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High density, skin effect, and environmental instability are significant limitations that restrict the application of metal-based microwave absorbers in achieving lightweight, high performance, and long service life. This study broke from traditional methods for preparing a microwave absorber Mn 2 O 3 -Fe 3 O 4 @PPy (polypyrrole) by employing an innovative annealing process to convert metal into metal oxide by the introduction of metal organic framework (MOF), which effectively achieving a more lightweight absorber material with hollow porous nanocube structure. Subsequently, PPy was coated onto the metal oxide surface to form a core-shell structure by a situ chemical oxidation synthesis method. The combination of metal oxide of the hollow porous nanocube structure and the core-shell structure formed by highly conductive PPy shell significantly enhanced heterogeneous interfaces and electromagnetic (EM) wave reflection. Excellent dielectric loss and impedance matching contributed evidently to the ultra-wideband EM wave absorption performance. It was demonstrated that, with a filling amount of only 20 wt%, the prepared Mn 2 O 3 -Fe 3 O 4 @PPy achieved an effective bandwidth (EAB) of 10.0 GHz at a thickness of 3.08 mm, with EAB max reaching 13 GHz. At a filling amount of only 10 wt%, the reflection loss (RL) was −62.13 dB, achieving an EAB of 7.4 GHz at 2.98 mm thickness, with EAB max reaching 11.4 GHz. Furthermore, the proposed strategy incorporating metal oxide and PPy enhanced corrosion resistance with higher charge transfer resistance. The ultra-wideband microwave absorption material uses an innovative annealing process for MOF, and then ingenious combines with the coated PPy to form a hollow porous nanocube core-shell structure. Excellent microwave absorption performance: EAB max = 13 GHz, RL min = −62.13 dB, low fill of 10 wt%. In addition, the corrosion resistance of the metal is improved. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present research, it is reported that ball milling technique can be applied to enhance the photocatalytic properties of MnO and ZrO 2 metal oxide powders (MZOx) furthermore the fabricated photocatalyst can be used for the degradation of tetracycline (TTC). XRD analyses revealed that increasing the milling time resulted in the formation of a pure metallic Mn crystal phase, which boosted the antibiotic degradation rate. It was confirmed by SEM technique that the morphological structures of the particles were generally small and uniform. The band gap energy was calculated as 3.70 eV for the hybrid metal oxide. Additionally, the adsorptive and photoluminescence features were illuminated via DRS and PL analyses. The effect of milling time had a major impact on the photodegradation rate of TTC, and the 8 h milling sample (MZOx-8h) exhibited the highest catalytic degradation activity (79.4 %). Low photocatalytic activity was obtained at acidic pHs and increased at alkaline pHs. The presence of H 2 O 2 sharply decreased photocatalytic process time (60 min) and 94.3 % of the TTC was degraded at 7.5 mM H 2 O 2. The photocatalytic degradation process proceeded through superoxide radicals and was supported by holes. The stability of MZOx-8h almost remained constant (70.02 %) even after seven cycles. It was determined that the presence of oxalic acid positively affected the progress of TTC degradation reactions. Further, practical application areas were investigated and MZOx-8h doped on support materials was found to be suitable for such applications in proportion to the doping ratio. Finally, it was demonstrated that MZOx-8h exhibited remarkable performance in photocatalytic reactions of different types of organic pollutants. The synergistic nature of MnO and ZrO 2 with the contribution of ball milling time effect resulted in high photocatalytic activity. • High purity metallic Mn phase was successfully synthesized by ball-milling. • MZOx was used for the first time in TTC photodegradation. • TTC degradation was stable in the seventh cycle. • The different organic pollutants were removed with high efficiency. [ABSTRACT FROM AUTHOR]

A comparative study of the Gd2O3:Tb and Y2O3:Tb nanoparticles (NPs) was presented to examine the influence of the host lattices on the crystallographic phase, surface characteristics, optical properties, Raman effect, and photoluminescence properties. Cubic shapes Gd2O3:Tb and Y2O3:Tb NPs with an estimated crystalline size of 17 and 11 nm were recorded from the X‐ray diffraction pattern, respectively. Comparative absorption spectra of both oxides NPs were presented to examine the dispersibility, colloidal stability, and optical behavior of the NPs. Energy bandgap values were estimated to monitor the optical characteristics of the metal oxides in the UV/Vis region. Fourier transform infrared was recorded to confirm the surface‐attached water and organic moieties. The Raman spectra of metal oxides were recorded to examine the symmetrical dis‐order and polarizability of the vibrational bands. The ionic radius of the atoms distorts the bond structure resulting in it greatly influenced the vibrational bands of the materials. The emission spectra certified the effective doping of the luminescent Tb3+‐ion in the metal oxide host lattices. Raman spectra and emission spectra validated the crystal symmetry imperfections; subsequently, the efficiency of the Raman active modes and emission transitions was greatly influenced. In a comparative analysis, Y2O3:Tb NPs exhibited higher luminescence intensity in comparison with the Gd2O3:Tb NPs. [ABSTRACT FROM AUTHOR]

The demand for gas-sensing operations with lower electrical power and guaranteed sensitivity has increased over the decades due to worsening indoor air pollution. In this report, we develop room-temperature operational NH3 gas-sensing materials, which are activated through electron doping and crystal structure distortion effect in Fe0.2Ni0.8WO4. The base material, synthesized through solid-state synthesis, involves Fe cations substitutionally located at the Ni sites of the NiWO4 crystal structure and shows no gas-sensing response at room temperature. However, doping Na into the interstitial sites of Fe0.2Ni0.8WO4 activates gas adsorption on the surface via electron donation to the cations. Additionally, the hydrothermal method used to achieve a more than 70-fold increase in the surface area of structure-distorted Na-doped Fe0.2Ni0.8WO4 powder significantly enhances gas sensitivity, resulting in a 4-times increase in NH3 gas response (Rg/Ra). Photoluminescence and XPS results indicate negligible oxygen vacancies, demonstrating that cation contributions are crucial for gas-sensing activities in Na-doped Fe0.2Ni0.8WO4. This suggests the potential for modulating gas sensitivity through carrier concentration and crystal structure distortion. These findings can be applied to the development of room-temperature operational gas-sensing materials based on the cations. [ABSTRACT FROM AUTHOR]

We are proposing a novel self-assembled monolayer (SAM) functionalized ZnO nanowires (NWs)-based conductometric sensor for the selective detection of hydrogen (H2). The modulation of the surface electron density of ZnO NWs due to the presence of negatively charged terminal amine groups (−NH2) of monolayers leads to an enhanced electron donation from H2 to ZnO NWs. This, in turn, increases the relative change in the conductance (response) of functionalized ZnO NWs as compared to bare ones. In contrast, the sensing mechanism of bare ZnO NWs is determined by the chemisorbed oxygen ions. The functionalized ZnO NWs exhibit an eight times higher response compared to bare ZnO NWs at an optimal working temperature of 200 °C. Finally, in comparison to studies in the literature involving strategies to enhance the sensing performance of metal oxides toward H2, like decoration with metal nanoparticles, heterostructures, and functionalization with a metal–organic framework, etc., SAM functionalization showed superior sensing results. [ABSTRACT FROM AUTHOR]

Utilization of actinides and rare earth elements is only possible by separating these metals with high purity. The materials used in separation must have thermal, chemical, mechanical, and radiation resistance. In the present study, separation experiments of actinides and rare earth elements (REEs) were carried out using purified H2SO4 leach liquor. Polyacrylonitrile (PAN)-supported Ti, Zr, and Si oxide nanocomposites were tested for the selective separation of Th, U, Gd, Eu, Sm, Pr, Nd, La, Ce, and Y. The effects of pH, contact time, adsorbent/solution ratio, and temperature on distribution coefficient (KD) and adsorption capacity (Q) were investigated. The synthesized nanocomposites tend to separate the elements into two main groups: Th, U, Gd, Eu and Sm, Pr, Nd, La, Ce. Notably, it was observed that the separation of Th and U from the remaining elements is promising at 15 °C. Additionally, the separation can be further improved depending on the differences in desorption efficiency. [ABSTRACT FROM AUTHOR]

The in-situ electrochemically reconstructed Cu 2 O/CeO 2 from CuO/CeO 2 has been demonstrated to be effective for electrocatalytic carbon dioxide reduction, delivering a high selectivity, activity, and stability for producing CH 4. [Display omitted] Developing an efficient electrocatalyst that enables the efficient electrochemical conversion from CO 2 to CH 4 across a wide potential range remains a formidable challenge. Herein, we introduce a precatalyst strategy that realizes the in situ electrochemical reconstruction of ultrafine Cu 2 O nanodomains, intricately coupled on the CeO 2 surface (Cu 2 O/CeO 2), originating from the heterointerface comprised of ultrafine CuO nanodomains on the CeO 2 surface (CuO/CeO 2). When served as the electrocatalyst for the electrochemical CO 2 reduction reaction, Cu 2 O/CeO 2 delivers a selectivity higher than 49 % towards CH 4 over a broad potential range from −1.2 V to −1.7 V vs. RHE, maintaining negligible activity decay for 20 h. Notably, the highest selectivity for CH 4 reaches an impressive 70 % at −1.5 V vs. RHE. Through the combination of comprehensive analysis including synchrotron X-ray absorption spectroscopy, spherical aberration-corrected high-angle annular dark field scanning transmission electron microscope as well as the density functional theoretical calculation, the efficient production of CH 4 is attributed to the coherent interface between Cu 2 O and CeO 2 , which could converted from the original CuO and CeO 2 interface, ensuring abundant active sites and enhanced intrinsic activity and selectivity towards CH 4. [ABSTRACT FROM AUTHOR]

ABSTRACT To tackle the challenge of non‐destructively analyzing complex oxide layers formed by atmospheric corrosion on active metals, we investigate the potential of inverse spatially offset Raman spectroscopy (inverse‐SORS) to detect corrosion products and elucidate how the spectroscopic features of SORS vary. This study explores the utilization of inverse‐SORS technology for longitudinal structural analysis of opaque CeO2/La2O3 laminates, which serve as a proxy for corrosion products. Through a combination of experimental measurements and Monte Carlo simulation, it demonstrates the feasibility of inverse‐SORS in non‐destructively elucidating the layered structure of these laminates. With increasing the spatial offset of this technology, the Raman intensity ratio of La2O3‐to‐CeO2 increases from 0.23 to 3.2 and then decreases to 0.27 for the CeO2/La2O3 sample with a 34‐μm‐thick CeO2 layer under 532‐nm excitation, whereas the bottom La2O3 layer is hardly detected when the thickness of the upper La2O3 layer increases to 225 μm. The results reveal that a thinner CeO2 layer facilitates the escape and detection of Raman signals originating from the bottom La2O3 layer, leading to an enhanced La2O3‐to‐CeO2 signal ratio and a reduced offset at the characteristic peak. The research also sheds light on the intricate interplay among multiple variables, such as spatial offset, laser wavelength, the corresponding absorption factor, the thickness of the oxide layer, and the compactness. These insights suggest that SORS is a valuable and non‐destructive approach for dissecting the structures of highly turbid composites of metallic compounds and semi‐quantitatively deducing their thickness. [ABSTRACT FROM AUTHOR]

A layered Na2SnO3 with honeycomb structure was synthesized by solid state route using sodium carbonate and tin oxide. The prepared sample was characterized by different physicochemical characterization techniques like X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X‐ray spectroscopy (EDS), X‐ray photoelectron spectroscopy (XPS), ultraviolet visible spectroscopy (UV–vis), photoluminescence spectra (PL), N2 adsorption technique (Brunauer–Emmett–Teller, electrochemical impedance spectroscopy (EIS). The photodegradation of rose bengal dye under UV light was studied. Due to honeycomb structure and high surface area of Na2SnO3, the complete degradation of rose Bengal was observed in 90 min under UV light irradiation. Results of photocatalytic dye degradation reaction demonstrated that Na2SnO3 can be employed as photocatalyst under UV light irradiation. [ABSTRACT FROM AUTHOR]

A novel mixed metal oxide of CuNiO x has been successfully obtained via electrosynthesis and thermal conversion of a Hofmann-type MOF Cu(pz) 2 [Ni(CN) 4 ] (pz = pyrazine). CuNiO x has demonstrated a significant enhancement in light absorption within a visible light range, leading to an impressive increase in photocurrent density and photocatalytic activity during light irradiation compared to CuO. The exceptional photoelectrochemical properties of the photocathodes of CuNiO x have been studied using multiple photoelectrochemical instrumental techniques, which proved the electrodes were stable over the whole water photolysis. The coupling of two metal centers has explained their outstanding performance. • A novel CuNiO x photocathode derived from Hofmann-type MOF was prepared. • CuNiO x shows significant improvement in photocatalytic activity towards H 2 production. • CuNiO x outperforms CuO in hydrogen evolution due to Cu-Ni synergy. • Spectroscopic studies highlight CuO and NiO roles in charge separation. [ABSTRACT FROM AUTHOR]

To meet today's requirements, new active catalysts with reduced noble metal content are needed for hydrogen sensing. A palladium-functionalized nanostructured Ni0.5Co2.5O4 catalyst with a total Pd content of 4.2 wt% was synthesized by coprecipitation to obtain catalysts with an advantageous sheet-like morphology and surface defects. Due to the synthesis method and the reducible nature of Ni0.5Co2.5O4 enabling strong metal-metal oxide interactions, the palladium was highly distributed over the metal oxide surface, as determined using scanning transmission electron microscopy and energy-dispersive X-ray investigations. The catalyst tested in planar pellistor sensors showed high sensitivity to hydrogen in the concentration range below the lower flammability limit (LFL). At 400 °C and in dry air, a sensor response of 109 mV/10,000 ppm hydrogen (25% of LFL) was achieved. The sensor signal was 4.6-times higher than the signal of pristine Ni0.5Co2.5O4 (24.6 mV/10,000 ppm). Under humid conditions, the sensor responses were reduced by ~10% for Pd-functionalized Ni0.5Co2.5O4 and by ~27% for Ni0.5Co2.5O4. The different cross-sensitivities of both catalysts to water are attributed to different activation mechanisms of hydrogen. The combination of high sensor sensitivity to hydrogen and high signal stability over time, as well as low cross-sensitivity to humidity, make the catalyst promising for further development steps. [ABSTRACT FROM AUTHOR]

Wastewater contaminated with cadmium is a concern because of its toxicity, persistence, and bioaccumulation to the environment, ecosystem, and human health, so it is required to remove cadmium(II) ions before releasing them to receiving water. Banana powder beads (BPB), banana powder doped ZnO beads (BPZB), banana powder doped MgO beads (BPMB), and banana powder doped ZnO + MgO beads (BPZMB) were synthesized as the novel cadmium adsorbents, and their characterizations, cadmium adsorption performances, cadmium adsorption patterns and mechanisms, thermodynamic study, and reusability were investigated. BPMB had the highest specific surface area of 16.60 m2/g and the smallest pore size of 1.69 nm than other materials. BPB was an amorphous structure, whereas BPZB, BPMB, and BPZMB were crystalline structures presenting their specific metal oxide peaks of ZnO or MgO. They were coarse surfaces and had a spherical shape consisting of C, O, Ca, Cl, and Na. Their main functional groups were O–H, C–H, C=O, C–O, and N–H. The points of zero charge of BPB, BPZB, BPMB, and BPZMB were 5.37, 6.75, 9.87, and 9.43. The cadmium removal efficiencies of BPB, BPZB, BPMB, and BPZMB were 89.18%, 96.62%, 99.59%, and 97.85%, and their qm values were 90.09, 232.56, 454.55, and 303.03 mg/g, respectively. Thus, the metal oxide helped to improve material efficiency, especially MgO. The Freundlich and pseudo-second-order kinetic models were good fit models for describing their adsorption patterns and mechanisms. The increasing temperature affected to decrease their cadmium adsorptions. They could be reused in more than 3 cycles of more than 73% of cadmium adsorption. The electrostatic interaction played an important role in describing their cadmium adsorptions. Therefore, BPBM was a good cadmium adsorbent for application in industrial wastewater treatment since it had a higher performance of cadmium adsorption than other materials. [ABSTRACT FROM AUTHOR]

Valorizing biodegradable raw materials derived from agri‐waste is ecologically beneficial. Employing such materials to produce adsorbents is a smart platform for applications in wastewater purification. Lignin is one of the most plentiful natural biopolymers in the world. Its macromolecular structure possesses phenolic and carboxyl groups that can capture heavy metals and dyes. Lignin can be chemically and physically modified to generate adsorbent materials with enhanced capacity to remove pollutants from wastewater. In this work, lignin has been used as a natural resource to synthesize metal oxide‐based nanoadsorbents. The synthesized lignin‐based green nanomaterials effectively removed common pollutants from wastewater including dyes, heavy metals, and bacteria. The lignin‐based water purification technique holds immense potential to effectively remove the most common pollutants from wastewater. [ABSTRACT FROM AUTHOR]

The discovery of single-atom catalysts (SACs) represents a groundbreaking advancement in the field of catalysis over the past decades. With the in-depth exploration of relevant structure-activity relationships, the metal-support interaction (MSI) is widely adopted to elucidate variations in electronic structure and coordination configuration of atomic active sites on various kinds of supports. Herein, we briefly summarize the metal oxide supports for SACs fabrication, including the distinctive characteristics of metal oxide supports, enlightening advancements in metal oxide support-based SACs (MO-SACs), feasible preparation methods for MO-SACs and effective regulation strategies of MSI effect in MO-SACs. In addition, we present our viewpoints and outlook in this field to stimulate rational design and construction of novel MO-SACs applied in diverse renewable energy devices, while some universal suggestions are sincerely given to provoke thoughtful considerations during the research process. [ABSTRACT FROM AUTHOR]

Blister-based laser-induced forward transfer (BB-LIFT) is a promising high precision and resolution printing technique for the fast, solvent- and mask-free transfer of functional layered materials onto micro-devices. It utilizes a protective metal (blister) layer sandwiched between the laser-transparent substrate and the material to be transferred. The metal layer absorbs the incident laser pulse, creating a rapidly expanding blister that propels the overlying material onto a target substrate. We show that BB-LIFT of thin and ultrathin (30 and 3 nm) ZrO2 films is realized only with a "graphene release layer" applied between the Al blister layer and the ZrO2 donor layer. Without such intercalation, ZrO2 is inseparable from the blister layer due to the strong oxide bonding with aluminum oxides formed during the preparation. The ZrO2 transfer was confirmed through high-resolution scanning electron microscopy and energy-dispersive X-ray spectroscopy, affirming the critical role of graphene as a release layer. The promotion of mechanically strong, flexible graphene as a release layer can be generalized in BB-LIFT applications if thin films of fragile, polycrystalline, or amorphous metal oxides must be printed for gas sensors, catalytic, or other applications. [ABSTRACT FROM AUTHOR]

Metal oxide core–shell fibrous nanostructures are promising gas-sensitive materials for the detection of a wide variety of both reducing and oxidizing gases. In these structures, two dissimilar materials with different work functions are brought into contact to form a coaxial heterojunction. The influence of the shell material on the transportation of the electric charge carriers along these structures is still not very well understood. This is due to homo-, hetero- and metal/semiconductor junctions, which make it difficult to investigate the electric charge transfer using direct current methods. However, in order to improve the gas-sensing properties of these complex structures, it is necessary to first establish a good understanding of the electric charge transfer in ambient air. In this article, we present an impedance spectroscopy study of networked SnO2/Ga2O3 core–shell nanobelts in ambient air. Tin dioxide nanobelts were grown directly on interdigitated gold electrodes, using the thermal sublimation method, via the vapor–liquid–solid (VLS) mechanism. Two forms of a gallium oxide shell of varying thickness were prepared via halide vapor-phase epitaxy (HVPE), and the impedance spectra were measured at 189–768 °C. The bulk resistance of the core–shell nanobelts was found to be reduced due to the formation of an electron accumulation layer in the SnO2 core. At temperatures above 530 °C, the thermal reduction of SnO2 and the associated decrease in its work function caused electrons to flow from the accumulation layer into the Ga2O3 shell, which resulted in an increase in bulk resistance. The junction resistance of said core–shell nanostructures was comparable to that of SnO2 nanobelts, as both structures are likely connected through existing SnO2/SnO2 homojunctions comprising thin amorphous layers. [ABSTRACT FROM AUTHOR]

Over the last years, a wide variety of nanomaterials have been utilised for the design of highly efficient sensors to detect ammonia (NH3) accurately. Discovery of graphene has dramatically accelerated studies on fabrication of inexpensive electrode materials due to its unique features such as high specific surface area, high carrier mobility, high electrical conductivity, flexibility and optical transparency. Graphene and its derivatives can be readily combined with a variety of inorganic-based nanoparticles such as noble metals, metal oxides and semiconducting, as well as conducting polymers to develop NH3 sensor with excellent sensitivity and very low detection limit. This paper overviews graphene nanocomposite gas sensors as emerging NH3 sensing platforms for the detection of a wide range of NH3 concentration with improved sensitivity, selectivity and a low response and recovery times. Various sensing mechanisms of functionalised graphene nanocomposite gas sensors are explained and compared. Possible opportunities and perspective applications of the graphene NH3 sensors are also presented. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance has emerged as a major global health threat, necessitating the urgent development of new antimicrobials through innovative methods to combat the rising prevalence of resistant microbes. With this view, we developed three novel nanoconjugates using microbial natural pigment for effective application against certain pathogenic microbes. Results: A natural red pigment (RP) extracted from the endophyte Monascus ruber and gamma rays were applied to synthesize RP-ZnO, RP-CuO, and RP-MgO nanoconjugates. The synthesized nanoconjugates were characterized by different techniques to study their properties. The antimicrobial potential of these nanoconjugates was evaluated. Moreover, the antibiofilm, protein leakage, growth curve, and UV light irradiation effect of the synthesized nanoconjugates were also studied. Our results confirmed the nano-size, shape, and stability of the prepared conjugates. RP-ZnO, RP-CuO, and RP-MgO nanoconjugates showed broad antimicrobial potential against the tested bacterial and fungal pathogens. Furthermore, the RP-ZnO nanoconjugate possessed the highest activity, followed by the RP-CuO against the tested microbes. The highest % inhibition of biofilm formation by the RP-ZnO nanoconjugate. Membrane leakage of E. coli and S. aureus by RP-ZnO nanoconjugate was more effective than RP-MgO and RP-CuO nanoconjugates. Finally, UV light irradiation intensified the antibiotic action of the three nanoconjugates and RP-ZnO potential was greater than that of the RP-MgO, and RP-CuO nanoconjugates. Conclusion: These findings pave the way for exploiting the synthesized nanoconjugates as potential materials in biomedical applications, promoting natural, green, and eco-friendly approaches. [ABSTRACT FROM AUTHOR]

Free of posttransfer, on-surface synthesis (OSS) of single-atomic-layer nanostructures directly on semiconductors holds considerable potential for next-generation devices. However, due to the high diffusion barrier and abundant defects on semiconductor surfaces, extended and well-defined OSS on semiconductors has major difficulty. Furthermore, given semiconductors' limited thermal catalytic activity, initiating high-barrier reactions remains a significant challenge. Herein, using TiO2(011) as a prototype, we present an effective strategy for steering the molecule adsorption and reaction processes on semiconductors, delivering lengthy graphene nanoribbons with extendable widths. By introducing interstitial titanium (Tiint) and oxygen vacancies (Ov), we convert TiO2(011) from a passive supporting template into a metal-like catalytic platform. This regulation shifts electron density and surface dipoles, resulting in tunable catalytic activity together with varied molecule adsorption and diffusion. Cyclodehydrogenation, which is inefficient on pristine TiO2(011), is markedly improved on Tiint/Ov-doped TiO2. Even interribbon cyclodehydrogenation is achieved. The final product's dimensions, quality, and coverage are all controllable. Tiint doping outperforms Ov in producing regular and prolonged products, whereas excessive Tiint compromises molecule landing and coupling. This work demonstrates the crucial role of semiconductor substrates in OSS and advances OSS on semiconductors from an empirical trial-and-error methodology to a systematic and controllable paradigm. [ABSTRACT FROM AUTHOR]

Metal-organic framework (MOF) derived metal oxide nanostructures hold immense promise as electrodes for energy storage/conversion applications, notably in supercapacitors and urea oxidation. This study explores into optimizing such nanostructures, specifically focusing on a Zr/Ni ratio of 1:1, which has exhibited favorable electrochemical and catalytic performance. Employing thorough characterization methods, including PXRD analysis, we verified the successful synthesis of a ZrO 2 /NiO binary phase (i.e. Zr/Ni) nanostructure via the MOF-derived approach, showcasing its versatility as a catalyst across diverse energy conversion domains. The Zr/Ni nanostructure electrode displayed noteworthy characteristics, boasting a capacity of 432 C/g alongside exceptional cycling stability of 99%, reflecting battery-like electrochemical behavior. Furthermore, in an asymmetric device setup (Zr/Ni//AC), it achieved a notable potential of up to 1.4 V with an impressive power density of 1044.56 W/kg. Additionally, the Zr/Ni nanostructure demonstrated efficient electrocatalytic activity in urea oxidation, evidenced by a maximum current density of 60 mA/cm2. This underscores its viability as a preferred catalyst in energy conversion applications, signaling opportunities for further exploration and advancement in this dynamic field. [Display omitted] • Successful formation of a binary phase of Zr/Ni nanostructure achieved by single step route. • Zr/Ni nanostructure demonstrated a specific capacity of 432C/g. • Zr/Ni//AC device showed ED of 4.08 Wk/g@ 420 W/kg. • Zr/Ni nanostructure exhibits a low onset voltage (1.34 V) in urea oxidation. • Zr/Ni nanostructure shows the highest current density of 60 mA/cm2. [ABSTRACT FROM AUTHOR]

This comprehensive review delves into the burgeoning field of nanotechnology, where the synthesis of nanoparticles (NPs) is strategically tailored to specific applications. Embracing the principles of green chemistry, nanotechnology increasingly utilizes environmentally friendly materials, such as plant extracts or microorganisms, as capping or reducing agents and solvents in the synthesis process. Notably, plant-based synthesis demonstrates enhanced stability and faster rates compared to microorganisms. The synthesized materials exhibit unique properties ranging from antimicrobial and catalytic effects to antioxidant activities and they are finding applications across diverse fields. Green synthesis processes, characterized by mild conditions in terms of temperature and reagents, stand in stark contrast to traditional chemical synthesis methods. This review focuses on the synthesis of various metal and metal oxide NPs, including Ag, Au, Zn, Fe, Mg, Ti, Sn, Cu, Cd, Ni, Co, and Ag NPs and their oxides, using plant extracts and microorganisms. We provide a comprehensive analysis of the advantages, disadvantages, and applications associated with each synthesis method. Additionally, we explore the future prospects of green synthesis and its limitations and challenges, offering insights into its evolving role in nanotechnology. [ABSTRACT FROM AUTHOR]

Polymeric sheets of poly(methyl methacrylate) loaded with organic dye with various amounts of metal oxide nanopowder are promising alternatives to traditional inorganic materials, as they have similar mechanical properties to flexible substrates with relatively high refractive index that can be used in flexible optical/optoelectronic devices. Polymeric sheets of poly(methyl methacrylate) loaded with boron subphthalocyanine chloride with various amounts of cerium(IV)-zirconium(IV) oxide nanopowder were fabricated. Fourier transform infrared spectroscopy and X-ray diffraction techniques were used to examine and analyse the structure of the fabricated polymer sheets. Introducing organic dye and nanofiller in the polymer molecular chains matrix does not change the infrared characteristic transmission peaks. The X-ray diffraction spectra of the polymeric sheets have an amorphous nature. Characterized by spectroscopic measurements (fluorescence, transmittance, and reflectance), the optical properties such as the optical energy gap, emission bands, and refractive index of the fabricated polymer sheets were explored. By controlling the concentration of boron subphthalocyanine chloride and cerium(IV)-zirconium(IV) oxide nanopowder, energy gaps and the refractive indexes of the fabricated polymer sheets can be controlled. The poly(methyl methacrylate) loaded with boron subphthalocyanine chloride with 20 mg cerium(IV)-zirconium(IV) oxide nanopowder showed optical energy gap transitions at 4.79, 2.66 eV, and 2.08 eV, it has the highest PL intensity with a strong emission band at 413 nm, and also it has the highest refractive index. Finally, the obtained experimental results showed that the prepared polymer systems can be considered promising flexible polymer sheets for optics, and photonics devices. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of a multicomponent metal oxide electrocatalyst that increases the activity of the oxygen evolution reaction (OER). We synthesized transition metal oxides (MnOx, FeOx, CoOx, and NiOx) with MoO3 heterostructures through a solid-state reaction approach at low cost. In comparison to the other compositions, CoOx garnered higher attention and demonstrated superior performance on account of its large surface area and varied crystal facets. The MnOx-MoO3, FeOx-MoO3, CoOx-MoO3, and NiOx-MoO3 compositions attained an overpotential of 390 mV, 350 mV, 310 mV, and 340 mV, respectively, at a current density of 10 mA cm−2 in alkaline solution. The performance of OER was enhanced in CoOx-MoO3 at 10 mA cm−2, while FeOx-MoO3 exhibited a lower current density at 100 mA cm−2 than other metal oxides. The CoOx-MoO3 material exhibited a favorable crystal interface transition due to the presence of MoO3 oxide. For the first time, we report on the MoO3-to-(MnOx, FeOx, CoOx, and NiOx) interface crystal transition and the active surface area for OER catalytic activity in water-splitting processes. This investigation intends to develop an electrocatalyst that is capable of producing hydrogen with the use of heterostructure metal oxides. [ABSTRACT FROM AUTHOR]

Biopolymer blend based nanocomposites have been interestingly investigated by researchers to achieve advanced composite functional materials that are environmentally amicable. Among the varieties of biopolymers, widespread attention has been given to polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) owing to their interesting properties like water solubility, biodegradability, biocompatibility and non-toxicity. PVA and PVP form a completely miscible blend at all compositions as both the polymers are rich in a variety of functional groups that permit effective intermolecular interactions between the polymers as well as with filler. PVA/PVP blend exhibits excellent dopant sensitive properties also. Metal oxide nanoparticles (MONPs) have made a prominent place in the area of scientific and technological research due to their unique chemical and physical properties. Doping with MONPs enhances the properties of the PVA/PVP blend matrix and the resulting PVA/PVP/MONP polymer nanocomposites are suitable for multifunctional purposes. This review mainly focused on the influence of various MONPs such as ZnO, CuO, Al2O3, ZrO2, MnO, SnO, MgO, TiO2, etc. in the structural, morphological, thermal, optical and electrical properties of PVA/PVP blend as well as its applications in various fields. [ABSTRACT FROM AUTHOR]

Buildings worldwide are becoming more thermally insulated, and air circulation is being reduced to a minimum. As a result, measuring indoor air quality is important to prevent harmful concentrations of various gases that can lead to safety risks and health problems. To measure such gases, it is necessary to produce low-cost and low-power-consuming sensors. Researchers have been focusing on semiconducting metal oxide (SMOx) gas sensors that can be combined with intelligent technologies such as smart homes, smart phones or smart watches to enable gas sensing anywhere and at any time. As a type of SMOx, p-type gas sensors are promising candidates and have attracted more interest in recent years due to their excellent electrical properties and stability. This review paper gives a short overview of the main development of sensors based on copper oxides and their composites, highlighting their potential for detecting CO2 and the factors influencing their performance. [ABSTRACT FROM AUTHOR]

• Wider variety of artefacts needs to be conserved. • NPs based coating have the potency to replace the traditional coating materials. • The NPs improved the photo-catalysis, hydrophobicity and antibacterial properties. The progression in the use of nanostructured metal oxide or metal oxide based polymeric nanocomposite for the conservation and refurbishment of cultural heritage are presented in this review. Starting from the definition of nanoparticles, their major synthesis techniques, the paper briefly describes the utilization of various metal oxide nanoparticles and metal oxide based polymeric nanocomposite coatings and their surface protection functions including self-cleaning, increased photocatalytic activity, biocidal effects, UV blocking properties and compatibility with the different types of substrates including wood, stones, bricks and paper focussing on their potential usage and their application in the arena of remediation of cultural heritage. [Display omitted] [ABSTRACT FROM AUTHOR]

The generation of oxygen vacancies and Bi-metal on BiVO 4 enhances conductivity, extending both catalytic activity and cyclability in Li–O 2 batteries. [Display omitted] Bismuth Vanadate (BiVO 4) is a promising oxide-based photoanode for electrochemical applications, yet its practical use is constrained by poor charge transport properties, particularly under dark conditions. This study introduces a novel BiVO 4 variant (Bi-BiVO 4 -10) that incorporates abundant oxygen vacancies and in-situ formed Bi metal, significantly enhancing its electrical conductivity and catalytic performance. Bi-BiVO 4 -10 demonstrates superior electrochemical performances compared to conventional BiVO 4 (C-BiVO 4), demonstrated by its most positive half-wave potential with the highest diffusion-limiting current in the oxygen reduction reaction (ORR) and earliest onset potential in the oxygen evolution reaction (OER). Notably, Bi-BiVO 4 -10 is explored for the first time as an electrocatalyst for lithium-oxygen (Li–O 2) cells, showing reduced overcharge (610 mV) in the first cycle and extended cycle life (1050 h), outperforming carbon (320 h) and C-BiVO 4 (450 h) references. The enhancement is attributed to the synergy of oxygen vacancies, Bi metal formation, increased surface area, and improved electrical conductivity, which collectively facilitate Li 2 O 2 growth, enhance charge transport kinetics, and ensure stable cycling. Theoretical calculations reveal enhanced chemical interactions between intermediate molecules and the defect-rich surfaces of Bi-BiVO 4 -10, promoting efficient discharge and charge processes in Li–O 2 batteries. This research highlights the potential of unconventional BiVO 4 -based materials as durable electrocatalysts and for broader electrochemical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Water splitting is a promising technique for clean hydrogen production. To improve the sluggish hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), the development of efficient bifunctional electrocatalysts for both HER and OER is urgent to approach the scale-up applications of water splitting. Nowadays transition metal oxides (TMOs) are considered as the promising electrocatalysts due to their low cost, structural flexibility and stability, however, their electrocatalytic activities are eager to be improved. Here, we synthesized waxberry-like hydrophilic Co-doped ZnFe 2 O 4 electrocatalysts as bifunctional electrocatalysts for water splitting. Due to the enhanced active sites by electronic structure tuning and modified super-hydrophilic characteristics, the spinel ZFO-Co 0.5 electrocatalyst exhibits excellent catalytic activities for both OER and HER. It exhibits a remarkable low OER overpotential of 220 mV at a current density of 10 mA cm−2 and a Tafel slope of 28.2 mV dec-1. Meanwhile, it achieves a low overpotential of 73 mV at a current density of 10 mA cm−2 with the Tafel slope of 87 mV dec-1 for HER. In addition, for water electrolysis device, the electrocatalytic performance of ZFO-Co 0.5 ||ZFO-Co 0.5 surpasses that of commercial IrO 2 ||Pt/C. Our work reveals that the hydrophilic morphology regulation combined with metallic doping strategy is a facile and effective approach to synthesize spinel TMOs as excellent bifunctional electrocatalyst for water splitting. [ABSTRACT FROM AUTHOR]

Tuning the interfacial structure of metal oxide substrates is an essential strategy to induce electronic structure reconstruction of supported catalysts, which is of great importance in optimizing their catalytic activities. Herein, vanadium oxides‐supported Ir catalysts (Ir‐V2O3, Ir‐VO2, and Ir‐V2O5) with different interfacial bonding environments (Ir‐V, Ir‐Obri, and Ir‐O, respectively) were investigated for hydrogen evolution reaction (HER). The regulating mechanism of the influence of different interfacial bonding environments on HER activity was investigated by both experimental results and computational evidence. Benefiting from the unique advantages of interfacial Ir‐V direct metal bonds in Ir‐V2O3, including enhanced electron transfer and electron donation ability, an optimized HER performance can be obtained with lowest overpotentials of 16 and 26 mV at 10 mA cm−2, high mass activities of 11.24 and 6.66 A mg−1, and turnover frequency values of 11.20 and 6.63 s−1, in acidic and alkaline conditions respectively. Furthermore, the assembled Ir‐V2O3||RuO2 anion exchange membrane (AEM) electrolyzer requires only 1.92 V to achieve a high current density of 500 mA cm−2 and realizes long‐term stability. This study provides essential insights into the regulating mechanism of interfacial chemical bonding in electrocatalysts and offers a new pathway to design noble metal catalysts for different applications. [ABSTRACT FROM AUTHOR]

Tuning the interfacial structure of metal oxide substrates is an essential strategy to induce electronic structure reconstruction of supported catalysts, which is of great importance in optimizing their catalytic activities. Herein, vanadium oxides‐supported Ir catalysts (Ir‐V2O3, Ir‐VO2, and Ir‐V2O5) with different interfacial bonding environments (Ir‐V, Ir‐Obri, and Ir‐O, respectively) were investigated for hydrogen evolution reaction (HER). The regulating mechanism of the influence of different interfacial bonding environments on HER activity was investigated by both experimental results and computational evidence. Benefiting from the unique advantages of interfacial Ir‐V direct metal bonds in Ir‐V2O3, including enhanced electron transfer and electron donation ability, an optimized HER performance can be obtained with lowest overpotentials of 16 and 26 mV at 10 mA cm−2, high mass activities of 11.24 and 6.66 A mg−1, and turnover frequency values of 11.20 and 6.63 s−1, in acidic and alkaline conditions respectively. Furthermore, the assembled Ir‐V2O3||RuO2 anion exchange membrane (AEM) electrolyzer requires only 1.92 V to achieve a high current density of 500 mA cm−2 and realizes long‐term stability. This study provides essential insights into the regulating mechanism of interfacial chemical bonding in electrocatalysts and offers a new pathway to design noble metal catalysts for different applications. [ABSTRACT FROM AUTHOR]

Triethylamine is a common volatile organic compound (VOC) that plays an important role in areas such as organic solvents, chemical industries, dyestuffs, and leather treatments. However, exposure to triethylamine atmosphere can pose a serious threat to human health. In this study, gas-sensing semiconductor materials of LaFeO3 nano materials with different Mo-doping ratios were synthesized by the sol–gel method. The crystal structures, micro morphologies, and surface states of the prepared samples were characterized by XRD, SEM, and XPS, respectively. The gas-sensing tests showed that the Mo doping enhanced the gas-sensing performance of LaFeO3. Especially, the 4% Mo-doped LaFeO3 exhibited the highest response towards triethylamine (TEA) gas, a value approximately 11 times greater than that of pure LaFeO3. Meantime, the 4% Mo-doped LaFeO3 sensor showed a remarkably robust linear correlation between the response and the concentration (R2 = 0.99736). In addition, the selectivity, stability, response/recovery time, and moisture-proof properties were evaluated. Finally, the gas-sensing mechanism is discussed. This study provides an idea for exploring a new type of efficient and low-cost metal-doped LaFeO3 sensor to monitor the concentration of triethylamine gas for the purpose of safeguarding human health and safety. [ABSTRACT FROM AUTHOR]

The demand for gas sensing systems that enable fast and precise gas recognition is growing rapidly. However, substantial challenges arise from the complex fabrication process of sensor arrays, time‐consuming data transmission to an external processor, and high energy consumption in multi‐stage data processing. In this study, a gas sensing system using on‐chip annealing for fast and power‐efficient gas detection is proposed. By utilizing a micro‐heater embedded in the gas sensor, the sensing material of adjacent sensors in the same substrate can be easily varied without further fabrication steps. The response to oxidizing gas is constrained in metal oxide (MOX) sensing material with small grain sizes, as the depletion width of grain cannot extend beyond the grain size during the gas reaction. On the other hand, the response to reducing gases and humidity, which decrease the depletion width, is less affected by grain sizes. A readout circuit integrating a differential amplifier and dual FET‐type gas sensors effectively emphasizes the response to oxidizing gases by canceling the response to reducing gases and humidity. The selective on‐chip annealing method is applicable to various MOX sensing materials, demonstrating its potential for application in commercial fields due to its simplicity and expandability. [ABSTRACT FROM AUTHOR]

The use of structured metal oxide-based nanoparticles for environmental proposals arises from the adverse impact of human industrial activities that threaten the fragile balance of the environment. These nanomaterials characterized by their chemical and mechanical stability, modifiable bandgap, remarkable textural features, and notable optoelectronic properties have an important role in removing pollutants from the environment. Metal oxide-based nanoparticles have demonstrated remarkable capabilities by removing pollutants such as herbicides, microplastics, dyes, pesticides, antibiotics, microbial organisms, and heavy metals. Additionally, these materials can be incorporated into sensing devices for real-time monitoring and identification of pollutants in air, water, and soil, facilitating environmental risk assessment and pollution control. Nevertheless, the successful implementation of semiconductor nanoparticles faces drawbacks and challenges, including scalability, cost-effectiveness, and potential environmental impacts, necessitating thorough consideration. Ongoing research and development efforts are crucial to further explore the potential of semiconductor nanoparticles for practical solutions. The anticipated growth in the use of these nanomaterials in various commercial applications foresees a more sustainable and environmentally friendly future. Thus, this document aims to present how nanoparticles with diverse forms and adjustable physicochemical properties are a tool to conserve the ecological balance. [ABSTRACT FROM AUTHOR]

The textile industry is consistently integrating cutting-edge technologies, introducing materials with multifaceted features, such as odour resistance, hydrophobicity, durability, and self-cleaning capabilities. This transformation is facilitated by the application of nanotechnology. The focal point of this experimental endeavour lies in closing the gap in employing ZnO nanoparticles on high GSM denim fabric, enhancing self-cleaning, UV protection, and antimicrobial capabilities. Initially, a solution containing nanoparticles, binder, softener, ethanol, and their auxiliaries was formulated. Zinc oxide nanoparticles, along with their auxiliaries, were applied to the denim using the pad-dry-cure and pad-dry-steam methods. Various trials were conducted to optimize the concentration of ZnO NPs, with the formulation containing 5% ZnO NPs, 5% binder, and 25% ethanol. Experimentation ensued to establish optimal time-temperature profiles for drying, curing, and steaming. Comprehensive evaluations, including drop tests, stain tests, colour strength assessments, crocking tests, SEM analysis, antimicrobial testing and UV protection factor determination were conducted on the samples. The study revealed that fixation of the self-cleaning finish by curing gives better results than by steaming. SEM examination highlighted the distribution of ZnO nanoparticles on the denim fabric. Lastly, antimicrobial properties were assessed, concluding that treated fabrics exhibited antibacterial activity compared to untreated fabrics. [ABSTRACT FROM AUTHOR]

In this study, the results of the investigation of the influence of Al atoms on the structural characteristics of ZnO films obtained by the sol- gel method are presented. It has been determined that the glass substrates consist of subcrystallites with dimensions of 28.6 nm, having cubic unit cells with lattice parameters a = 0.3336 nm, and their surfaces belong to the crystallographic orientation (111). It has been identified that the grown thin ZnO films consist of subcrystallites with dimensions of 39.5 nm, having a wurtzite structure with lattice parameters a = b = 0.3265 nm and c = 0.5212 nm, respectively. It has been determined that at the boundaries of the division of these subcrystallites, polycrystalline regions with sizes of 12.6 nm, 28.3 nm, 30 nm, and 33 nm are formed. Additionally, nanocrystallites with sizes of 56.8 nm self-assemble on the surface areas of the deposited films. The increase in the values of the "c"axis of the hexagonal crystal lattice of ZnO films by 0.0009 nm when doping Al atoms from 1% to 5% is explained by the shift of the main structural line (002) at small angles (40-0.12°). It has been established that nanocrystallites with lattice parameters an = 0.5791 nm, belonging to the spatial group Fd3m, self-assemble on the surface areas of ZnO:Al films. the curve due to the presence of a monoenergetic level of fast surface states at the heterojunction. [ABSTRACT FROM AUTHOR]

Resistive Random Access Memory (RRAM) is a prominent contender in the realm of emerging non-volatile memory technologies owing to its numerous advantages like simple structure, low power usage, high speed, and exceptional scalability. In the current study, RRAM device was fabricated using tantalum oxide (TaOx) as a resistive switching insulating oxide layer, which was sandwiched between two conducting electrodes, namely Ag and ITO. RF magnetron sputtering was used to deposit the insulating layer of TaOx at room temperature on the ITO substrate. Further, X-ray reflectivity and hard X-ray photoelectron spectroscopy analyses were conducted to find the thickness, roughness, and elemental composition of the deposited TaOx films. Using a semiconductor analyzer, the RRAM cell's first DC switching characteristics were determined. The data acquired exhibited a resistance ratio (RHRS/RLRS) of 120 showing a good distinction between the two-resistance states. Additionally, a thorough investigation was conducted to examine the electrical conduction mechanism occurring inside the fabricated RRAM device. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WO3) is a well-known transition metal oxide that demonstrates stability and non-toxicity in its nanoparticle form. Because of its facile and cost-effective synthesis method, it is a promising candidate for several applications like electrochromic devices, photo catalysts and gas sensors. In the present work, WO3 nanoparticles were synthesized through a one-step hydrothermal process. Subsequently, the pure WO3 sample underwent doping with different materials, including Cr+ 3, Co+ 2, Ag+ 1, Hg+ 1 and Pb+ 4. The crystallographic properties and phase transitions of the crystalline substances were demonstrated by the structural characterisation of all the as-synthesised materials using the X-ray diffraction technique. The optical properties were explored by UV-visible spectroscopy, revealing the energy band gap from 2.53 eV to 3.75 eV. Field Emission Scanning electron microscopy (FESEM) images depicted the morphological features of the material. The pure WO3 exhibited a 2D nanosheet structure, while the doped materials displayed morphologies ranging from nanosheets or nanorods to polyhedral sheets. Microstructural analysis by TEM revealed particle size for all samples along with fringes and SAED pattern confirming the presence of respective planes. The electrochemical properties of the synthesized samples were investigated using Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV) techniques. This research delves into exploring the electrochemical sensing potential of tungsten oxide doped with chromium, cobalt, silver, mercury, and lead as thin layer working electrodes, driven by the pressing need for advancements in sensing technologies. Through a comprehensive investigation of their electrochemical and optical characteristics, this study aims to discern their suitability for sensing applications, providing insights crucial for future sensor design and synthesis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Desulfurization in waste tire pyrolysis oil and gas was achieved by metal oxides. • Fe 2 O 3 shows the best removal efficiency of 87.7% for sulfur-containing gas. • The desulfurization mechanism was revealed by ReaxFF-MD and experiments analysis. • The removal of S involved Fe-S bonding, C-S breakage, dehydrogenation, O migration. • Fe 2 O 3 promotes cyclization and dehydrogenation to produce monoaromatics (57.4%). Pyrolysis can effectively convert waste tires into high-value products. However, the sulfur-containing compounds in pyrolysis oil and gas would significantly reduce the environmental and economic feasibility of this technology. Here, the desulfurization and upgrade of waste tire pyrolysis oil and gas were performed by adding different metal oxides (Fe 2 O 3 , CuO, and CaO). Results showed that Fe 2 O 3 exhibited the highest removal efficiency of 87.7 % for the sulfur-containing gas at 600 °C with an outstanding removal efficiency of 99.5 % for H 2 S. CuO and CaO were slightly inferior to Fe 2 O 3 , with desulfurization efficiencies of 75.9 % and 45.2 % in the gas when added at 5 %. Fe 2 O 3 also demonstrated a notable efficacy in eliminating benzothiophene, the most abundant sulfur compound in pyrolysis oil, with a removal efficiency of 78.1 %. Molecular dynamics simulations and experiments showed that the desulfurization mechanism of Fe 2 O 3 involved the bonding of Fe-S, the breakage of C-S, dehydrogenation and oxygen migration process, which promoted the conversion of Fe 2 O 3 to FeO, FeS and Fe 2 (SO 4) 3. Meanwhile, Fe 2 O 3 enhanced the cyclization and dehydrogenation reaction, facilitating the upgrade of oil and gas (monocyclic aromatics to 57.4 % and H 2 to 22.3 %). This study may be helpful for the clean and high-value conversion of waste tires. [ABSTRACT FROM AUTHOR]

The chief source of water pollution is industrial wastewater containing dyes. In current study, the optimum conditions for removal of Red-XGRL dye by green metal oxide polymeric nanocomposites were determined via batch and column study. The synthesized materials were characterized via SEM, FTIR and thermal analysis. The optimum pH for attaining maximum adsorption capacity of WD, WD-ZnO-PTh, WD-ZnO-PAN and WD-ZnO-PPY was found to be 8 (12.9 mg/g), 10 (30.2 mg/g), 11 (35.8 mg/g) and 11 (40 mg/g), respectively, and optimum dose was found to be 0.05 g/50 mL. The highest adsorption potential for all composite materials was attained within 90 min and maximum adsorption potential for WD (40.8 mg/g), WD-ZnO-PTh (60.7 mg/g), WD-ZnO-PAN (70.4 mg/g) and WD-ZnO-PPY (86.3 mg/g) was obtained using 200 mg/L dye concentration at 30 °C. The adsorption data showed better fitness to pseudo-second-order kinetics and Langmuir sorption isotherm giving significant R2 values of 0.95–0.99 and 0.97–0.99, respectively. Thermodynamic study showed exothermic nature of sorption. During column study, optimum adsorbent bed height, dye flow rate and inlet initial dye concentration to attain highest adsorption (35 mgg−1) were determined to be 3 cm, 1.8 mL min−1 and 70 mg/L, respectively. Hence, the present study aimed to remove Red-XGRL dye proved that these green metal oxide polymeric nanocomposites could efficiently be synthesized and utilized for efficient removal of Red-XGRL dye from aqueous solution both in batch and in column mode. [ABSTRACT FROM AUTHOR]

To address the problem that vitamin C wastewater is difficult to meet the discharge standard after secondary biochemical treatment. The mixed metal oxide (MMO) ozone catalysts were prepared for the degradation of vitamin C biochemical wastewater by using mixed iron and aluminum powders as the carriers (Fe2O3/Al2O3FA) doped and mixed with other metal oxide powders by the rolling granulation method. The results showed that the MMO ozone catalyst Cu-Ni/FA prepared by the synergistic catalysis of CuO and Ni2O3 had better catalytic and mechanical properties. The physicochemical properties of the samples were characterized by SEM, TEM, BET, XRD, and XPS, and 让 was found that NiFe2O3 and Cu4O3 played an important role in the catalytic system. Under the conditions of wastewater COD eoncentration of 248. 31 mg/L, pH 7, catalyst add让ion of 35 g/L, and ozone dosage of 10 mg/L, the COD removal efficiency reached 70% at 60 min. The catalyst shedding rate was 2. 724% after 120 min of ultrasonication, and the catalytic ozone oxidation experiments were carried out on the catalyst after each ultrasonication. The COD removal rate was 65% ~69%, which indicated that the catalyst had good anti-shedding properties and stability. [ABSTRACT FROM AUTHOR]

AbstractMetal oxide nanoparticles (MONs) are attractive new technology for numerous applications in optic, magnetic, and electronic devices, UV absorbents, food processing, paints, adhesives, bio-imaging, catalytic sensing, coatings, membranes, insulation, flame retardants, pharmaceutical, and other biomedical applications which have triggered the essential for their easily obtained and reproducible preparation with a better control over their size, shape, crystal structure, and surface chemistry. This review covers the fundamental science, chemical synthesis, and properties of various metal oxide nanostructures. An overview of the recent developments and applications of MONs have been presented. The review summarizes the most recent considerable advances and discusses them critically, providing selected examples, clarifying, and illustrating the important principles, and bringing together many important references of primary literature. The major challenges faced and future trends on the usage of such MONs have also been discussed. [ABSTRACT FROM AUTHOR]

For enhanced security in hardware‐based security devices, it is essential to extract various independent characteristics from a single device to generate multiple keys based on specific values. Additionally, the secure destruction of authentication information is crucial for the integrity of the data. Doped amorphous indium gallium zinc oxide (a‐IGZO) thin‐film transistors (TFTs) using poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) induce a dipole doping effect through a phase‐transition process, creating physically unclonable function (PUF) devices for secure user information protection. The PUF security key, generated at VGS = 20 V in a 20 × 10 grid, demonstrates uniformity of 42% and inter‐Hamming distance (inter‐HD) of 49.79% in the β‐phase of PVDF‐HFP. However, in the γ‐phase, the uniformity drops to 22.5%, and inter‐HD decreases to 35.74%, indicating potential security key destruction during the phase transition. To enhance security, a multi‐factor authentication (MFA) system is integrated, utilizing five security keys extracted from various TFT parameters. The security keys from turn‐on voltage (VON), VGS = 20 V, VGS = 30 V, mobility, and threshold voltage (Vth) exhibit near‐ideal uniformities and inter‐HDs, with the highest values of 58% and 51.68%, respectively. The dual security system, combining phase transition and MFA, establishes a robust protection mechanism for privacy‐sensitive user information. [ABSTRACT FROM AUTHOR]

This study proposes a new modification of lignocellulosic biomass based on apricot kernel shells with composite activation KI/KOH and functionalized with a tolerant material (MgO) powder. Apricot kernel shells (NAK), modified apricot kernel shells (MAK) and doped apricot kernel shells (DAK) obtained were characterized using various methods, such as infrared spectroscopy (FTIR), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and point of zero charge (pHpzc). The adsorbents were also evaluated in batch adsorption, using basic fuchsine dye (BF) to determine the performance and specific capacity of the adsorption process. The results showed that only 90 min and 0.1 g of DAK or MAK are sufficient to remove 93% and 91%, respectively, of basic fuchsine from aqueous solutions with a concentration of 20 mg/L in a volume of 100 mL. The MAK and DAK adsorbents can be reused for 5 cycles before their yield decreases below 50%, without requiring complex regeneration procedures, only drying for 4 h at 105°C. The evolution of adsorption was analyzed under different parameters, such as contact time, initial dose of adsorbent, initial dye concentration, initial pH, and temperature. The kinetic adsorption models indicate that the pseudo-second-order model was more suitable than the pseudo-first-order and intraparticle diffusion models for describing the adsorption process. The equilibrium adsorption data of BF were better fitted by the Langmuir isotherm, compared to the Freundlich and Temkin isotherms. [ABSTRACT FROM AUTHOR]

In this work, copper oxide (CuO) thin films were prepared using the pulsed laser deposition (PLD) technique. The effect of laser beam energy and pulse number on the structural, morphological, and topographical characteristics was investigated. X-ray diffraction (XRD) results indicate the presence of characteristic peaks for CuO with a crystalline growth orientation at the (111) plane and an increase in crystallite size (D) when the laser power and number of pulses increase. EDX results indicate the presence of distinct energy peaks for the copper and oxygen elements that form CuO, and the weight percentage (wt.%) of Cu increases with increasing laser energy. The atomic force microscope (AFM) results showed the dependence of the roughness on the laser energy used, as the roughness decreased from 31.18 to 20.89 nm when the energy increased from 700 to 820 mJ. It increases with the increase in the number of laser pulses at the same energy (700 mJ). Field emission scanning electron microscopy (FESEM) confirms the presence of sub-spherical nanoparticles, and increasing laser energy and pulses increases nanoparticle size. [ABSTRACT FROM AUTHOR]

A series of metal- and silica-containing carbon-based nanocomposites were synthesized by pyrolysis of a resorcinol–formaldehyde polymer modified with metal oxide/silica nanocomposites (MxOy/SiO2, where M = Mg, Mn, Ni, Cu and Zn) via the thermal oxidative destruction of metal acetates adsorbed on highly dispersed silica (A380). The concentration of metals was 3.0 mmol/g SiO2. The phase composition and morphological, structural and textural properties of the carbon materials were analyzed by X-ray diffraction, SEM, Raman spectroscopy and low-temperature N2 adsorption. Thermal decomposition under a nitrogen atmosphere and in air was analyzed using TG–FTIR and TG–DTG–DSC techniques to determine the influence of the filler on the decomposition process. The synthesized composites show mesoporous structures with high porosity and narrow pore size distributions. It could be shown that the textural properties and the final composition of the nanocomposites depend on the metal oxide fillers of the precursors. The data obtained show that nickel and copper promote the degree of graphitization and a structural order with the highest porosity and largest specific surface area of the hybrid composites. The good adsorption properties of the obtained materials were shown for the recovery of p-chlorophenol and p-nitrophenol from aqueous solutions. [ABSTRACT FROM AUTHOR]

As a stable, low-cost, environment-friendly, and gas-sensitive material, semiconductor metal oxides have been widely used for gas sensing. In the past few years, single-atom catalysts (SACs) have gained increasing attention in the field of gas sensing with the advantages of maximized atomic utilization and unique electronic and chemical properties and have successfully been applied to enhance the detection sensitivity and selectivity of metal oxide gas sensors. However, the application of SACs in gas sensors is still in its infancy. Herein, we critically review the recent advances and current status of single-atom catalysts in metal oxide gas sensors, providing some suggestions for the development of this field. The synthesis methods and characterization techniques of SAC-modified metal oxides are summarized. The interactions between SACs and metal oxides are crucial for the stable loading of single-atom catalysts and for improving gas-sensitive performance. Then, the current application progress of various SACs (Au, Pt, Cu, Ni, etc.) in metal oxide gas sensors is introduced. Finally, the challenges and perspectives of SACs in metal oxide gas sensors are presented. [ABSTRACT FROM AUTHOR]

Highlights: Surface energy and surface Pourbaix diagram reveal that ZrO2 ( 1 ¯ 11 ) is the most thermodynamically stable facet and is preferentially occupied by HO* at the equilibrium potential of oxygen evolution reaction (OER). Microkinetic modeling analyzed the OER activity of 40 single-metal doped ZrO2 and identified 16 metals exhibit improved catalytic activity, with Rh and Fe dopants showing the remarkable improvement. Thermodynamic free energy diagrams, density of states analysis, and ab initio molecular dynamics simulations further confirm that Fe–ZrO2 and Rh–ZrO2 are highly promising catalysts for OER, showcasing low ΔG for the rate-determining step, high conductivity, and exceptional stability. The design of cost-effective electrocatalysts is an open challenging for oxygen evolution reaction (OER) due to the "stable-or-active" dilemma. Zirconium dioxide (ZrO2), a versatile and low-cost material that can be stable under OER operating conditions, exhibits inherently poor OER activity from experimental observations. Herein, we doped a series of metal elements to regulate the ZrO2 catalytic activity in OER via spin-polarized density functional theory calculations with van der Waals interactions. Microkinetic modeling as a function of the OER activity descriptor (GO*-GHO*) displays that 16 metal dopants enable to enhance OER activities over a thermodynamically stable ZrO2 surface, among which Fe and Rh (in the form of single-atom dopant) reach the volcano peak (i.e. the optimal activity of OER under the potential of interest), indicating excellent OER performance. Free energy diagram calculations, density of states, and ab initio molecular dynamics simulations further showed that Fe and Rh are the effective dopants for ZrO2, leading to low OER overpotential, high conductivity, and good stability. Considering cost-effectiveness, single-atom Fe doped ZrO2 emerged as the most promising catalyst for OER. This finding offers a valuable perspective and reference for experimental researchers to design cost-effective catalysts for the industrial-scale OER production. [ABSTRACT FROM AUTHOR]

Graphene/metal oxide (rGO/MOx) heterostructures hold great promise for energy storage, yet a full understanding of their synthesis remains elusive. Herein, a general, efficient, and scalable synthesis strategy is designed for the preparation of various rGO/MOx heterostructure materials featuring robust interfacial interactions. The heterogeneous nucleation growth mechanism of metal oxides on graphene is elucidated through ex situ characterization and theoretical simulation. The surface of graphene oxide (GO) is enriched with reactive oxygen‐containing functional groups, serving as potent nucleation sites that facilitate the rapid and heterogeneous nucleation of MOx grains. Simultaneously, a stable interface (C−O−M bond) is in situ formed between graphene and adsorbed metal ions during heat treatment, producing rGO/MOx heterostructure materials. Notably, the resultant rGO/CoO heterostructure material is employed as an anode and LiCoO2 as a cathode to assemble a soft packaging quasi‐solid‐state battery, which has demonstrated an impressive energy density of 341.4 Wh kg−1 and maintains outstanding capacity retention at 93.4% after 300 cycles at a 1C current. These findings provide valuable insights into the preparation and potential applications of rGO/MOx heterostructure materials for energy storage. [ABSTRACT FROM AUTHOR]

Over the years, metal oxides have been leveraged to create several intriguing novel antibacterial active materials such that while finding the ways and means to increase efficiency, rare earth elements are found to have often served as potential optical dopants such that an optimistic en route to achieve the same, branched Sm‐doped CuO nano‐lanceolates were synthesized employing a wet chemical approach. The samples were then annealed at three distinct temperatures, which were fixed to 300 °C, 400 °C, and 500 °C. The nano‐lanceolates have crystallized in the monoclinic phase, according to the XRD analysis. The SEM image of Sm‐doped CuO captured at a magnification of 2 μm reveals a branched morphology, with multiple nano‐lanceolates stacked in a stem. TEM image reveals that the width of a typical nano‐lanceolate attached to a stem and its tip are found to be 87 nm and 212 nm, respectively and the obtained EDS data validate that elements including Cu, Sm, and O are present in the doped sample. The UV‐visible spectra of the annealed samples indicate that the sample annealed at 300 °C (1.43 eV) has a larger band gap than the other samples. The sample that was annealed at 400 °C has endured defect emissions that are more intense than those of other samples, according to the obtained PL spectra. In addition to these fascinating findings, the samples annealed at 300 °C, 400 °C and 500 °C exhibit a zone of inhibition of 23 mm & 24 mm, 11 mm & 12 mm and 12 mm & 11 mm, respectively for the two tested bacterial strains which authenticate that the 300 °C annealed Sm‐doped CuO nano‐lanceolate deactivates the two pathogenic bacteria more effectively compared to the other samples. As a consequence, the Sm‐doped CuO nano‐lanceolates at 300 °C could potentially be an effective alternative for antibacterial materials, particularly in biomedical applications [ABSTRACT FROM AUTHOR]