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The influence of copper addition on the structure and selected properties of AlCoCrFeNiSi0.5Cux high-entropy alloys is described. Slowly cooled ingots were prepared by induction melting, and the samples in the form of plates were obtained by pressure casting. The conducted structural studies confirmed the presence of BCC/B2 phase. Microsegregation in the ingots was associated with the formation of intermetallic Cr3Si and Fe5Si3 phases. An increase in the cooling rate stopped segregation by reducing the mobility of Cr and Si. The hyperfine magnetic field distributions indicated the formation of the BCC Fe(Co,Ni,Si,Cr) solid solution for alloys in the form of plates. The lowest corrosion-current density (0.04 μA/cm2) in 3.5%-NaCl solution was obtained for the plate with the lowest copper content. The dominated aluminum surface states for the post-corrosive plates highlighted the binding energies of Al2O3. A tendency of reduced coercivity with increased copper content was observed. The positive effect of copper addition on wear resistance was confirmed for the AlCoCrFeNiSi0.5Cu0.1 alloy. [ABSTRACT FROM AUTHOR]

Ba1.98Dy0.02SiO4 nanoceramic samples were synthesized using the most versatile sol–gel and citrate sol–gel techniques. The properties of Ba1.98Dy0.02SiO4 nanoceramics were perceived by XRD pattern, IR spectra, UV–Vis-DR Spectra, FESEM, etc. XRD confirmed the phase purity and homogeneity of the samples. Rietveld refinement methodology was employed to authenticate the prepared samples' structural parameters and crystal structure. FTIR analysis provides the IR vibrations consistent with bonding among the atoms and molecules. Compared to IR, high-frequency Raman modes attributed to SiO4 units are shifted. FESEM micrographs revealed the formation of spherical shape nanoparticles and nanorods. EDAX spectra governed the elemental composition of prepared samples, further confirmed via XPS scan. Diffuse reflectance examined optical modifications and band structure of the nanoceramics. The band gap of the proposed samples was intended to use the best relationship between the Kubelka Munk function and reflectance data. The comparative results showed that the citric acid-assisted Ba1.98Dy0.02SiO4 sample has better structural and optical characteristics with nanorod morphology functional in device fabrication. At the same time, the sample prepared by traditional sol–gel has spherical nanopowders suitable for display devices. The 0-dim and 1-dim morphology of the samples were ascribed to the significant differences in the synthesis conditions. [ABSTRACT FROM AUTHOR]

Thiol‐functionalized mesoporous silica and materials potentially dedicated to diverse applications of composite materials, metal colloids, and metal catalysts, etc. Here, we developed a new synthesis route for 3‐methacryloxypropyl trimethoxy silane (MPTMS) functionalized mesoporous silica (KIT‐6), achieving a 71.5 % enhancement in thiol functionalization on KIT‐6 surfaces. Characterization using XRD, TEM, BET, FTIR, Raman, 29Si NMR, XPS, and ICP‐OES revealed structural and morphological features. XRD, TEM, and BET confirmed the three‐dimensional structural stabilization of mesoporous silica with ~4 nm pore diameter and a surface area of 1451 m2 g−1. FTIR, Raman, and 29Si NMR studies established the mechanism of thiol functionalization, the formation of a new wormhole chain structural framework (WCSF), and stabilization through hydrogen bonding within the mesopores. The 29Si NMR spectra showed characteristic peaks (T3, T2, Q4, Q3) indicating self‐condensed functionalized thiols with siloxane networks. XPS analysis validated enhanced thiol functionalization, indicating a structurally homogeneous WCSF suitable for mercury adsorption. ICP‐OES measured a mercury adsorption capacity of 3199.6 mg g−1 for KIT‐6, with an Hg2+/S ratio of 1.8, corroborated by molecular structure and mechanism analysis. This innovative thiol functionalization approach enhances the efficacy of applications such as extracting Hg2+ from contaminated sources. [ABSTRACT FROM AUTHOR]

Chemical polishing or chemo‐mechanical polishing is crucial as a last step of surface preparation to remove the damaged layer and contaminants from the surface of CdZnTe crystals. The bromine–methanol solution is widely used for this purpose. However, bromine–methanol solution enriches the surface with Te and results in poor performance of CdZnTe crystals. In this study, the effect of the chemical polishing with 5% bromine–methanol solution on the surface and at the interface is investigated and it is demonstrated that etching duration strongly influences surface stoichiometry and interface contaminants. The evolution of the surface topography with etching and chemical changes are presented. It is shown that after 90 s etching/polishing, subsurface damage is removed and Te enrichment is minimum. Moreover, interface layer thickness is the smallest for 90 s etching duration. It is presented that further increase in the etching duration disturbs the surface stoichiometry and interface depth. It also calculated that 90 s of etching shows low interface barrier and symmetrical current–voltage curve. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The primary objective of this research paper is to explore strategies for enhancing the electrical performance of dual active layer thin film transistors (TFTs) utilizing LZTO/ZTO as the bilayer architecture. By systematically adjusting the thickness of the active layers, we achieved significant improvements in the performance of the LZTO/ZTO TFTs. An XPS analysis was performed to elucidate the impact of the varying O2 element distribution ratio within the LZTO/ZTO bilayer thin film on the TFTs performance, which was directly influenced by the modification in the active layer thickness. Furthermore, we utilized atomic force microscopy to analyze the effect of altering the active layer thickness on the surface roughness of the LZTO/ZTO bilayer film and the impact of this roughness on the TFTs electrical performance. Through the optimization of the ZTO active layer thickness, the LZTO/ZTO TFT exhibited an mobility of 10.26 cm2 V−1 s−1 and a switching current ratio of 5.7 × 107, thus highlighting the effectiveness of our approach in enhancing the electrical characteristics of the TFT device. [ABSTRACT FROM AUTHOR]

In this study, biochars were produced from by-products of the herbal industry, specifically fennel seeds (Foeniculum vulgare), through direct activation by carbon dioxide at two different temperatures. The biochar samples were comprehensively analysed. Additionally, adsorption studies were conducted for methylene blue. The resulting adsorbents exhibited a specific surface area ranging from 2.29 to 14.60 m2/g. The resulting materials displayed a basic character on their surface. The constants for adsorption models were determined for each dye as well as thermodynamic parameters and the kinetics of the process. The sorption capacities of methylene blue for the samples exhibited a range of 22 to 43 mg/g. The adsorption kinetics of the dye on the biochar materials were found to follow a pseudo-second-order model, with the adsorption process best described by the Langmuir isotherm for the DA-800 sample and the Freundlich isotherm for the DA-750 sample. This indicates the development of a monolayer adsorbate on the biochar surfaces. The efficacy of the adsorption process in aqueous solutions of methylene blue was found to increase with rising temperature. Furthermore, based on thermodynamic studies, the adsorption process was found to be spontaneous and endothermic. [ABSTRACT FROM AUTHOR]

Lithium iron phosphate (LiFePO4 or LFP) is a promising cathode material for lithium-ion batteries (LIBs), but side reactions between the electrolyte and the LFP electrode can degrade battery performance. This study introduces an innovative coating strategy, using atomic layer deposition (ALD) to apply a thin (5 nm and 10 nm) Al2O3 layer onto high-mass loading LFP electrodes. Galvanostatic charge–discharge cycling and electrochemical impedance spectroscopy (EIS) were used to assess the electrochemical performance of coated and uncoated LFP electrodes. The results show that Al2O3 coatings enhance the cycling performance at room temperature (RT) and 40 °C by suppressing side reactions and stabilizing the cathode–electrolyte interface (CEI). The coated LFP retained 67% of its capacity after 100 cycles at 1C and RT, compared to 57% for the uncoated sample. Post-mortem analyses, including scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), were conducted to investigate the mechanisms behind the improved performance. These analyses reveal that Al2O3 coatings are highly effective in reducing LFP electrode degradation during cycling, demonstrating the potential of ALD Al2O3 coatings to enhance the durability and performance of LFP electrodes in LIBs. [ABSTRACT FROM AUTHOR]

This study analyzes the influence of different ultrasonic amplitudes on the microstructure composition, microhardness, tensile strength, and corrosion resistance of Al alloy/steel laser welding-brazing joints assisted by ultrasonic vibration. The application of ultrasonic vibration did not change the microstructure composition of the joints but refined them. The joints were all composed of θ-Fe(Al, Si)3 and τ5-Al7.2Fe1.8Si formed at the interface reaction zone, as well as an α-Al solid solution and Al-Si eutectic phase generated in the weld seam zone. Meanwhile, the thickness of the IMCs at the interface decreased with an increase in the ultrasonic amplitude. When the ultrasonic amplitude was 8 μm, the IMCs thickness was a minimum of 1.62 μm. In this condition, the reduction of the IMCs thickness and the refined grain of joints made the microhardness and tensile strength reach the maximum. The fracture of joints with ultrasonic amplitudes of 0 and 4.8 μm began at the weld seam and extended to the interface reaction zone at the steel side, while the fracture of joints was located in the heat-affected zone (HAZ) of the Al alloy side when the ultrasonic amplitude was 8.0 and 11.2 μm. The fracture mode of the former presented a typical mixed fracture with cleavage steps and tearing edges, and that of the latter showed ductile fracture with uniform and fine ductile dimples. The corrosion resistance of the joints was improved by adding ultrasonic vibration. When the ultrasonic amplitude was 8 μm, its corrosion resistance was optimum; it was ascribed to a dense oxide film formed on the surface of the metal under the action of ultrasonic vibration. [ABSTRACT FROM AUTHOR]

The hydrothermal preparation of catalytic NiPd x Co 2-x O 4 (x ≦ 0.08) nano-electrocatalysts on Ni foam (NF) was successfully accomplished. The morphology and chemical composition of the catalysts are confirmed by advanced analytical techniques XRD, SEM, EDX, TEM, HR-TEM, and XPS. The NiPd x Co 2-x O 4 (x = 0.06) NF nano-electrocatalyst demonstrated remarkable performance in the HER, with an overpotential of 191.6 mV, a Tafel slope of 84.7 mV/dec, and extraordinary stability over 24 h using chronopotentiometry methods. The surface and electrochemical analyses demonstrated that the sample, doping with a 6.0% Pd2+ concentration, had appreciably enhanced performance in the HER. The improvement may be attributed to a much larger electrochemical surface area and fast charge transfer kinetics at the semiconductor and electrolyte interface. The influence of Pd dopants on the HER performance of CNs is studied with the help of density functional theory. It elucidates the way in which hydrogen and water molecules bind to the surface of PCN slabs. The theoretical results suggest that the incorporation of Pd dopants enhances the electrocatalytic process and boosts the HER activity as the concentration of Pd increases. The density of state spectra reveals their effect on spin-dependent electronic structure characteristics. Our findings point to a practical path for creating distinctive electrocatalysts that will serve as better electrodes for a variety of forthcoming hydrogen fuel cell applications. • NiPd x Co 2-x O 4 (0.00 ≥ x ≦ 0.08) nano - electrocatalyst on Ni foam (NF) were synthesized successfully first time. • Pd doping concentration into NiPd x Co 2-x O 4 crystal structure enhanced the active sites tremendously. • The NiPd x Co 2-x O 4 (x = 0.06) electrocatalyst demonstrated remarkable performance in the HER. • Overpotential of 180.9 mV, a Tafel slope of 84.7 mV/dec mV at 10 mA cm-2, exceptional stability for 1000 cycles. • DFT for exploring and explaining the effect of Pd dopants on the catalytic and HER activity is elucidated. [ABSTRACT FROM AUTHOR]

Manganese co-precipitated with goethite (Mn-FeOOH) is ubiquitous within (sub-)surface environments, which are considered one of the most important sinks for phosphorus pollution management. Accordingly, various mole ratios of Mn-FeOOHs are synthesized and characterized by XRD, FE-SEM, FTIR, BET, XPS, hysteresis loop, acid–base titration and zero potential. According to XRD and FESEM images, the substitution of Mn causes subtle alterations in the microstructure and crystal structure of goethite, and the morphology of Mn-FeOOHs is transformed from needle-shaped goethite to a short-rod-shaped rough surface with increasing Mn substitution. Based on the analysis of BET and acid–base titration, the substitution of Mn into goethite significantly improved the surface area, pore volume, surface properties and active sites of goethite, thereby establishing a theoretical basis for effective subsequent adsorption. Batch experiment results show that the removal rate of phosphate decreases with the increasing solution pH, indicating that acidic groundwater conditions are more conducive to the removal of phosphate. In addition, the adsorption of phosphate on Mn-FeOOHs is independent of ionic strength, indicating that the inner-sphere surface complexation predominated their adsorption behaviors. The isotherm experiment results showed that Mn-G15 exhibits the strongest adsorption capacity for phosphate at pH 5.5 and T = 318 K, with a maximum adsorption capacity of 87.18 mg/g. These findings highlighted the effect of Mn content on the fixation of phosphate onto Mn-FeOOHs from (sub-)surface environments in pollution management. [ABSTRACT FROM AUTHOR]

In the gas treatment center in smelters, hydrogen fluoride (HF) is separated from the outlet gases of electrolysis cells, which are used to produce aluminum from alumina. However, SO2 largely remains in the effluent gas. Another method has to be developed to separate this gas which is harmful to the environment. In this study, semi-dry desulfurization of a SO2 containing gas was performed at low SO2 concentrations using hydrated lime [Ca(OH)2] as a catalytic desulfurizer under specific humidity conditions. The low reaction temperature of 100 °C and minimal use of the Ca-based desulfurizer under 17 % relative humidity achieved more than 95 % removal of SO2. The morphological changes and presence of sulfur in different lime samples were analyzed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Brunauer–Emmett–Teller (BET) analysis showed changes in the surface properties of hydrated lime after desulfurization. X-ray photoelectron spectroscopy (XPS) analysis provided the phase and composition identification of the sulfur species on hydrated lime and the CaSO3/CaSO4 product ratio. Based on the experimental results, the optimum catalyst surface area with a specific particle size is critical to the effective conversion of Ca(OH)2 into CaSO3 and CaSO4. The practicality of a Ca-based desulfurizer and its ability to convert into the required product may be the key to reducing the overall cost of desulfurization in aluminum industry.

Recent research work revealed that Ni43.9Co22.4Fe8.8Al10.7Ti11.7B2.5 HEA is one of the ultra-high strength and ductile superlattice alloys. In this work, high-temperature oxidation behavior of the as-cast Ni43.9Co22.4Fe8.8Al10.7Ti11.7B2.5 alloy was investigated at 1000 ℃ up to 100 h. The oxidized samples were characterized using X-ray Diffractometer, Energy Dispersive Spectroscopy, and X-ray Photoelectron Spectroscopy. The results revealed that the initial microstructure of the alloy consists of face centered cubic (FCC) and L12 structures. High-temperature exposure resulted in the formation of Al2O3 and TiO2 scales during the initial hours of oxidation, which eventually spall-off after 25 h of exposure allowing further oxidation. The results showed that protective oxide layers such as Al2O3 and TiO2 were not present after 100 h of exposure. The external layer of the 100 h oxidized sample was composed of Fe, Co, and Ni-rich oxides which are known to have mere effective resistance against oxygen ingression. The alloy which has superior strength and ductility may be used for high temperature applications after attaining the thermally stable fine-grain microstructure by suitable thermomechanical processing / providing oxidation resistance coating / by doping with elements having superior oxidation resistance.

We report on the XPS analysis of degraded surfaces inside San Pietro Barisano, the rupestrian church carved into the calcarenite rock of ancient Matera, which has been a UNESCO World Heritage Site since 1993. As reported in previous works, the "Sassi" district and the park of rupestrian churches were available as open laboratories for the National Smart Cities SCN_00520 research project dedicated to the sustainable recovery of this remarkable architectural heritage. In that context, XPS functionality was shown to reside in the possibility of analyzing surfaces by feasible sampling, acquiring spectra without any preliminary sample treatment, and processing data using a well-established curve fitting procedure. The obtained results allowed us to identify the degradation products of the investigated surfaces, thus contributing to defining a diagnostic framework for subsequent actions. Accordingly, the samples here considered, collected from the internal wall surfaces of the church, were all analyzed in comparison with the reference calcarenite, and the XPS results were evaluated as a function of local environmental factors and the historical context of the church itself. The final aim was to provide, for each sample, the most representative indicator(s) of biotic and/or abiotic degradation for reliable use, in a multidisciplinary context, in planning care interventions for building heritage. [ABSTRACT FROM AUTHOR]

In recent years, there has been growing demand for processes to form electromagnetic shielding films on the periphery of semiconductor packages, and shielding films are increasingly being formed by sputter deposition methods with stable processes. However, little consideration has been given to the adhesion mechanism between the mold resin and sputtered Cu film formed on the semiconductor devices. In this study, Cu films were sputtered on mold resin with different etching conditions, and X-ray photoelectron spectroscopy was used to analyze the state of the interface, which affects adhesion. The color difference of the mold resin surface under different Ar and N2 etching conditions was also evaluated. Excellent adhesion between the mold resin and sputtered Cu was achieved under a high flow rate for Ar + N2 etching. The amount of Si (SiO2) exposed on the mold resin surface was correlated with the color difference. We proposed a mechanism in which amino groups in particular were formed on the surface of the mold resin, the resin etching rate increased, and the amount of SiO2 exposed increased. Functional groups, especially amino groups, were also formed on the SiO2 surface by N2 plasma. Cuσ+ in the sputtered film and Nσ- formed on the SiO2 surface adhered to each other through polar interactions. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The primary objective of this research paper is to explore strategies for enhancing the electrical performance of dual active layer thin film transistors (TFTs) utilizing LZTO/ZTO as the bilayer architecture. By systematically adjusting the thickness of the active layers, we achieved significant improvements in the performance of the LZTO/ZTO TFTs. An XPS analysis was performed to elucidate the impact of the varying O2 element distribution ratio within the LZTO/ZTO bilayer thin film on the TFTs performance, which was directly influenced by the modification in the active layer thickness. Furthermore, we utilized atomic force microscopy to analyze the effect of altering the active layer thickness on the surface roughness of the LZTO/ZTO bilayer film and the impact of this roughness on the TFTs electrical performance. Through the optimization of the ZTO active layer thickness, the LZTO/ZTO TFT exhibited an mobility of 10.26 cm2 V−1 s−1 and a switching current ratio of 5.7 × 107, thus highlighting the effectiveness of our approach in enhancing the electrical characteristics of the TFT device.

Lithium iron phosphate (LiFePO4 or LFP) is a promising cathode material for lithium-ion batteries (LIBs), but side reactions between the electrolyte and the LFP electrode can degrade battery performance. This study introduces an innovative coating strategy, using atomic layer deposition (ALD) to apply a thin (5 nm and 10 nm) Al2O3 layer onto high-mass loading LFP electrodes. Galvanostatic charge–discharge cycling and electrochemical impedance spectroscopy (EIS) were used to assess the electrochemical performance of coated and uncoated LFP electrodes. The results show that Al2O3 coatings enhance the cycling performance at room temperature (RT) and 40 °C by suppressing side reactions and stabilizing the cathode–electrolyte interface (CEI). The coated LFP retained 67% of its capacity after 100 cycles at 1C and RT, compared to 57% for the uncoated sample. Post-mortem analyses, including scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), were conducted to investigate the mechanisms behind the improved performance. These analyses reveal that Al2O3 coatings are highly effective in reducing LFP electrode degradation during cycling, demonstrating the potential of ALD Al2O3 coatings to enhance the durability and performance of LFP electrodes in LIBs.

Due to their versatile and unique properties, tantalum-based thin films have been extensively studied. However, tantalum is susceptible to oxidation due to its higher chemical activity, which is crucial regardless of whether oxidations of Ta are beneficial or detrimental. Therefore, the oxidation of Ta during material processing, especially without conscious means, should be taken seriously. In this study, pure Ta films were fabricated by magnetron sputtering under set procedure parameters. The effects of base pressure and substrate temperature on the degree of oxidation of Ta films were investigated. The results revealed that the magnitude of the base pressure directly affects the oxidation state of the as-deposited Ta films. When preferably avoiding the oxidation of sputtered Ta films, the base pressure should be controlled below 4.4 × 10−4 Pa. The substrate temperature has little effect on the oxidation state of the as-deposited Ta films under a base pressure ranging from about 10−2 Pa to 10−4. We hope that this study can provide some references for controlling the oxidation states of Ta involved in relevant film preparation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the study of the influence of argon/nitrogen gas concentration ratio in the of reactive magnetron sputtering process on the formation of titanium nitride (TiN) thin films. The addition of 5% nitrogen to the gas mixture is sufficient for the formation of titanium nitride films. It was found that changing the concentration of nitrogen in the reactive gas mixture affects the morphology of the surface, in particular, increasing the concentration of nitrogen leads to an increase in surface roughness of the resulting TiN films. According to the results of Raman spectroscopy, there is a dependence of the ratio of peak areas (TO + LO)/(TA + LA) observed in the regions of 603, 175 and 315 cm-1, respectively, on the N2 concentration. The X-ray Photoelectron Spectroscopy (XPS) analysis results show that increasing the nitrogen content in the reactive gas leads to a decrease in the oxygen concentration in the thin films. The results deepen the understanding of the synthesis of TiN thin films and their potential for the development and improvement of materials for various applications including microelectronics, optics, and coatings. [ABSTRACT FROM AUTHOR]

The sepiolite/ZrO2 composites were prepared by sepiolite (Sep) modification with zirconium propoxide in toluene at room temperature for 24 h (Sep–ZrI) or 95 °C for 4 h (sample Sep–ZrII). The efficiency of the obtained composites for the removal of phosphate from aqueous solutions at initial pH = 4 and pH = 8 was investigated. Characterization of the samples shows that synthesis at a higher temperature for a shorter time provides a slightly higher content of amorphous Zr phase, which is deposited on the sepiolite fibers as a thin layer and agglomerated nanoparticles. Compared to Sep, the composites have a lower point of zero charge and higher specific surface area and pore volume. The adsorption kinetics follow the pseudo second-order model. The adsorption capacities of the composites are approximately the same at both initial pH and higher at initial pH = 4 than at pH = 8. The XPS and ATR-FTIR of Sep–ZrI before and after adsorption identifies the formation of inner-sphere complexes as the mechanism of phosphate adsorption. The slow release during desorption with NaOH solution confirms the strong bonds of the phosphates with the surface of the composites. [ABSTRACT FROM AUTHOR]

Chitosan hydrogels are biomaterials with excellent potential for biomedical applications. In this study, chitosan hydrogels were prepared at different concentrations and molecular weights by freeze-drying. The chitosan sponges were physically crosslinked using sodium bicarbonate as a crosslinking agent. The X-ray spectroscopy (XPS and XRD diffraction), equilibrium water content, microstructural morphology (confocal microscopy), rheological properties (temperature sweep test), and cytotoxicity of the chitosan hydrogels (MTT assay) were investigated. XPS analysis confirmed that the chitosan hydrogels obtained were physically crosslinked using sodium bicarbonate. The chitosan samples displayed a semi-crystalline nature and a highly porous structure with mean pore size between 115.7 ± 20.5 and 156.3 ± 21.8 µm. In addition, the chitosan hydrogels exhibited high water absorption, showing equilibrium water content values from 23 to 30 times their mass in PBS buffer and high thermal stability from 5 to 60 °C. Also, chitosan hydrogels were non-cytotoxic, obtaining cell viability values ≥ 100% for the HT29 cells. Thus, physically crosslinked chitosan hydrogels can be great candidates as biomaterials for biomedical applications. [ABSTRACT FROM AUTHOR]

A poly(thiophene acetic acid)/Au/poly(methylene blue) nanostructured interface was electrochemically assembled step-by-step on screen-printed carbon electrodes (SPCE) for label-free detection of p53 protein. The initial electrical conductive properties of the polymeric interface were increased with an additional layer of poly(methylene blue) electropolymerized in the presence of gold nanoparticles. The nano-immunosensing architecture was prepared by covalent immobilization of anti-p53 antibodies as bioreceptors through the poly(thiophene acetic acid) moieties. The nano-immunosensor assembly was extensively characterized by ultraviolet–visible spectrophotometry, dynamic and electrophoretic light scattering, scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, atomic force microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Under optimal conditions, p53 was specifically and selectively detected by square wave voltammetry in a linear range between 1 and 100 ng mL−1 with a limit of detection of 0.65 ng mL−1. In addition, the electrochemical nano-immunosensor detected p53 in spiked human serum samples and colorectal cancer cell lysates, and the results were validated with a standard spectrophotometric method using a paired samples t test, which did not exhibit significant differences between both methods. The resultant p53 nano-immunosensor is simple to assemble, robust, and has the potential for point-of-care biomarker detection applications. [ABSTRACT FROM AUTHOR]

In order to explore the effect of ZrH2 on the electron emission performance of rare earth tungsten electrodes (W-La-Y), different proportions of ZrH2 were added to rare earth tungsten in this study, and samples of three proportions were obtained by ball milling and vacuum hot-pressing sintering. The electron emission performance, phase evolution and surface valence state of the samples were analyzed, respectively. The test results of electrode emission performance show that increasing the mass fraction of ZrH2 in the range of 0% to 0.1% can continuously improve the electrode emission performance. At 1600 °C, 0.1% ZrH2 can increase the zero-field current emission density from 0.36 to 0.90 A/cm2. X-ray diffraction (XRD), the comprehensive thermalgravimetric and differential thermal analysis (TG-DTA) and X-ray photoelectron spectroscopy (XPS) results showed that the ZH2 added to rare earth tungsten electrodes would react with impurity oxygen in the electrode and consume impurity oxygen, thus reducing the inhibitory effect of impurity oxygen on the electron emission of the electrode and improving its electron emission performance. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are one of the most promising precursors for the fabrication of advanced photocatalysts. In this report, we present a stable in water MOF based on earth-abundant cobalt (Co-BDC) as a highly active catalyst for visible-light-driven H 2 generation. The rate of H 2 production sensitized by eosin Y (EY) over Co-BDC reached 14.5 mmol g−1 h−1. By in situ addition of graphene oxide suspension to the photocatalytic system, the hydrogen production efficiency was further enhanced by a factor of 6.6. Boosting photocatalytic hydrogen generation by integrating Co-MOF and graphene oxide. [Display omitted] • Boosting photocatalytic hydrogen generation by integrating Co-MOF and graphene oxide. • Design of water stable Co-MOF as an efficient catalyst for light-driven hydrogen generation. • Photoactive water stable Co-MOF as intrinsic catalyst for hydrogen generation. • Enhanced photocatalytic hydrogen evolution by combining water stable Co-MOF with graphene oxide. [ABSTRACT FROM AUTHOR]

This work studies two copper-based alloys as potential antimicrobial weapons for sectors where surface hygiene is essential. Effects of different alloying elements addition at the same Cu content (92.5% by weight) on the corrosion resistance and the antibacterial performance of two copper alloys were studied in an aerated disinfectant solution (0.25% v/v Aniosurf Premium (D)) by electrochemical corrosion, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS) and antibacterial tests. Results showed that the nature of the alloying elements had a clear influence on the corrosion resistance and antibacterial performance. Electrochemical impedance results and surface analyses demonstrate the presence of organic compounds bound on the substrate and that a film covers part of the total active surface and may act as a protective barrier by preventing the interaction between metal and solution, decreasing the antimicrobial performance of copper-based materials. Low zinc and silicon contents in copper alloys allows for better aging behavior in D solution while maintaining good antibacterial performance. The XPS and ToF-SIMS results indicated that artificial aging in disinfectant enhanced Cu enrichment in the organic film formed, which could effectively stimulate the release of Cu ions from the surface. [ABSTRACT FROM AUTHOR]

We have developed a novel set of (Mn3O4 and/or MnxNi1-xO)/NiO heterostructured nanocrystals (HNCs) that show promise for multifunctionality. A two-step procedure was used to synthesize our HNC samples. Thermal decomposition was used first to synthesize NiO core nanoparticles, while hydrothermal synthesis under varying pH conditions was then used to produce overgrowth of a MnxNi1-xO shell and/or Mn3O4 islands on the NiO core. In this work, we report on the investigation of the defects and surface/interface chemistry of our HNC samples using x-ray photoelectron spectroscopy (XPS). The results from a detailed analysis of the Mn 2p XPS spectra show that the Mn3+:Mn2+ ratio increases with the increasing pH value used in synthesis of the samples. This is consistent with a trend toward a predominance of Mn3O4 islands at higher pH values, a predominance of MnxNi1-xO shell at the lowest pH values, and a mixture of both for intermediate pH values. A reduction of the satellite features of the Ni 2p XPS with increasing pH of the synthesis medium is attributed predominantly to surface/interface defects of the HNCs. Fitting of the O 1 s XPS spectra shows that Ni-OH and Mn-OH are likely the dominant contributions to the lateral peak, whereas defects such as oxygen in an oxygen-deficient environment and/or oxygen vacancies comprise a smaller contribution. Analysis of both the Ni 2p and O 1 s XPS measured from our samples only shows evidence for a Ni2+ chemical environment (i.e., negligible Ni3+) in octahedral coordination, consistent with a rocksalt structure and well-ordered NiO or MnxNi1-xO nanomaterial. The presence of point defects and the nature of the surface/interface chemistry as determined using XPS suggests that our HNC samples may also be suitable for heterogeneous catalysis applications. [ABSTRACT FROM AUTHOR]

• Synthesized ZnO powders have a crystalline structure and belong to the group of hexagonal symmetry, of the wurtzite type. • In the ZnO powder, there are no reflections that would indicate any impurities or remaining unreacted amounts of reagents. • Increasing the synthesis temperature leads to the growth of ZnO nanoparticles from 15-30 nm at 25°C to 40-50 nm at 60°C. • The synthesis temperature affects the shape of ZnO nanoparticles, which are needle-like at 25°C and flower-like at 60°C. This study examines the synthesis of ZnO powder via the sol–gel method at temperatures of 25 °C and 60 °C. Characterization was conducted using standard techniques to investigate how these temperature conditions influence the physicochemical properties of the resulting material. XRD analysis confirmed high crystallinity with a pure hexagonal wurtzite structure, with average crystallite sizes of approximately 20 nm at 25 °C and 38 nm at 60 °C. Both SEM and TEM techniques established needle-like nanorods at 25 °C and nanoflower-like structures at 60 °C. Analyzing the high-resolution XPS spectra of the Zn2p and O1s photoelectron lines revealed a predominant Zn(II) state, with the contribution of ZnO increasing from 14.6 at.% to 41.6 at.% at higher temperatures. This change was accompanied by a decrease in defective oxygen and water content. Furthermore, DSC analysis revealed significant differences in thermal properties of ZnO powders synthesized at 25 °C and 60 °C, with distinct endothermic peaks around 120 °C corresponding to the evaporation of the solvent used in the synthesis process. The energy required for phase transitions was notably higher for the 25 °C synthesis, indicating greater thermal stability and energy demands compared to the 60 °C synthesis. [ABSTRACT FROM AUTHOR]

Zirconium phosphate (ZrP) recently introduced in intumescent fire protective coating has shown improvement in developing ceramic layer. The tubular halloysite clay (THC) due to its unique molecular structure can be combined with ZrP to enhance fire resistance by developing a strong silica network on the char surface. This study is aimed to investigate the synergistic effects of tubular halloysite clay and zirconium phosphate fillers to improve the thermal performance of the intumescent coating. The control coating formulation and a range of coating formulations using a combination of weight percentage of THC and ZrP were developed to study the influences of fillers on fire performance. The char expansion and fire resistance tests of the coatings were conducted using furnace fire test and Lab scale fire jet. Thermal stability of the coating was determined by TGA and char was characterized by FESEM, XRD, FTIR and XPS. Water-resistance test of the coating was performed according to ASTM D-870. Results showed that the reinforcement of THC-ZrP showed promising improvement on the performance of IFC and substrate temperature was far below the critical temperature, 550 °C. Sample HZ 5 showed the least backside steel substrate temperature of 219 °C. Expansion rate of char was found reduced with the addition of THC but improved the char compactness. The addition of THC and ZrP in IFC improved 18% fire resistance performance and 5% residual wt. Of char. Char morphology showed silica network, XRD and FTIR confirmed the presence of silicon. Water absorption test showed 95% less water absorption (HZ-5) compared to control coating. Post water immersion, fire test showed 7% increase in substrate temperature which is 18% less than control coating after water immersion fire test.

• La 1-x Sr x Co 1-y Fe y O 3 perovskite-type oxides are renowned for their remarkable mixed ionic-electronic conductivity. • We synthesized single-phase La 0.5 Sr 0.5 Co 0.8 Fe 0.2-x Al x O 3-δ (x = 0–0.20) perovskite oxides via solution combustion. • Introducing trivalent aluminum (Al3+) into perovskite B-site enhanced redox stability and mitigated oxygen variations. • Al-substitution significantly influenced surface morphology, oxygen nonstoichiometry, and electrical conductivity. • Oxygen nonstoichiometry significantly influenced oxygen transport parameters, resulting in improved D chem and K chem at 900 °C for these perovskites. In recent years, there has been a surge in the investigation of perovskite-type complex oxides, with a particular focus on La 1-x Sr x Co 1-y Fe y O 3 , renowned for their exceptional mixed ionic-electronic conducting (MIEC) properties. La 0.6 Sr 0.4 Co 1-y Fe y O 3 compositions have prominently emerged in this research domain. The hypothesis of enhancing redox stability and mitigating oxygen variations by incorporating trivalent aluminum (Al3+) into the B-site of perovskite structures has gained attention. In this study, single-phase La 0.5 Sr 0.5 Co 0.8 Fe 0.2-x Al x O 3-δ (x = 0–0.20) perovskite oxides were synthesized using the solution combustion technique. The physicochemical properties of the synthesized materials were thoroughly characterized, including their morphology, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) analysis, oxygen nonstoichiometry, and electrical transport properties. Results revealed lattice parameter variations associated with oxygen nonstoichiometry and B-site cation size, exhibiting a decline up to x = 0.10 followed by an increase. Al-substitution significantly influenced surface morphology, oxygen nonstoichiometry, and electrical conductivity. Notably, La 0.5 Sr 0.5 Co 0.8 Fe 0.1 Al 0.1 O 3-δ displayed lower electrical conductivity (676 S cm−1 at 300 °C) among the studied oxides. Oxygen nonstoichiometry had a significant impact on oxygen transport parameters, with these perovskites demonstrating improved chemical diffusion coefficient, D chem (5.5 × 10-5 cm2 s−1), and the oxygen surface exchange coefficient, K chem (2.32 × 10-5 cm s−1) at 900 °C, suggesting its potential as an oxygen transport membrane. These findings underscore the promising role of Al-substituted perovskite oxides in various advanced applications. [ABSTRACT FROM AUTHOR]

Here Pr3+ was introduced in the Sr2+ site in Sr 1-x Pr x TiO 3 (x = 0.05, 0.075, 0.10, 0.125, 0.15, 0.20) system followed by two step graphite burial sintering. Powder reduction helps to increase the carrier concentration and the doped sample pellet reduction minimizes Double Schottky Barrier generated by strontium and oxygen vacancies at grain boundary by regulating the point defects. Samples with x ≥ 0.10 shows splitting and asymmetry of (200) and (310) peak in XRD indicating structural transformation from cubic to tetragonal phase. XPS spectra of the samples confirmed the formation of oxygen vacancies and reduction of Ti4+ to Ti3+ induced by graphite burial sintering resulting in enhanced carrier concentration. A maximum power factor of 1.8 mW/mK2 was obtained for Sr 0.9 Pr 0.1 TiO 3 samples at 673 K. Reduced thermal conductivity due to porous structure, Pr defect centers, oxygen vacancy clusters together with enhanced power factor lead to a maximum figure of merit 0.33, making this an ideal candidate as n type legs in thermoelectric generators. [Display omitted] • The cubic symmetry of Sr 1-x Pr x TiO 3 was broken by and transformed it to Tetragonal system. • Double Schottky Barrier, inhibiting TE performance was eliminated with the two step graphite reduction. • A maximum TE power factor of 1.8 mW/mK2 is achieved for x = 0.10. • Porous structure, Pr defect centers, Oxygen vacancies along with reduced thermal conductivity lead to maximum ZT of 0.33. [ABSTRACT FROM AUTHOR]

Despite the promises in high‐energy‐density batteries, Li‐metal anodes (LMAs) have suffered from extensive electrolyte decomposition and unlimited volume expansion owing to thick, porous layer buildup during cycling. It mainly originates from a ceaseless reiteration of the formation and collapse of solid‐electrolyte interphase (SEI). This study reveals the structural and chemical evolutions of the reacted Li layer after different cycles and investigates its detrimental effects on the cycling stability under practical conditions. Instead of the immediately deactivated top surface of the reacted Li layer, the chemical nature underneath the reacted Li layer can be an important indicator of the electrolyte compositional changes. It is found that cycling of LMAs with a lean electrolyte (≈3 g Ah−1) causes fast depletion of salt anions, leading to the dynamic evolution of the reacted Li layer structure and composition. Increasing the salt‐solvent complex while reducing the non‐solvating diluent retards the rate of depletion in a localized high‐concentration electrolyte, thereby demonstrating prolonged cycling of Li||NMC622 cells without compromising the Li Coulombic efficiencies and high‐voltage stability. [ABSTRACT FROM AUTHOR]

The unique semiconductor and optical properties of copper oxides have attracted researchers for decades. However, using fruit waste materials such as peels to synthesize the nanoparticles of copper oxide (CuO NPs) has been rarely described in literature reviews. The main purpose of this part of the research was to report on the CuO NPs with the help of apple peel extract under microwave irradiation. Metal salts and extracts were irradiated at 540 W for 5 min in a microwave in a 1:2 ratio. The crystallinity of the NPs was confirmed by the XRD patterns and the crystallite size of the NPs was found to be 41.6 nm. Elemental mapping of NPs showed homogeneous distributions of Cu and O. The NPs were found to contain Cu and O by EDX and XPS analysis. In a test involving two human pathogenic microbes, NPs showed antibacterial activity and the results revealed that the zone of inhibition grew significantly with respect to the concentration of CuO NPs. In a biofilm, more specifically, NPs at 25.0 µg/mL reduced mean thickness and biomass values of S. aureus and E. coli biofilms by >85.0 and 65.0%, respectively, with respect to untreated controls. In addition, environmentally benign materials offer a number of benefits for pharmaceuticals and other biomedical applications as they are eco-friendly and compatible. [ABSTRACT FROM AUTHOR]

This study investigated the corrosion behavior of AISI 316L produced by direct energy deposition (DED). Microstructural and chemical analysis showed a homogeneous distribution of Si and Si–Mn inclusions of 0.5–1 µm and the Cr and Mo enrichment within interdendritic areas. Scanning Kelvin probe analysis of additively manufactured stainless steel highlighted a regular "striped‐like" surface potential feature with a potential gradient of 30 mV for a mean value of 0.320 ± 0.017 V versus standard hydrogen electrode. It can be related to the presence of the residual stress in the oxide film and the complex thermal history due to the fabrication process. A cyclic corrosion test simulating atmospheric conditions revealed the same corrosion properties for stainless steel fabricated by DED compared to cold rolled one. Various surface preparations of 316L were also exposed for corrosion tests. It was found that the "as‐received" and "brushed" surfaces exhibited poorer corrosion resistance due to the presence of an as‐build defective layer. However, prior passivation of brushed surface, machining, or mechanical grinding down to P1200 improve significantly the corrosion resistance. [ABSTRACT FROM AUTHOR]

The corrosion behavior of a Ti6321 weldment was investigated for the first-time ever in a deep sea environment with low temperature and low dissolved oxygen content. Electrochemical test results indicated that the corrosion resistance of the weldment deteriorated significantly in the deep seawater. This was especially true for the heat affected zone, which provided initial sites for pitting corrosion. The results of x-ray photoelectron spectroscopy measurements revealed that the corrosion film in the deep sea was less oxidized (the oxygen content of the deep-sea weldment was 10%–17% lower than that of the shallow-sea weldment). This can be attributed to the low dissolved oxygen content and the low temperature in the deep sea environment, which led to an increase in the defect density of the corrosion film on the surface. Consequently, deterioration in the anti-corrosion properties of the weldment was observed. [ABSTRACT FROM AUTHOR]

High amylose and waxy starches from maize and potato were incubated with plasma-activated water (PAW) at 25 °C, 60 °C, and 80 °C temperatures to investigate PAW treatment effects on the starches' properties. At 60 °C incubation temperature, the starches were basically annealed with PAW. Annealing starches with PAW significantly increased (p