Applied Surface Science Advances最新文献

The article discusses the function of green nanoparticles in preventing corrosion of different alloys such as copper, zinc, steel, and aluminium alloys. Green nanoparticles are characterized by their environmentally friendly and sustainable production methods, which emphasize using natural materials. Environmental issues have long been linked to traditional corrosion inhibitors, which has led to a shift towards more environmentally friendly alternatives. A potential remedy for these issues is the use of green nanoparticles, which are derived from renewable and biodegradable resources. Green nanoparticles support sustainability goals and have strong corrosion inhibition properties. Their combined role makes them essential players in a future where environmental awareness and material safety coexist. The review envisages a significant paradigm shift in critical industrial contexts, which calls for a robust and ecologically friendly approach to corrosion prevention. Green nanoparticles can potentially transform the field of materials protection entirely, and their investigation as corrosion inhibitors opens up new directions for study and development. In conclusion, this review highlights the crucial role of these nanoparticles in creating a sustainable future where creative solutions will enhance industrial productivity and environmental well-being. Finally, the prospects and difficulties of sustainably applying green nanoparticles to corrosion inhibition have also been explored.

Electropolishing or electrochemical polishing (EP) is an ultrafinishing process that improves esthetic, technical and functional properties of metallic surfaces by reducing their roughness. This process is based on anodic dissolution of the workpiece through an oxidation reaction. For many years, cyanide-based electrolytes were used to electropolish precious metals like gold and its alloys. The need for safer working conditions encouraged the replacement of cyanide by other complexing agents, mainly thiourea. However, the latter is also harmful. Therefore, the aim of this work is to electropolish pure gold and 18k jewelry gold alloys (yellow, rose, red and gray) in a cyanide-free electrolyte, to evaluate the electrochemical behavior and the influence of different parameters. For this purpose, a previously reported solution based on hydrochloric acid and glycerol was used. In the first part of the study, the influence of chloride concentration on pure gold EP was determined by electrochemical techniques and surface properties analysis. The effects of adding ethanol to electrolyte composition and of variating rotation speed were also evaluated. The best results were obtained for a HCl 50% vol. - Glycerol 25 % vol. - Ethanol 25 % vol. electrolyte at a rotation speed of 1000 rpm. In the second part of the study, this solution was used to electropolish 18 K gold alloys. Silver-containing alloys were not uniformly polished due to the formation of an AgCl film on the surface that partially masks the substrates.

Breast cancer poses a significant health concern due to its increasing prevalence and mortality rates. Hence, prompt action is needed to develop innovative therapeutic interventions, as conventional treatments exhibit severe adverse effects and have limited efficacy. This study aims to develop an innovative therapeutic intervention for breast cancer using biosynthesized nanoceria. Nanoceria has gained significant importance in the medicinal field due to its biocompatibility, dual capabilities as both antioxidant and prooxidant, and specific cytotoxicity towards cancer cells. Herein, nanoceria was biosynthesized using Echinochloa frumentaceae grain extract (EFNC) due to its eco-friendly and cost-efficient nature, and it was systematically investigated using standard characterization techniques. Furthermore, their anticancer efficacy against MCF-7 breast cancer cell lines was studied using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cell viability assay, and the occurrence of apoptosis was determined using acridine orange/ethidium bromide (AO/EtBr) staining. Significantly, EFNC exhibited superior anticancer efficacy even at lower concentrations (10 µg/mL), and the IC₅₀ value was found at 47.32 µg/mL. In addition, the observed bright green and orange-red fluorescence, along with fragmented/condensed chromatin features in AO/EtBr staining clearly indicated that the EFNC caused cell death through the apoptotic route. One potential factor contributing to the observed anticancer effectiveness of EFNC could be its prooxidant properties within cancer cells. These properties ultimately enhanced oxidative stress, induced the accumulation of reactive oxygen species (ROS), and led to apoptosis. Hence, the in vitro analysis substantiated the significant anticancer efficacy of EFNC, suggesting its potential utility as a promising therapeutic agent in anticancer treatment. These findings pave the way for further exploration and development of EFNC as a valuable candidate for addressing cancer-related challenges.

This study presents a novel methodology for the rapid on-site detection of tannic acid (TA), a prevalent organic contaminant in various natural environments, notably in plant-derived sources. The proposed approach involves the development of a compact integrated electrochemical sensor incorporating a nanozyme system. Specifically, this system comprises Fe₂O₃ nanoparticles (NPs) embedded within a chitosan (CS) matrix, immobilized onto a sulfur-doped graphene (S-Gr) substrate deposited on a gold electrode (AuE). The Fe₂O₃NPs exhibit peroxidase-like artificial enzyme activity, contributing to exceptional stability and catalytic efficiency in TA oxidation processes. Additionally, the CS matrix acts as a stabilizing agent, enhancing the performance and recyclability of the nanozyme. Furthermore, the S-Gr nanomaterial facilitates rapid electron transfer, leading to heightened sensitivity and prompt response times. The integration of these advanced nanomaterials with a microfabricated electrode presents an economically feasible, reliable, and effective solution for TA detection, with promising prospects for large-scale deployment and environmental monitoring. The Fe₂O₃CS-S-Gr/AuE sensing system demonstrates a calculated limit of detection (LOD) of 3.6 × 10⁻³ µM and an increased sensitivity of 0.2 µA×µM⁻¹, with a wide linear concentration range spanning from 0.01 to 1000 µM for TA detection. Notably, the recovery values obtained for surface water samples fall within the range of 97.7 % to 99.5 %, indicating strong agreement with results derived from the standard method, UHPLC-MS/MS.

Wastewater remediation is a prominent concern that should be addressed, as it is a critical problem that damages natural resources and has a negative impact on living organisms. In this study, the synthesis of copper ferrite and silver doped-copper ferrite nanoparticles named CuFe₂O₄ and Ag_XCuFe₂O₄ using Monsonia burkeana (M. burkeana) as a fuel and their photocatalytic performance against the textile pollutant, Methylene blue (MB) and the pharmaceutical pollutant, sulfisoxazole (SSX) was reported. The physical, optical, spectroscopic, and surface analyses of the as-prepared nanoparticles were characterized using various techniques. XRD confirmed the crystalline structure of Ag-CuFe₂O₄ and the incorporation of silver on the surface of the nanoferrites. FTIR analysis indicated the formation of a single-phase spinel crystalline structure with two sub-lattices (T_d and O_h). UV–Vis absorption spectra of silver-substituted copper ferrite revealed that the band gap energy (E_g) decreased with increasing crystallite size. Upon testing their degradation efficiency, at pH 12, the highest degradation of 99 % after 60 min for the 7 % AgCuFe₂O₄ was reported, and the rate of the reaction was found to be 0.09769 min⁻¹. The 7 % Ag-CuFe₂O₄ catalyst could be reused more than 4 times with a minimal loss in photostability and the e⁻ and •O^2- were the primary species responsible for MB degradation. The photocatalyst 7 %Ag-CuFe₂O_4, showed a 60 % decomposition for the antibiotic after 120 min of UV-radiation. The 7 % Ag-CuFe₂O₄ photocatalyst displayed superior magnetic recovery capability under the action of the external magnetic field. These developments in this study offer wide promising applications in water environmental remediation.

This study deals with the development of a granulated Fe-pillared clay (Fe-PC) using carboxymethylcellulose (CMC) as a binder to present it as an innovative adsorbent for the individual and competitive adsorption of tetracycline (Tc) and tizanidine (Tz) from water. An optimum pH value of 7 was determined for both individual and multi-component adsorption. The optimal dosage of granulated Fe-PC was determined to be 1.5 g/L for Tz and 3 g/L for Tc, resulting in constant removal rates of 80 % for Tc and 90 % for Tz. Tizanidine showed a higher affinity for powdered or granulated Fe-PC compared to tetracycline, due to its smaller molecular size and increased amine functional groups. Consequently, Tz showed improved kinetic rates (initial pseudo-second order sorption rates of 170.79 and 25.62 mg/g.h for Tz and Tc, respectively) and equilibrium capacities (maximum monolayer adsorption capacity of granulated Fe-PC at room temperature over Tc and Tz, 54.89 mg/g and 66.40 mg/g). Granulation affected the kinetic rate for both adsorbates, albeit with a more pronounced effect for Tc. The adsorption of Tz was less sensitive to temperature changes, indicating a lower enthalpy change of adsorption (14.24 and 77.91 kJ/mol for Tz and Tc, respectively). HCl for Tc and NaCl for Tz were identified as optimal desorption eluents, confirming the involvement of cation exchange in Tz adsorption. Surface functional group analysis confirmed the proposed complexation mechanisms. Tz consistently showed a higher affinity for granular Fe-PC than Tc, especially at lower adsorbent dosages. This article provides a comprehensive insight into the characterization of the prepared adsorbents and their cyclic adsorption-desorption performance for Tc and Tz.

TiO₂ is a low-cost and biocompatible material with high oxidizing ability. However, their photocatalytic activity is limited to UV light irradiation. In this research, for the first time, a novel TiO₂/CeFeO₃ heterojunction was synthesized by the green synthesis method using an aqueous fraction of Artemisia vulgaris leaf extracts. TiO₂/CeFeO₃ shows enhanced photocatalytic performance under visible light irradiation. The vibrational, structural, optical, and compositional properties of TiO₂/CeFeO₃ were characterized. The as-prepared TiO₂/CeFeO₃ has spherical-shaped particles and shows a significantly diminished bandgap energy (3.25 eV to 2.75 eV). The photocatalytic performance of TiO₂/CeFeO₃ was investigated to degrade malachite green (MG) with an efficiency of up to 93.53% under its optimum dose. TiO₂/CeFeO₃ shows stable photocatalytic performance until the fourth cycle. The kinetics of the photodegradation of MG followed the pseudo-first-order reaction with a rate constant (k_app) of 2.14×10⁻² min⁻¹. The enhanced photocatalytic activity of TiO₂/CeFeO₃ was attributable to the creation of heterojunction, which suppresses the recombination rate of photogenerated electron-hole validated by the photoluminescence analysis. This work presents an eco-friendly approach to synthesizing novel heterojunction material with enhanced photocatalytic dye degradation.

The selective ortho–alkylation of 1–naphthol with methanol is carried out over various commercially available acid solid catalysts under relatively mild reaction conditions (<300 ºC), in batch, and anhydrous zeolite HY shows the best catalytic activity. Removal of the strongly adsorbed water in the zeolite is key for the alkylation reaction. Mechanistic studies based on isotopically labelled experiments reveal the transformation of O–methylated 1–naphthol into the desired ortho–C–methylation product after intramolecular rearrangement of the methyl group. These results open the way to design a new synthesis of ortho–methyl 1–naphthol and, consequently, of vitamin K3, based on a commercially available, inexpensive and non–toxic solid catalyst such as HY zeolite.

The Y₂O₃ decorated with ZnFe₂O₄ was successfully synthesized using Citrus limon (L.) Osbeck leaf extract for the first time. A modification of Y₂O₃ with ZnFe₂O₄ nanoparticles was carried out because Y₂O₃ is stable but has a wide band gap, making it less active in visible light. On the other hand, ZnFe₂O₄ has a small band gap and is cheap. The synthesized ZnFe₂O₄/Y₂O₃ nanocomposites, ZnFe₂O₄, and Y₂O₃ nanoparticles were characterized using FTIR, XRD, TEM, SEM, and DRS UV–Vis. TEM and DRS UV–Vis results show that the ZnFe₂O₄/Y₂O₃ nanocomposite particle has a size of 49,61 nm with a unique shape and an optical band gap of 2.08 eV. The photocatalytic activity of Y₂O₃, ZnFe₂O₄, and ZnFe₂O₄/Y₂O₃ was observed based on the photodegradation of malachite green (MG) dye under visible light. The results demonstrate that ZnFe₂O₄/Y₂O₃ can degrade MG with a photodegradation percentage of 95 % within 120 min, which is better than pure ZnFe₂O₄ and Y₂O₃. After the fourth cycle, the photodegradation percentage of MG by ZnFe₂O₄/Y₂O₃ remained at 88 %, demonstrating good reusability of ZnFe₂O₄/Y₂O₃ for photocatalytic degradation. These findings demonstrate that the use of ZnFe₂O₄ as a modifier may increase the photocatalytic performance of Y₂O₃.

The rapid development of superior, highly stable, alkaline-medium-compatible, and nonprecious earth-abundant bifunctional electrocatalysts has garnered significant research interest. This interest aims to replace the costliest noble metals (Pt, Ir/IrO₂, and Ru/RuO₂) in renewable and green energy technologies for overall water splitting. However, there are still important limitations, such as lower stability and higher energy consumption. In this work, we report the synthesis of Cu-Co metal-organic frameworks (MOFs) as a bifunctional electrocatalyst using a simple chemical precipitation technique. Especially, when 11.5 mM of Co is combined with Cu MOF, it exhibits excellent bifunctional activity for overall water splitting with a lower overpotential of 0.21 V (OER) and -0.71 V (HER) at a current density of 10 mA cm⁻², which exhibits nearly several times more enhancement than that of pristine Cu and Co MOFs in a 1 M KOH electrolyte solution. The Tafel slope value of 130 mV/dec and the lower charge transfer resistance, along with relatively high stability for up to 12 h at the onset potential of OER and HER, are observed for the 11.5 mM Cu-Co MOF electrocatalyst. The present results open an alternative pathway for developing a novel design of highly efficient and scalable bifunctional electrocatalysts for overall water splitting.