Acetaminophen oxidation under solar light using Fe-BiOBr as a mild Photo-Fenton catalyst

Acetaminophen is an analgesic used as a first-choice treatment for pain and fever. When individuals consume acetaminophen, a portion of the drug is excreted through urine and can end up in wastewater. Water remediation from pharmaceuticals, such as acetaminophen, is required before reaching the environment. This work demonstrates that Fe–BiOBr using the solar photo-Fenton process eliminates acetaminophen at mild pH in aqueous media. Fe-BiOBr is produced using microwave-assisted solvothermal synthesis, and the formation of the BiOBr phase is confirmed with XRD. SEM and TEM demonstrated the flower-like morphology, in which crystallite size reduces as a function of the Fe loading. The chemical environment at the surface of Fe–BiOBr is investigated with XPS. The results are connected with Raman analysis, which suggests the presence of oxygen vacancies in Fe–BiOBr. Furthermore, the effect of Fe in BiOBr is assessed by determining the optical band gap with UV–Vis. The Fe-BiOBr functionality is assessed during acetaminophen degradation. Fe-BiOBr revealed excellent performance in degrading acetaminophen in the first minutes (Q = 10 kJ m −2) under natural sunlight. Results reveal that 1% Fe content in BiOBr can degrade acetaminophen and its main byproduct (30 min, Q = 50 kJ m −2) at pH 5 and using 0.25 gL -1 of catalyst. A synergistic mechanism between heterogeneous photocatalysis and Fenton processes with primary superoxide ( •O 2 –) radical, followed by hydroxyl ( •OH) radical and photogenerated holes (h +), is proposed. Our research contributes to the degradation of pharmaceuticals under mild conditions and sunlight irradiation.</p

Unmanned aircraft systems as a new source of disturbance for wildlife: A systematic review.

The use of small Unmanned Aircraft Systems (UAS; also known as "drones") for professional and personal-leisure use is increasing enormously. UAS operate at low altitudes (<500 m) and in any terrain, thus they are susceptible to interact with local fauna, generating a new type of anthropogenic disturbance that has not been systematically evaluated. To address this gap, we performed a review of the existent literature about animals' responses to UAS flights and conducted a pooled analysis of the data to determine the probability and intensity of the disturbance, and to identify the factors influencing animals' reactions towards the small aircraft. We found that wildlife reactions depended on both the UAS attributes (flight pattern, engine type and size of aircraft) and the characteristics of animals themselves (type of animal, life-history stage and level of aggregation). Target-oriented flight patterns, larger UAS sizes, and fuel-powered (noisier) engines evoked the strongest reactions in wildlife. Animals during the non-breeding period and in large groups were more likely to show behavioral reactions to UAS, and birds are more prone to react than other taxa. We discuss the implications of these results in the context of wildlife disturbance and suggest guidelines for conservationists, users and manufacturers to minimize the impact of UAS. In addition, we propose that the legal framework needs to be adapted so that appropriate actions can be undertaken when wildlife is negatively affected by these emergent practices

Secondary crystalline phases identification in Cu2ZnSnSe4 thin films: contributions from Raman scattering and photoluminescence

In this work, we present the Raman peak positions of the quaternary pure selenide compound Cu2ZnSnSe4 (CZTSe) and related secondary phases that were grown and studied under the same conditions. A vast discussion about the position of the X-ray diffraction (XRD) reflections of these compounds is presented. It is known that by using XRD only, CZTSe can be identified but nothing can be said about the presence of some secondary phases. Thin films of CZTSe, Cu2SnSe3, ZnSe, SnSe, SnSe2, MoSe2 and a-Se were grown, which allowed their investigation by Raman spectroscopy (RS). Here we present all the Raman spectra of these phases and discuss the similarities with the spectra of CZTSe. The effective analysis depth for the common back-scattering geometry commonly used in RS measurements, as well as the laser penetration depth for photoluminescence (PL) were estimated for different wavelength values. The observed asymmetric PL band on a CZTSe film is compatible with the presence of CZTSe single-phase and is discussed in the scope of the fluctuating potentials’ model. The estimated bandgap energy is close to the values obtained from absorption measurements. In general, the phase identification of CZTSe benefits from the contributions of RS and PL along with the XRD discussion.info:eu-repo/semantics/publishedVersio

Atmospheric pressure chemical vapour deposition of transition metal selenide thin films

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Dual Application of (Aqua)(Chlorido)(Porphyrinato)Chromium(III) as Hypersensitive Amine-Triggered ON Switch and for Dioxygen Activation

Although synthesis and substitution reactions of chlorido chromium­(III) porphyrins Cr^III(TPP)­(Cl)­(L) (H₂TPP = 5,10,15,20-tetraphenyl porphyrin, L = pyridine, H₂O, ROH, etc.), have been well-established in coordination chemistry for decades, an unexpected dichotomous reactivity of Cr^III(TPP)­(Cl)­(H₂O) (<b>1</b>) toward amines is disclosed here. This reactivity leads to the application of <b>1</b> as highly sensitive substoichiometric and irreversible ON switch for amine detection by an autocatalytic pathway. The concomitant activation of O₂ by the <b>1</b>/amine system is furthermore exploited in an electrochemically driven epoxidation of norbonene using O₂ as initial oxidant

Photocatalytic Anatase TiO₂ Thin Films on Polymer Optical Fiber Using Atmospheric-Pressure Plasma

Due to the undeniable industrial advantages of low-temperature atmospheric-pressure plasma processes, such as low cost, low temperature, easy implementation, and in-line process capabilities, they have become the most promising next-generation candidate system for replacing thermal chemical vapor deposition or wet chemical processes for the deposition of functional coatings. In the work detailed in this article, photocatalytic anatase TiO₂ thin films were deposited at a low temperature on polymer optical fibers using an atmospheric-pressure plasma process. This method overcomes the challenge of forming crystalline transition metal oxide coatings on polymer substrates by using a dry and up-scalable method. The careful selection of the plasma source and the titanium precursor, i.e., titanium ethoxide with a short alkoxy group, allowed the deposition of well-adherent, dense, and crystalline TiO₂ coatings at low substrate temperature. Raman and XRD investigations showed that the addition of oxygen to the precursor’s carrier gas resulted in a further increase of the film’s crystallinity. Furthermore, the films deposited in the presence of oxygen exhibited a better photocatalytic activity toward methylene blue degradation assumedly due to their higher amount of photoactive {101} facets

Atmospheric Pressure Plasma-Initiated Chemical Vapor Deposition (AP-PiCVD) of Poly(alkyl acrylates): An Experimental Study

A novel atmospheric pressure plasma-initiated chemical vapor deposition (AP-PiCVD) approach toward the growth of conventional polymer layers is characterized and interpreted. A set of three methacrylate monomers (methyl, butyl, and glycidyl methacrylate) were investigated using ultrashort plasma discharges (ca. 100 ns) pulsed at various frequencies, covering a range of duty cycle from 0.1% to 0.000 316%. An unprecedented weight-average molar mass of 94 000 g mol^–1 coupled to an outstanding thin film conformality and an excellent chemical functionalities retention was achieved for the best deposition conditions. Insights into the growth mechanisms in AP-PiCVD and their dependence on the monomer’s intrinsic properties are provided

Robust bio-inspired antibacterial surfaces based on the covalent binding of peptides on functional atmospheric plasma thin films

peer reviewe

Heterometallic Porphyrin Conjugated Polymer Thin Films—A Gas‐Phase Approach for the Engineering of New Fused Porphyrin Systems

Abstract For the first time, the simultaneous synthesis and deposition of heterometallic porphyrin conjugated polymer thin films from a simple and scalable gas‐phase approach are reported. The oxidative chemical vapor deposition (oCVD) reaction of 5,15‐(diaryl) porphyrins chelated with different metal cations (M = Co(II), Ni(II), Zn(II), Cu(II), Pd(II)) readily yields the formation of new hetero‐metalated fused porphyrin tapes, such as evidenced by in‐depth high‐resolution mass spectrometry studies. The impact of the coreactants on the regioselectivity of the intermolecular dehydrogenative coupling reaction and the formation of double or triple bonds between the porphyrin units is demonstrated. The oCVD reaction of multiple porphyrins brings the possibility to easily engineer the chemical features and the electronic and optoelectronic properties of these highly conjugated porphyrin polymers. Particularly, it is demonstrated that porphyrin conjugated polymers having different chelated metal cations can achieve higher electrical conductivities and promote narrower bandgaps. The gas‐phase approach presented herein overcomes the main limitations of the conventional solution‐based approaches and opens the path to the engineering of a novel class donor–acceptor heterometallic polymers with high interest in several fields including multimetallic electrocatalysis, photocatalysis, sensing, and nonlinear optics applications

Chromium oxyselenide solid solutions from the atmospheric pressure chemical vapour deposition of chromyl chloride and diethylselenide

A new chromium oxyselenide solid-solution series Cr(2)O(3-x)Se(x) (x = 0, 0.1, 0.15, 0.2, 0.3, 0.4, 0.5, 0.7, 1.5, 2.15) was formed by the atmospheric pressure chemical vapour deposition of chromyl chloride and diethylselenide at 600 degrees C. The level of selenium incorporation was directly related to the gas-phase molar flows of reagents. There was a crossover in structure type adopted by the chromium oxyselenide with selenium incorporation, at x = 0-0.2 the solid solution crystallises in the Cr(2)O(3) structure type, at x = 0.3-2.15 it adopts the Cr(2)Se(3) structure type. All of the chromium oxyselenides were antiferromagnets. They showed a variation in Neel temperature with composition with a minimum temperature of 11 K observed for x = 0.7