reaction mechanism predominated in the reaction. The results of the toxicity assays, combined with the TOC parameter, demonstrated the efficacy of photocatalytic degradation in reducing E2. These findings demonstrate the great potential of the NiCu/Nb2O5 photocatalyst for removing persistent pollutants.

Facile synthesis of core-shell Co-MOF with hierarchical porosity for enhanced electrochemical detection of furaltadone in aquaculture water

Metal-organic frameworks (MOFs) exhibited huge application potential in electrochemical analysis field, how to facilely and effectively boost the electrochemical sensing activity of MOFs materials still face enormous challenges. In this work, core-shell Co-MOF (Co-TCA@ZIF-67) polyhedrons with hierarchical porosity was easily synthesized via simple chemical etching reaction by selecting thiocyanuric acid as the etching reagent. Benefiting from the introduction of mesopores and thiocyanuric acid/Co²⁺ complex on the surface of ZIF-67 frameworks, the property and functions of the pristine ZIF-67 was seriously tailored. Compared with the pristine ZIF-67, the as-resulted Co-TCA@ZIF-67 nanoparticles displayed greatly enhanced physical adsorption capacity and electrochemical reduction activity toward the antibiotic drug furaltadone. As a result, a novel furaltadone electrochemical sensor with high sensitivity was fabricated. The linear detection range was from 50 nM to 5 μM with sensitivity of 110.40 μA^-1 μM^-1 cm^-2 and detection limit of 12 nM. This work demonstrated chemical etching strategy is truly a facile and effective way to modify the electrochemical sensing performance of MOFs-based materials, and we believed the chemically etched MOFs materials will play a stronger role in terms of food safety and environmental conservation.

Role of polymer template in crystal structure and photoactivity of Cu-TiO2 heterojunction nanostructures towards environmental remediation

Exploring porous heterojunction nanomaterials as a photocatalyst for water depollution strategies towards environmental restoration is exceedingly difficult in the perspective of sustainable chemistry. Herein, we first report a porous Cu-TiO₂ (TC40) heterojunction by using microphase separation of a novel penta-block copolymer (PLGA-PEO-PPO-PEO-PLGA) as a template through an evaporation induced self-assembly (EISA) method having nanorod-like particle shape. Furthermore, three types of photocatalysts were made with or without template polymer to clarify the function of that template precursor on the surface and morphology, as well as which variables are the most critical for a photocatalyst. TC40 heterojunction nanomaterial displayed high BET surface area along with lower band gap value viz.2.98 eV compare the other and all of these features make it a robust photocatalyst for wastewater treatment. In order to improve water quality, we have carried out experiments on the photodegradation of methyl Orange (MO), highly toxic pollutants that cause health hazards and bioaccumulate in the environment. Our catalyst, TC40 exhibits the 100% photocatalytic efficiency towards MO dye degradation in 40 and 360 min at a rate constant of 0.104 ± 0.007 min^-1 and 0.440 ± 0.03 h^-1 under UV + Vis and visible light irradiation respectively.

Hierarchical 3D Snowflake-like Iron Diselenide: A Robust Electrocatalyst for Furaltadone Detection

An electrocatalyst with a large active site is critical for the development of a high-performance electrochemical sensor. This work demonstrates the fabrication of an iron diselenide (FeSe₂)-modified screen-printed carbon electrode (SPCE) for the electrochemical determination of furaltadone (FLD). It has been prepared by the facile method and systematically characterized with various microscopic/spectroscopic approaches. Due to advantageous physiochemical properties, the FeSe₂/SPCE showed a low charge-transfer resistance value of 200 Ω in 5.0 mM [Fe(CN)₆]^3-/4- containing 0.1 M KCl. More importantly, the FeSe₂/SPCE exhibited superior catalytic performance compared to the bare SPCE for FLD sensing based on the electrochemical response in terms of a peak potential of -0.44 V (vs Ag/AgCl (sat. KCl)) and cathodic response current of -22.8 μA. Operating at optimal conditions, the FeSe₂-modified electrode showed wide linearity from 0.01 to 252.2 μM with a limit of detection of 0.002 μM and sensitivity of 1.15 μA μM^-1 cm^-2. The analytical performance of the FeSe₂-based platform is significantly higher than many previously reported FLD electrochemical sensors. Furthermore, the FeSe₂/SPCE also has a promising platform for FLD detection with high sensitivity, good selectivity, excellent stability, and robust reproducibility. Thus, the finding above shows that the FeSe₂/SPCE is a highly suitable candidate for the electrochemical determination of glucose levels for real-time applications such as in human urine and river water samples.

Mechanistic insight into the photocatalytic degradation of organic pollutants and electrochemical behavior of modified MWCNTs/Cu–Co3O4 nanocomposites

The present work reported the physical, chemical and electrical properties of Cu doped Co3O4.