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Reactive molecular dynamics is used to investigate the oxidation of anisotropic silver nanoparticles (nano-Ag) of various shapes, including sphere, cube, disk, cylinder, triangle, and pyramid. The effect of the nano-Ag initial morphology on their stability and composition during oxidation is quantified. Surface oxidation at 600 K leads to the formation of a core–shell structure for all nano-Ag shapes. The surface composition of facet orientations of pristine nano-Ag can be correlated with particle stability due to their different surface energies and oxygen reactivity. In particular, pyramid and triangular nano-Ag, having a high surface fraction of (110) facets, are more prone to morphological changes upon oxidation and loss of their crystallinity, compared to nanospheres and nanocubes, which exhibit the highest stability among all shapes, attributed to the large fraction of highly coordinated atoms. Spherical and cubic nano-Ag oxidize faster, owing to their large surface fractions of (100) and (111) facets, which are more reactive than (110) ones. Understanding the effect of surface crystal structure and shape of anisotropic nano-Ag can improve the design of superior metal oxide nanomaterials with desired characteristics. [ABSTRACT FROM AUTHOR]

Metal oxide transistors have garnered substantial attention for their potential in low-power electronics, yet challenges remain in achieving both high performance and low operating voltages through solution-based fabrication methods. Optimizing interfacial engineering at the dielectric/semiconductor interface is of utmost importance in the fabrication of high-performance thin film transistors (TFTs). In the present article, a bilayer Ti3C2Tx-MXene/SnO2–semiconductor (Tx stands for surface termination) configuration is used to fabricate a high-performance n-type thin film transistor by using an ion-conducting Li-Al2O3 gate dielectric on a p+-Si substrate, where electrical charges are formed and modulated at the Li-Al2O3/SnO2 interface, and Ti3C2Tx-MXene nanosheets serve as the primary electrical charge channel due to their long lateral size and high mobility. A comparative characterization of two distinct TFTs is conducted, one featuring Ti3C2Tx MXene and SnO2 semiconductor layer and the other with SnO2 only. Notably, the TFT with the Ti3C2Tx MXene layer has shown a significant boost in the carrier mobility (10.6 cm2/V s), leading to remarkable improvements in the on/off ratio (1.3 × 105) and subthreshold swing (194 mV/decade), whereas the SnO2 TFT without the Ti3C2Tx MXene layer shows a mobility of 1.17 cm2/V s with 8.1 × 102 on/off ratio and 387 mV/decade subthreshold swing. This investigation provides a possible way toward the development of high-performance, low-voltage TFT fabrication with the MXene/semiconductor combination. [ABSTRACT FROM AUTHOR]

Non-transition metal oxides, including major minerals of the early Solar System, are known to evaporate decomposing into multiple gas molecules, while maintaining their stoichiometric compositions (dissociative congruent evaporation). Here, we derived the absolute rate of this type of evaporation using the transition state theory. In our modified transition state theory, the activation energy closely corresponds to the average energy of the molecules at the transition state, reflecting the degree of decomposition at the potential energy barrier along the reaction coordinate of evaporation. By comparing the theoretical and experimental evaporation rates for the reaction MgO (s) → Mg (g) + O (g), we found that there is an activation barrier close to the product side (i.e., "late" barrier) where the decomposition is almost achieved. The present theory is advantageous to the Hertz–Knudsen equation, which is essentially formulated as the evaporation rate in equilibrium based on the detailed balance, in that it describes dissociative congruent evaporation as a non-equilibrium process and thus provides the link between the experiments and the reaction dynamics. [ABSTRACT FROM AUTHOR]

Two-terminal structure memristors are the most promising electronic devices that could play a significant role in artificial intelligence applications of the next generation and the post-Moore era. In this work, we fabricated the memristive device by depositing a heterojunction WOx/TiOy functional layer onto an indium tin oxide substrate using magnetron sputtering. The Ag/WOx/TiOy/ITO device exhibits improved memory behavior of bipolar resistive switching (RS) nonvolatile compared to TiOy-based single-layer memristors, enabling it to meet high-density information storage requirements. Moreover, our device exhibited the coexistence of the negative differential resistance effect and the behavior of the RS memory. Through a comprehensive analysis of conductivity on the curve of current–voltage (I–V), a physical model based on the mechanism of space charge-limited current, ohmic conduction, and Schottky emission was suggested to explain the behavior device RS memory. This study's findings demonstrate that including a heterojunction bilayer WOx/TiOy as a functional layer can significantly improve the performance of memristive devices. This advancement expands the potential application of ferroelectric metallic oxide heterojunctions within the field of memristors. [ABSTRACT FROM AUTHOR]

Functional thin films of nanoscale metal pillars in oxide or nitride matrices known as vertically aligned nanocomposite (VAN) have gained much interest owing to their unique strain-coupled and highly anisotropic properties. So far, the deposition of these films has been explored mostly experimentally. In this work, a density functional theory (DFT)-based kinetic Monte Carlo simulation model using Bortz–Kalos–Lebowitz algorithm was developed to understand the growth of VAN films deposited by pulsed laser technique on mismatching substrates. The model has been parameterized and applied to understand the kinetics of growth thin films consisting of Au pillars in CeO2 matrix deposited on SrTiO3 substrates. The effects of pulsed laser deposition (PLD) conditions including the pulse frequency, deposition flux, and substrate temperature were explored. The simulations indicate that the Au pillar size and shape exhibit significant dependence on the PLD conditions. Namely, increasing the temperature increases the average pillar size and lowers the pillar density, and vice versa. In addition, the simulations revealed that increasing the deposition rate results in lowering the average pillar size and increasing the density. Particularly, the DFT results suggest that Au pillar size can be tuned during the initial growth of the first monolayer due to the significantly low activation barrier. Our analysis showed that the relationship between the average pillar size and pillar density is influenced by the kinetics. Furthermore, autocorrelation analysis showed that pillars self-organize in quasi-ordered patterns at certain windows of the deposition conditions, which is attributed to the complex nature of the chemical interactions in the system, the kinetics, and the deposition parameters. [ABSTRACT FROM AUTHOR]

The immobilization of Re(I) complexes onto metal oxide surfaces presents an elegant strategy to enhance their stability and reusability toward photocatalytic CO2 reduction. In this study, the photocatalytic performance of fac-[ClRe(CO)3(dcbH2)], where dcbH2 = 4,4′-dicarboxylic acid-2,2′-bipyridine, anchored onto the surface of 1%m/m CuO/Nb2O5 was investigated. Following adsorption, the turnover number for CO production (TONCO) in DMF/TEOA increased significantly, from ten in solution to 370 under visible light irradiation, surpassing the TONCO observed for the complex onto pristine Nb2O5 or CuO surfaces. The CuO/Nb2O5 heterostructure allows for efficient electron injection by the Re(I) center, promoting efficient charge separation. At same time CuO clusters introduce a new absorption band above 550 nm that contributes for the photoreduction of the reaction intermediates, leading to a more efficient CO evolution and minimization of side reactions. [ABSTRACT FROM AUTHOR]

We have attained low leakage current, low interfacial traps, and low border traps by effectively passivating both p- and n-In0.53Ga0.47As (InGaAs) surfaces using the same gate dielectrics of ultra-high-vacuum deposited Al2O3/Y2O3. Gate leakage currents below 2 × 10−7 A/cm2 at gate fields of ±4 MV/cm were obtained after 800 °C rapid thermal annealing, demonstrating the intactness of the interface and heterostructure. Negligibly small frequency dispersions in the capacitance–voltage (C–V) characteristics of p- and n-type metal-oxide-semiconductor capacitors (MOSCAPs) were obtained from accumulation, flatband, to depletion as measured from 300 K to 77 K, indicative of low border and interfacial trap density; the C–V frequency dispersions in the accumulation region are 1.5%/dec (300 K) and 0.19%/dec (77 K) for p-InGaAs, and 2.2%/dec (300 K) and 0.97%/dec (77 K) for n-InGaAs. Very low interfacial trap densities (Dit's) of (1.7–3.2) × 1011 eV−1cm−2 and (6.7–8.5) × 1010 eV−1cm−2, as extracted from the conductance method, were achieved on p- and n-InGaAs MOSCAPs, respectively. [ABSTRACT FROM AUTHOR]

Narrow bandgap p-type semiconducting metal oxide nanowires (NWs), such as copper oxide (CuO), have gained significant attention for their potential in the development of electrical nano-devices. Tailoring the mechanical and electrical properties of CuO NWs is crucial for optimizing their functionality in specific applications. In this study, we employ nanosecond laser irradiation to precisely modify the properties of individual CuO NWs by inducing point and line defects, including oxygen vacancies and dislocations. Through controlled laser irradiation, we observe a gradual enhancement in the concentration of oxygen vacancies within CuO NWs until reaching a saturation point. The accumulation of vacancies leads to a substantial residual stress, resulting in lattice distortion and misfit. This high residual stress serves as a catalyst for the nucleation of dislocations, subsequently leading to a meaningful enhancement in plasticity. Remarkably, the density of dislocations demonstrates a strong correlation with the duration of laser irradiation. Prolonged irradiation leads to a thermally activated restoration process, where the dislocation configuration transitions from a random distribution to ordered dislocation loops. Mechanical characterization tests indicate that pristine CuO NWs exhibit brittleness, while laser irradiation renders them ductile with improved plasticity. Furthermore, the laser processing of CuO NWs demonstrates an enhancement in their electrical conductivity and optical absorbance. [ABSTRACT FROM AUTHOR]

The holy grail of achieving efficient operation of infrared (IR) rectennas continues to be the realization of a high performance rectifier. In this paper, we have fabricated metal–insulator–metal (MIM) diodes based on TiO2, ZnO, and NiO thin films using shadow mask evaporation, photolithography, and sputtering. The electron affinities of oxides have been measured by a combination of variable angle spectroscopic ellipsometry and x-ray photoelectron spectroscopy, as well as deduction from the extraction of metal/oxide barrier heights of Fowler–Nordheim tunneling plots. Our results confirm a low value for the electron affinity of NiOx of ∼2.1–2.5 eV, which correlates with the high zero-bias dynamic resistance (RD0) of ∼500 kΩ of an associated MIM diode. These values render NiOx to be unsuitable for use in a rectenna device. Better performance has been observed from diodes based on TiO2 and ZnOx films. The best rectification performance was achieved for a Au/2.6 nm ZnOx/Cr diode, scaled down to 1 μm2 device area, showing a zero-bias dynamic resistance of RD0 = 71 kΩ, zero-bias responsivity β0 = 0.28 A/W, and a coupling efficiency of ηc = 2.4 × 10−5% for rectification at 28.3 THz. The main significance of this study is that it employs a methodology whereby key parameters of the MIM stack are derived from physical measurements, which are then used to assist in the fitting of electrical current–voltage data to produce a reliable appraisal of diode performance in an IR rectenna. [ABSTRACT FROM AUTHOR]

As nanotechnology becomes more important and prevalent, a new reproducible and production-stable synthesis method is needed to meet the demand for the industrial production of nanomaterials. Supercritical fluid (SCF) synthesis is an essential method for the synthesis of metal and metal oxide nanoparticles owing to its fast reaction rate, uniform particle size distribution, high conversion rate, and environmentally friendly nature. This study systematically investigated the crystal nucleation mechanism of metal and metal oxide nanoparticles during synthesis. The effects of reaction material parameters and process parameters on the particle size distribution and conversion rate of nanoproducts were analyzed. Next, the SCF process and the improvement of its core components (mixer and reactor) were studied. Finally, the improvements made to the SCF process were evaluated and future investigation directions are proposed. By presenting a comprehensive overview of SCF technology, this study aims to contribute to the development of a reliable and effective method for the industrial production of nanomaterials. [ABSTRACT FROM AUTHOR]

Currently, most catalysts used for photoconverting carbon dioxide (CO2) typically produce C1 products. Achieving multicarbon (C2+) products, which are highly desirable due to their greater energy density and economic potential, still remains a significant challenge. This difficulty is primarily due to the kinetic hurdles associated with the C–C coupling step in the process. Given this, devising diverse strategies to accelerate C–C coupling for generating multicarbon products is requisite. Herein, we first give a classification of catalysts involved in the photoconversion of CO2 to C2+ fuels. We summarize metallic oxides, metallic sulfides, MXenes, and metal–organic frameworks as catalysts for CO2 photoreduction to C2+ products, attributing their efficacy to the inherent dual active sites facilitating C–C coupling. In addition, we survey covalent organic frameworks, carbon nitrides, metal phosphides, and graphene as cocatalysts for CO2 photoreduction to C2+ products, owing to the incorporated dual active sites that induce C–C coupling. In the end, we provide a brief conclusion and an outlook on designing new photocatalysts, understanding the catalytic mechanisms, and considering the practical application requirements for photoconverting CO2 into multicarbon products. [ABSTRACT FROM AUTHOR]

The design and development of new high-performance catalysts is one of the most important and challenging issues to achieve sustainable chemical and energy production. This Feature Article describes the synthesis of nanostructured metal oxides and phosphates mainly based on earth-abundant metals and their thermocatalytic application to selective oxidation and acid–base reactions. A simple and versatile methodology for the control of nanostructures based on crystalline complex oxides and phosphates with diverse structures and compositions is proposed as another approach to catalyst design. Herein, two unique and verstile methods for the synthesis of metal oxide and phosphate nanostructures are introduced; an amino acid-aided method for metal oxides and phosphates and a precursor crystallization method for porous manganese oxides. Nanomaterials based on perovskite oxides, manganese oxides, and metal phosphates can function as effective heterogeneous catalysts for selective aerobic oxidation, biomass conversion, direct methane conversion, one-pot synthesis, acid–base reactions, and water electrolysis. Furthermore, the structure–activity relationship is clarified based on experimental and computational approaches, and the influence of oxygen vacancy formation, concerted activation of molecules, and the redox/acid–base properties of the outermost surface are discussed. The proposed methodology for nanostructure control would be useful not only for the design and understanding of the complexity of metal oxide catalysts, but also for the development of innovative catalysts. [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]

Two‐dimensional (2D) nonlayered metal compounds with porous structure show broad application prospects in electrochemistry‐related fields due to their abundant active sites, open ions/electrons diffusion channels, and faradaic reactions. However, scalable and universal synthesis of 2D porous compounds still remains challenging. Here, inspired by blowing gum, a metal‐organic gel (MOG) rapid redox transformation (MRRT) strategy is proposed for the mass production of a wide variety of 2D porous metal oxides. Adequate crosslinking degree of MOG precursor and its rapid redox with NO3− are critical for generating gas pressure from interior to exterior, thus blowing the MOG into 2D carbon nanosheets, which further act as self‐sacrifice template for formation of oxides with porous and ultrathin structure. The versatility of this strategy is demonstrated by the fabrication of 39 metal oxides, including 10 transition metal oxides, one II‐main group oxide, two III‐main group oxides, 22 perovskite oxides, four high‐entropy oxides. As an illustrative verification, the 2D transition metal oxides exhibit excellent capacitive deionization (CDI) performance. Moreover, the assembled CDI cell could act as desalting battery to supply electrical energy during electrode regeneration. This MRRT strategy offers opportunities for achieving universal synthesis of 2D porous oxides with nonlayered structures and studying their electrochemistry‐related applications. [ABSTRACT FROM AUTHOR]

The exponential advancement of science and technology, especially within the realm of nanotechnology, has significantly expanded the applications of metal and metal oxide nanoparticles across various industrial sectors, scientific domains, and research institutions. Nickel oxide nanoparticles, in particular, have garnered considerable interest due to their unique characteristics and versatile applications. This paper comprehensively reviews NiO NPs, emphasizing their biological synthesis methods, characterization techniques, and wide‐ranging biomedical applications. These applications include their efficacy against fungal, bacterial, and viral infections, anticancer properties, and potential as innovative therapeutic agents for numerous diseases. Our findings underscore the novelty of NiO NPs in enhancing therapeutic strategies and expanding their biomedical applications, paving the way for innovative medical interventions.The objective of this review is to elucidate a thorough overview of the current research landscape, highlight recent developments, and explore the potential future directions for NiO NPs. [ABSTRACT FROM AUTHOR]

In this work, ruthenium-based catalysts were synthesized via polyol reduction method with different metal oxides as support and caesium as promoter. The samples were characterized through XRD, ICP-OES, nitrogen physisorption and XPS. Then, the catalysts were tested for ammonia synthesis in the range of temperatures 548–673 K and pressures 1–5 MPa. The synthesized catalysts allowed an ammonia production rate approximately four times higher compared with the performances of similar catalytic formulations in literature (tested at same conditions). The best performance were achieved with the Cs–Ru/CeO 2 (1% wt Cs, 5% wt Ru), reaching an ammonia production of nearly 73 mmol h−1∙g cat −1 at 673 K and 5 MPa. As showed by the XPS analysis, the increased Ce3+/Ce4+ ratio led to an enhancement of oxygen vacancies, which favoured the dissociative adsorption of nitrogen, that is the limiting step in the ammonia synthesis reaction. Such high catalytic activity can be ascribed to the beneficial effect of the polyol reduction method for the maximization of the exposure of active sites. [Display omitted] • Ru-catalysts were synthesized via polyol reduction and tested for NH 3 production. • Cs–Ru/CeO 2 enabled a NH 3 production rate of 43 mmol h−1∙g cat −1 at 673 K and 1 MPa. • Increased Ce3+/Ce4+ ratio enhanced oxygen vacancies favouring N 2 adsorption. [ABSTRACT FROM AUTHOR]

Sol–gel‐based solution‐processed metal oxides have emerged as a key fabrication method for applications in thin film transistors both as a semiconducting and a dielectric layer. Here, a low‐temperature, green solvent‐based, non‐toxic, and cost‐effective solution shearing approach for the fabrication of thin aluminum oxide (AlOx) dielectrics is reported. Optimization of sustainability aspects like energy demand, and selection of chemicals used allows to reduce the environmental impact of the life cycle of the resulting product already in the design phase. Using this approach, ultra‐thin, device‐grade AlOx films of 7 nm are coated—the thinnest films to be reported for any solution‐fabrication method. The metal oxide formation is achieved by both thermal annealing and deep ultra‐violet (UV) light exposure techniques, resulting in capacitances of 750 and 600 nF cm−2, respectively. The structural analysis using microscopy and x‐ray spectroscopy techniques confirmed the formation of smooth, ultra‐thin AlOx films. These thin films are employed in organic field‐effect transistors (OFETs) resulting in stable, low hysteresis devices leading to high mobilities (6.1 ± 0.9 cm2 V−1 s−1), near zero threshold voltage (−0.14 ± 0.07 V) and a low subthreshold swing (96 ± 16 mV dec−1), enabling device operation at only ±0.5 V with a good Ion/Ioff ratio (3.7 × 105). [ABSTRACT FROM AUTHOR]

The meticulous design of heterogeneous interfaces presents a promising approach for enhancing the electrocatalytic activity of Cu-based materials in nitrate reduction reactions. Herein, we developed a self-templated metal–organic frameworks transformation strategy to synthesize hollow multi-metallic oxide materials with well-defined interfaces. By utilizing novel hollow Cu–Co bimetallic Prussian blue analogs as precursors, a hollow cage composed of ultra-small CuO/Co3O4 hetero-nanograins was successfully constructed. It was discovered that this structure greatly enhanced the electrocatalytic activity for the conversion of NO3− to NH3, achieving a remarkably high Faradaic efficiency (FE) for NH3 (with a maximum FE of 90.68%) at low overpotential ranges. Furthermore, electrochemical experiments and in situ spectroscopy provided evidence that electrochemically induced reconstruction led to the formation of synergistic sites between Cu and Co3O4. This enabled the sequential reduction of nitrate and nitrite on adjacent metal/metal oxide phases, resulting in the rapid generation of NH3. [ABSTRACT FROM AUTHOR]

The catalytic relevance of different surface functionalities present on hydrotalcite‐derived Mg−Al mixed metal oxides (MgAlO) are investigated in the context of ethanol upgrade to n‐butanol. The catalyst structure and active sites were altered through changes in the Mg/Al ratio and introduction of additional redox metal oxide functionalities. After performing a series of catalytic activity tests, operando FTIR characterization, TGA measurements and in situ active center titration; qualitative and quantitative relationships between catalyst structure and catalytic performance are obtained. We found the Mg−Al mixed metal oxides system can catalyze the ethanol to n‐butanol process through a Guerbet reaction pathway, though the process is kinetically limited. By introducing redox active metal oxides to the catalyst formulation, such as MoO3 or V2O5, this problem can be partially solved, but at a cost of losing a significant fraction of high‐strength basic centers which are the most catalytically relevant function in the system, as they control enolate formation rates leading to the C−C coupling step required for n‐butanol formation. [ABSTRACT FROM AUTHOR]

In this study, nickel supported on various metal oxides were prepared by simple impregnation and the performance for CO2 methanation was tested. The oxide supports were all prepared by thermal decomposition of metal salts to provide comparable oxide properties such as surface area. Among the investigated oxides, nickel supported on CeO2 and Y2O3 showed the highest CO2 conversion of 90% at 320 °C with highest CH4 selectivity of 99%. The order of catalyst activity (XCO2@320°C) was reported: Ni/CeO2 ~ Ni/Y2O3 > > Ni/La2O3 > Ni/ZrO2 > Ni/Al2O3 > Ni/MgO > Ni/CaO > > Ni/MnO. The physicochemical properties of the catalysts were analyzed by TEM, BET, XRD, ICP, H2-TPR, CO2-TPD, H2 chemisorption, TGA, Raman, and XPS. From the characterization results, the catalyst activity was independent to specific surface area of catalyst and crystallite size of Ni. The amount of oxygen vacancies and weak-to-medium basic sites exhibited major roles for enhancing catalyst activity. The CeO2 and Y2O3 as reducible oxide supports not only provided abundant oxygen vacancies / basic sites, but also promoted Ni dispersion with appropriate interaction between metal and support, resulting in higher reducibility at low temperature. The reduction of catalyst at high temperature can significantly improve the performance of Ni supported on non-reducible MgO. However, the Ni/CeO2 and Ni/Y2O3 reduced at high temperature suffered from coalescence of CeO2 and Y2O3, though Ni crystallite sizes are well preserved from sintering. [ABSTRACT FROM AUTHOR]

The utilization of electroplating sludge (ES) to derive metal oxide functional materials is a key strategy, as it enables the recycling of valuable elements, mitigates environmental risks, and aligns with green, low-carbon development strategies. Nevertheless, the development of metal oxide composite functional materials with distinctive structures and properties derived from ES continues to present several challenges. Herein, we synthesized CuFe2O4/MgFe2O4 metal oxide composites from ES by one-step hydrothermal method. As-obtained CuFe2O4/MgFe2O4 metal oxide composites (MMOs) have a unique layered structure, richer mesoporous and microporous structures, activity sites. When evaluated as an adsorbent for Congo red (CR), as-synthesized CuFe2O4/MgFe2O4 with layered structure composite exhibited excellent adsorption capacity (1039.1 mg/g) and reusability (85.55% after five cycles), which was superior to most similar adsorbents reported till date. Such improvement is explored to mainly originate from two respects: the physical adsorption facilitated by the abundant pores formed through the stacking and growth of CuFe2O4 and MgFe2O4, and the chemisorption resulting from surface complexation and hydrogen bonding between the MMOs and CR. This strategy to directly transform ES into functional materials shows great promise both in waste management and preparation of robust adsorbents for wastewater treatment. [ABSTRACT FROM AUTHOR]

Nanoscale dimensional materials represent a captivating area of research in modern technology, owing to their unique properties and vast potential applications. The distinct advantage of nanosized materials lies in their large surface area to volume ratio, which endows them with enhanced stability and significant functional characteristics. Among these, metal oxide nanomaterials have garnered significant attention due to their substantial energy bandgaps and high exciton binding energies, making them suitable for a wide range of applications, including antimicrobial activity and optoelectronics. This review delves into the synthesis methods of various metal oxides, emphasizing the advantages and drawbacks of physical, chemical, and biological approaches. Specifically, it focuses on the synthesis, characterization, and applications of single metal oxide nanoparticles (NPs), such as zinc oxide (ZnO) and silver oxide (Ag2O), as well as binary or composite metal oxides like ZnO/Ag2O nanocomposites. Through this comprehensive literature review, readers will gain insights into the fabrication techniques and explore the intrinsic properties of both single and composite metal oxide NPs, thereby broadening their understanding of these innovative materials and their potential technological impacts. [ABSTRACT FROM AUTHOR]

High‐performance rechargeable aluminum‐sulfur batteries (RASB) have great potential for various applications owing to their high theoretical capacity, abundant sulfur resources, and good safety. Nevertheless, the practical application of RASB still faces several challenges, including the polysulfide shuttle phenomenon and low sulfur utilization efficiency. Here, we first developed a synergistic copper heterogeneous metal oxide MoO2 derived from polymolybdate‐based metal‐organic framework as an efficient catalyst for mitigating polysulfide diffusion. This composite enhances sulfur utilization and electrical conductivity of the cathode. DFT calculations and experimental results reveal the catalyst Cu/MoO2@C not only effectively anchors aluminum polysulfides (AlPSs) to mitigate the shuttle effect, but also significantly promotes the catalytic conversion of AlPSs on the sulfur cathode side during charging and discharging. The unique nanostructure contains abundant electrocatalytic active sites of oxide nanoparticles and Cu clusters, resulting in excellent electrochemical performance. Consequently, the established RASB exhibits an initial capacity of 875 mAh g−1 at 500 mA g−1 and maintains a capacity of 967 mAh g−1 even at a high temperature of 50 °C. [ABSTRACT FROM AUTHOR]

A novel quaternary nanocomposite has been developed using a cost-effective and user-friendly method called electro-spraying. This composite consists of poly(aniline-co-pyrrole), Graphene Oxide (GO), and Iron Oxide (Fe3O4), aimed at achieving improved electrochemical stability and performance. The composite electrodes displayed an impressive specific capacitance of 950 Fg–1 at a current density of 0.5 Ag–1 when tested in a 1 M H2SO4 solution. Furthermore, even after 2000 cycles at a current density of 1 Ag–1, the electrode exhibited an outstanding capacitance retention rate of 91%, showcasing its remarkable stability and long-lasting performance. These exceptional properties can be attributed to the synergistic effects arising from the combination of the conducting polymer, metal oxide, and graphene oxide components within the electrode material. Additionally, significant advancements in other electrochemical properties make this nanocomposite a promising candidate for use as an electrode material in supercapacitors. [ABSTRACT FROM AUTHOR]

Metal oxide aerogels, inorganic cousins of the highly commercialized metalloid oxide silica aerogels, exhibit distinct properties specific to each type. Nevertheless, they share a common challenge with silica aerogels—brittleness and low mechanical strength due to their particulate necklace‐like structure. In contrast, polymer aerogels often boast significantly enhanced mechanical properties thanks to their nanofibrillated networks. To enhance the mechanical properties of metal oxide aerogels, the metal oxide formation with a polymeric nanostructure is micro‐templated. This method transforms the necklace‐like particulate microstructure of metal oxide aerogels (e.g., Al2O3 Cr2O3, and Fe2O3) into a polymer‐like nanobelt structure. Remarkably, even after removing the polymer template through calcination at 600 °C, the nanobelt structure remains intact. These metal oxide nanobelt (MNB) aerogels exhibit exceptional compressibility while retaining their mesoporous structure. As a demonstration, the resulting Al‐MNB aerogel can withstand compression up to 80% strain without fracturing while preserving its porous nanobelt structure and a high specific surface area of 228 m2 g−1 and a pore volume of 0.7 cm3 g−1 after heat treatment at 1300 °C. This work introduces an innovative strategy for creating a distinctive polymer‐like nanobelt microstructure, paving the way for novel applications of metal oxide aerogels with unique structures and enhanced performance. [ABSTRACT FROM AUTHOR]

A new gate driver with metal oxide thin‐film transistors (MO‐TFTs) has been presented for micro‐light‐emitting diode (Micro‐LED) display. The proposed gate driver employing linearly decreasing sweep signal generated module could realize the line‐by‐line pulse width modulation (PWM) driving method, which is valuable for application in high‐resolution Micro‐LED display compared with the conventional driving method employing global sweep signal. A simple Micro‐LED pixel circuit including an inverter module driven by the analog PWM method is employed to demonstrate the feasibility of the proposed gate driver. A 10 × 10 green Micro‐LED display array has been fabricated with MO‐TFTs backplane technology. It is shown that a 10‐μs width pulse and linearly scanning sweep signal can be successfully output. Consequently, the pixel circuit array can be driven properly under analog line‐by‐line PWM driving method. [ABSTRACT FROM AUTHOR]

Hybrid organometal halide perovskites (HP) present exceptional optoelectronic properties, but their poor long‐term stability is a major bottleneck for their commercialization. Herein, a solvent‐free approach to growing single‐crystal organic nanowires (ONW) is presented, along with nanoporous metal oxide scaffolds and HP, to form a core@multishell architecture. The synthesis is carried out under mild vacuum conditions employing thermal evaporation for the metal‐free phthalocyanine (H2Pc) nanowires, which are the core, plasma‐enhanced chemical vapor deposition (PECVD) for the TiO2 shell, and co‐evaporation of lead iodide (PbI2) and methylammonium iodide (CH3NH3I/MAI) for the CH3NH3PbI3 (MAPbI3/MAPI) perovskite shell. A detailed characterization of the nanostructures by electron microscopy, (S)‐TEM, and X‐ray diffraction, XRD, is presented, revealing a different crystallization of the HP depending on the template: while the growth on H2Pc nanowires induces the typical MAPI tetragonal structure, a low‐dimensional phase (LDP) is observed on the 1D‐TiO2 nanotubes. Such a combination yields an unprecedentedly stable photoluminescence emission over 20 h and over 300 h after encapsulation in polymethyl methacrylate (PMMA) under different atmospheres including N2, air, and high moisture levels. Moreover, the unique 1D morphology of the system, together with the high refractive index, allows for a strong waveguiding effect along the HP nanowire length. [ABSTRACT FROM AUTHOR]

2D metal oxides (2DMOs) have recently emerged as a high‐performance class of ultrathin, wide bandgap materials offering exceptional electrical and optical properties for a wide area of device applications in energy, sensing, and display technologies. Liquid metal printing represents a thermodynamically advantageous strategy for synthesizing 2DMOs by a solvent‐free and vacuum‐free scalable method. Here, recent progress in the field of liquid metal printed 2D oxides is reviewed, considering how the physics of Cabrera‐Mott oxidation gives this rapid, low‐temperature process advantages over alternatives such as sol‐gel and nanoparticle processing. The growth, composition, and crystallinity of a burgeoning set of 1–3 nm thick liquid metal printed semiconducting, conducting, and dielectric oxides are analyzed that are uniquely suited for the fabrication of high‐performance flexible electronics. The advantages and limitations of these strategies are considered, highlighting opportunities to amplify the impact of 2DMO through large‐area printing, the design of doped metal alloys, stacking of 2DMO to electrostatically engineer new oxide heterostructures, and implementation of 2D oxide devices for gas sensing, photodetection, and neuromorphic computing. [ABSTRACT FROM AUTHOR]

Polymer specifications' optimization for tailored applications is desirable for enhanced applicability. In this research, we have successfully prepared the PMMA/metal oxide (0.1 wt% CeO2, and TiO2) through a feasible casting method. The implications of the metal oxides incorporation were explored. XRD reveals the successful formation of the composites, with 20 nm crystallite size of both composites. FTIR reinforces the intended composite formation with significant bands allocation. Optical bandgaps for PMMA/CeO2 and PMMA/TiO2 are 2.91 and 3.15 eV for direct transitions, respectively. For indirect transitions, the bandgap is around 3.33 eV for both. Other optical parameters were calculated as real and imaginary dielectric constants. THz displays a linear manner with a somewhat more PMMA fixed band due to the inharmony of intermolecular vibration mode. Dielectric studies manifest polymer loss spectra with multiple non-Debye relaxation progressions β, and γ relaxations alongside MVS polarization for films containing CeO2 or TiO2. The synthesized nanocomposites indicated antibacterial influence against (S. aureus, and B. subtilis) as Gram-positive bacteria, and (E. coli, and K. pneumoniae) as Gram-negative bacteria, (C. albicans) (A. niger) as yeast and Fungi strains. The PC samples show a high impact against Gram-positive bacteria, yeast, and Fungi strains, while PT samples show a high impact against Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Lowering the adverse effects of climate change requires advanced methods to decrease atmospheric levels of carbon dioxide. Here, we review the use of carbonic anhydrase nanobiocatalysts for carbon dioxide sequestration, with emphasis on inorganic, organic, and polymeric nanomaterials. Inorganic nanomaterials include metal and metal oxide, carbon-based, and nonmetallic nanomaterials. Hybrid nanomaterials comprise metal–organic frameworks and nanoflowers. Factors influencing the properties of nanobiocatalysts such as interactions between carbonic anhydrase and the nanoscale support are presented. The immobilization of carbonic anhydrase onto nanomaterials overcomes the limitations associated with its free form, such as short shelf life, challenging separation, and poor reusability. We discuss the potential for large-scale applications. [ABSTRACT FROM AUTHOR]

Composites of carbonaceous materials and the spinel metal oxides have been profoundly analyzed due to their recognized properties, including high capacity, better stability, and good cycle life. The facile synthesis of the binary composite of NiCo2O4-rGO has been done by dextrose-assisted combustion method at temperatures ranging from 300 to 500 °C in a furnace. X-ray diffraction technique has been employed to analyze properties like the crystalline nature and the cubic lattice structure of the samples. The reduction in the restacking of graphene sheets and the agglomeration of NiCo2O4 particles in the composite has been confirmed by Fourier Electron Scanning Electron Microscopy. The Energy-Dispersive X-ray Spectroscopy analysis has been done to confirm the presence of all elements and to find the elemental wt% in the composite. The strengthening of bonds between the elements present in the composite compared to their counterparts is evident from the Fourier Transform Spectroscopy. The Thermogravimetric Analysis confirms the stability of the synthesized composite to withstand higher temperatures. The electrochemical study unveils the specific capacity equal to 400 F g−1 at a 10-mV s−1 scan rate of the synthesized composite. Further, the composite material shows a promising charge–discharge rate and a lower equivalent resistance value affirming that the synthesized composite exhibits good electrochemical activities and can be utilized in energy-storing devices. [ABSTRACT FROM AUTHOR]

The evolution of the modern world necessitates the establishment of diverse industrial sectors, but it is crucial to prioritize sustainability in the process. Many of these industries discharge organic pollutants indiscriminately into aqueous environments, contributing to human and aquatic health consequences. The incorporation of advanced oxidation processes has emerged as a strategy for removing organic contaminants present in wastewater. Sonolytic degradation, a form of advanced oxidation process (AOP), effectively tackles organic pollutants in wastewater, yet it comes with inherent limitations. In addressing limitations, hybrid techniques integrating ultrasound with other AOPs enhance efficiency in wastewater pollutant removal. The combination of ultrasound in conjunction with AOPs, such as heterogeneous approaches like ultrasound combined with metal ions, metal oxides, and photocatalysis, as well as homogeneous methods like ultrasound paired with peroxymonosulfate and persulfate, effectively breaks down organic pollutants. This review emphasizes the efficacy of ultrasound-based hybrid techniques for degrading organic pollutants in aqueous solutions, highlighting their distinct advantages in water treatment. [ABSTRACT FROM AUTHOR]

The fire risk rating assessment of wood was evaluated using fire performance index-VIII, fire growth index-VIII, and fire risk index-IX from previously described Chung's equations. The burning properties of the materials was measured using a cone calorimeter (ISO 5660-1). SnO, SnO2, FeO and Fe2O3 were used as the metal oxides, and sodium silicate was mixed to increase the flame-retardant effect. The fire performance index-VIII was 15.5–139.3 times higher than the uncoated specimen. The fire growth index-VIII was 12–71 times lower than the uncoated specimen. The fire risk index-IX of the coated specimens was 239–9861 times lower than the uncoated specimens. SnOSS was the lowest risk material according to the fire risk rating FRI-IX. A lower oxidation state was a safer material for an initial fire than a higher oxidation state. All specimens showed an improved fire risk compared to uncoated specimens. [ABSTRACT FROM AUTHOR]

Rotary hearth furnaces and rotary kilns are the mainstream methods for large-scale treatment of electric furnace dust (EAFD) in steel companies, but they require a large amount of energy and have low product quality. The roasting conversion–separation technology uses calcium oxide to promote the conversion of zinc–iron spinel in EAFD into zinc oxide and dicalcium ferrite, but adding calcium oxide additionally increases production costs. Converter sludge (OGS) is rich in iron oxides and valuable components such as CaO, CaCO3, ZnFe2O4, etc. The free calcium oxide and calcium carbonate can be used as substitutes for pure calcium oxide. This paper designed a multi-solid waste collaborative reduction roasting process to realize the recovery of zinc and iron elements from OGS and EAFD and explore the feasibility of industrial treatment in rotary hearth furnace. The results show that harmful OGS can be used as the calcium agent in the roasting process. The calcium carbonate in OGS not only improves the conversion of iron oxide into metallic iron, but the decomposed CaO can promote the conversion of zinc–iron spinel in OGS and improve the dezincification effect. Better conditions are: 60% OGS, nC/nO = 1.2, roasting temperature 1150°C, roasting for 25 min; zinc content in the reduction product is 0.21%, and metallization rate is 78.53%, which can be used as a high-quality substitute or coolant for scrap steel raw materials in the steelmaking process. This process can realize green and comprehensive utilization of EAFD and OGS and is expected to achieve industrialization. [ABSTRACT FROM AUTHOR]

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Spent lithium-ion batteries (SBs) are important sources of valuable and critical raw materials. An integration of battery recycling with well-established primary processes for metals production has many advantages. In this work, the recycling of two battery scrap fractions obtained from mechanical pretreatment was integrated with a Ni-slag cleaning process at laboratory scale. Graphite from SBs acted as the main reductant, and the reduction behavior of major and trace elements was investigated as a function of time at 1350 °C. Major CO and CO2 concentrations, as well as minor amounts of SO2, NO2, CH4, and C2H4, were detected in the off-gas line. The evolution of gases took place within the first minutes of the experiments, which indicated that metal oxide reduction reactions as well as decomposition of the organic binders both happened very rapidly. This result is in line with the analytical results obtained for the slag phase, where the most significant metal oxide reduction was observed to take place within the first 5 to 10 minutes of the experiments. The distribution coefficient values for Co and Ni between metal alloy and slag as well as between matte and slag showed no significant differences when battery scrap fractions with different compositions were used. The addition of Ni-concentrate in the starting mixture resulted in increasing recoveries of Ni and Co, as well as improved settling of the matte phase. [ABSTRACT FROM AUTHOR]

A hierarchical structure consisting of In2S3 nanoparticles decorated on ZnO nano arrays is synthesized via a straightforward coupling way. Compared to bare ZnO nano arrays, high photoresponse is measured through the coupling of ZnO nano arrays with In2S3 nanostructures. The hierarchical structure exhibited high-performance UltraViolet (UV) detection with a short recovery time, and its self-powered operation is notable in counterpart of pure In2S3 nanoparticles. It will offer a cost-efficient approach for fabricating high-performance photodetectors utilizing a metal oxide hierarchical structure. [ABSTRACT FROM AUTHOR]

The present research describes one of the processes outlined in the literature, known as Chemical Looping Dry Reforming of Methane, which is currently to gain attraction to produce clean fuels from natural gas using a metal oxide support as a catalyst. This two‐step method offers distinct advantages by physically separating the reaction steps. This spatial separation effectively eliminates undesirable side reactions, leading to highly efficient syngas production with minimal carbon deposition. Crucial to optimizing this process is a deep understanding of the oxygen storage capacity (OSC) of the support (oxygen carrier) that will work in synergy with the supported active phase. Among the candidates, praseodymium stands out due to its favourable redox properties and exceptional OSC characteristics, making it a promising option for cleaner fuel technologies. In particular, this study emphasizes the significant influence of the nature of the active phases (Ni, Co or their bimetallic combinations), with bimetallic phases being the most promising (even without reduction, they can exhibit activity that equals or improves that of the Ru as benchmark), underscoring the fundamental role of catalyst design in achieving optimal performance. The results indicate that these compositions have high activities to generate the products, remaining close to the activity of ruthenium and generating minimal coke deposits in one reaction cycle. [ABSTRACT FROM AUTHOR]

The development of green and environmentally friendly synthesis methods of electrocatalysts is a crucial aspect in decarbonizing energy generation. In this study, eco‐friendly mechanochemical synthesis of perovskite metal oxide‐carbon black composites is proposed using different conditions and additives such as KOH. Furthermore, the optimization of ball milling conditions, including time and rotational speed, is studied. The mechanochemical synthesis in solid‐state conditions without additives produces electrocatalysts that exhibit the highest bifunctional electrochemical activity towards both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Moreover, this synthesis demonstrates a lower Environmental Impact Factor (E‐factor), indicating its greener nature, and due to its simplicity, it has a great potential for scalability. The obtained bifunctional electrocatalysts have been tested in a rechargeable zinc‐air battery (ZAB) for 22 h with similar performance compared to the commercial catalyst (Pt/C) at significantly lower cost. These promising findings are attributed to the enhanced interaction between the perovskite metal oxide and carbon material and the improved dispersion of the perovskite metal oxide on the carbon materials. [ABSTRACT FROM AUTHOR]

Refractory multiprincipal element alloys (RMPEAs) are potential successors to incumbent high-temperature structural alloys, although efforts to improve oxidation resistance with large additions of passivating elements have led to embrittlement. RMPEAs containing group IV and V elements have a balance of properties including moderate ductility, low density, and the necessary formability. We find that oxidation of group IV-V RMPEAs induces hierarchical heterogeneities, ranging from nanoscale interstitial complexes to tertiary phases. This microstructural hierarchy considerably enhances hardness without indentation cracking, with values ranging between 12.1 and 22.6 GPa from the oxide-adjacent metal to the surface oxides, a 3.7 to 6.8× increase over the interstitial-free alloy. Our fundamental understanding of the oxygen influence on phase formation informs future alloy design to enhance oxidation resistance and obtain exceptional hardness while preserving plasticity. [ABSTRACT FROM AUTHOR]

Numerous case studies have shown that nanoparticles (NPs) can help address raw material challenges in biomedical as well as healthcare‐related fields. The NPs derived from metal as well as metal oxide have exhibited remarkable therapeutic potential in clinical research. The strategies for nanomaterials interaction with cells can be employed to demonstrate their significance as well as enhance their optimistic potential in the health as well as medical domain. There have been numerous scientific initiatives to discuss antibiotic resistance as well as the antibacterial properties of metal‐based NPs. Regardless of such advancements; there is still a need to investigate their achievement to address current challenges in this field. Thus, this review looks into the contributions of various types of nanoparticles, as well as potential biological and biomedical applications. According to recent advancements as well as applications, metal oxide, and metal‐based NPs are predicted to play a significant part in the healthcare system. The opportunities, as well as challenges for NP commercial advancement, are linked to improving production with optimized scenarios. [ABSTRACT FROM AUTHOR]

The development of photoelectrochemical tandem cells for water splitting with electrodes entirely based on metal oxides is hindered by the scarcity of stable p-type oxides and the poor stability of oxides in strongly alkaline and, particularly, strongly acidic electrolytes. As a novelty in the context of transition metal oxide photoelectrochemistry, a bias-free tandem cell driven by simulated sunlight and based on a CuCrO2 photocathode and a WO3 photoanode, both unprotected and free of co-catalysts, is demonstrated to split water while working with strongly acidic electrolytes. Importantly, the Faradaic efficiency for H2 evolution for the CuCrO2 electrode is found to be about 90%, among the highest for oxide photoelectrodes in the absence of co-catalysts. The tandem cell shows no apparent degradation in short-to-medium-term experiments. The prospects of using a practical cell based on this configuration are discussed, with an emphasis on the importance of modifying the materials for enhancing light absorption. [ABSTRACT FROM AUTHOR]

Highly active transition metal oxides mesoporous materials have tremendous potential applications in energy storage and catalysis due to their great physicochemical performance. However, the regulation of porous structures still faces many challenges, and the synthesis of mesoporous materials is usually costly and long-time consuming. Herein, using CoO as the example, a strategy based on KOH activation and substitution reaction has been proposed to prepare CoO nanoarrays mesoporous material and improve its electrochemical performance. The CoCO3Co(OH)2 nanoarrays on Ni foam are transformed into a Co(OH)2 nanoarrays with high crystallinity through the substitution reaction in KOH solution. Meanwhile, the activation effect of KOH provides abundant porous structures for etching the nanoarrays. During the annealing process, the high crystallinity of Co(OH)2 effectively alleviates pore collapse, thereby obtaining a CoO nanoarrays mesoporous material with excellent electrochemical performance (denoted as A-CoO@NF). As the positive electrode material for supercapacitors, A-CoO@NF shows a high specific capacity of 775.6 C g−1, far higher than that of CoO@NF (416.5 C g−1). The enhanced electrochemical performance is attributed to its unique mesoporous structures, which positively promote electrolyte permeation and ion diffusion, and the ultrafine nanocrystals and smaller lattice parameters provide numerous edge active sites and enhance the conductivity. The strategy proposed here is expected to become a template-free, low-cost, and efficient preparation route for synthesizing more types of highly active metal oxide mesoporous materials. [ABSTRACT FROM AUTHOR]

Vapor‐deposited inverted perovskite solar cells utilizing self‐assembled monolayer (SAM) as hole transport material have gained significant attention for their high efficiencies and compatibility with silicon/perovskite monolithic tandem devices. However, as a small molecule, the SAM layer suffers low thermal tolerance in comparison with other metal oxide or polymers, rendering poor efficiency in solar device with high‐temperature (> 160 °C) fabricating procedures. In this study, a dual modification approach involving AlOx and F‐doped phenyltrimethylammonium bromide (F‐PTABr) layers is introduced to enhance the buried interface. The AlOx dielectric layer improves the interface contact and prevents the upward diffusion of SAM molecules during the vapor–solid reaction at 170 °C, while the F‐PTABr layer regulates crystal growth and reduces the interfacial defects. As a result, the AlOx/F‐PTABr‐treated perovskite film exhibits a homogeneous, pinhole‐free morphology with improved crystal quality compared to the control films. This leads to a champion power conversion efficiency of 21.53% for the inverted perovskite solar cells. Moreover, the encapsulated devices maintained 90% of the initial efficiency after 600 h of ageing at 85 °C in air, demonstrating promising potential for silicon/perovskite tandem application. [ABSTRACT FROM AUTHOR]

Entropic stabilization of the crystal structure of solids was demonstrated for various systems, starting with metals and continuing with oxides, nitrides, borides, and more complex structures. The influence of additional thermodynamic driving forces sometimes allow to stabilize the material in a crystalline configuration that is unusual for it. In this paper, we focused on the HfZrCeYMgO system, which has shown excellent mechanical properties and a stable crystal structure. We added different concentrations of aluminum oxide, but found that even in significant quantities, it was embedded in the lattice without separating into separate phases. At the same time, we found that the addition of aluminum significantly increases the crystallinity of the coating as well as its mechanical characteristics. We associate the increase in coating crystallinity with a consistent increase in the entropy of mixing in the HfZrCeYMgAlO system. [ABSTRACT FROM AUTHOR]

The current study addresses the chemical coprecipitation approach for synthesizing ZnFe 2 O 4 nanoparticles. Zeta potential analyses were employed to investigate the distribution of particle sizes, polydispersity, and stability within these systems. Rietveld refinement patterns unveiled the effective synthesis of the cubic-structured ZnFe 2 O 4 , devoid of any secondary phases. The outcomes showed the significant impact of the modification approach applied on the colloidal stability of the investigated nanoparticles. UV–Vis spectroscopy confirms that the band gap decreases, and absorption increases with doping. The photoluminescence spectroscopy of the samples revealed empty oxygen spaces and cracks in the structure had formed in the lattice. For electrocatalysis, 10 % Ce doped ZnFe 2 O 4 had an oxygen evolution reaction onset potential of 151 mV vs Ag/AgCl to obtain 10 mA/cm2 current density and the lowest Tafel slope of 35 mV/dec. Therefore, the strategic nanostructuring and design of nanomaterials incorporating earth metal-doped metal oxides are necessary to achieve superior electrochemical performance in their respective energy conversion applications. [ABSTRACT FROM AUTHOR]

Nanocomposite aerogels comprised of TiO2 and metal (Co and Mn) oxides are synthesized via an in situ sol–gel method in this study, and their structural, compositional and electrochemical properties are evaluated for possible applications as electrodes in energy storage devices. The inclusion of metallic oxides into TiO2 aerogels hinder the formation of titania crystalline phases, preserved particle sizes close to their original dimensions and yielded higher specific surface areas compared to pure TiO2 aerogels after heat treatment. High specific surface areas in aerogels positively affect the electrochemical properties, allowing a high electrochemical activity of the electrodes, in addition to intensifying the transport of ions and solvents through the mesoporous network of this material. Evaluation of the electrochemical properties of the aerogel‐based nanocomposites involves galvanostatic charge–discharge, cyclic voltammetry, and impedance spectroscopy. The nanocomposites exhibit enhanced electrochemical properties and stable performance within the range suitable for supercapacitor applications, as indicated by the Ragone chart. Notably, aerogels with higher incorporation of cobalt and manganese oxides in TiO2 aerogels exhibit significantly elevated specific surface areas, reaching 562 and 555 m2 g−1, respectively. These values are notably high for nanocomposites, underscoring the potential of these electroactive materials for electrochemical capacitors. [ABSTRACT FROM AUTHOR]

The evolution of Sb2Se3 heterojunction devices away from CdS electron transport layers (ETL) to wide bandgap metal oxide alternatives is a critical target in the development of this emerging photovoltaic material. Metal oxide ETL/Sb2Se3 device performance has historically been limited by relatively low fill factors, despite offering clear advantages with regards to photocurrent collection. In this study, TiO2 ETLs are fabricated via direct current reactive sputtering and tested in complete Sb2Se3 devices. A strong correlation between TiO2 ETL processing conditions and the Sb2Se3 solar cell device response under forward bias conditions is observed and optimized. Numerical device models support experimental evidence of a spike‐like conduction band offset, which can be mediated, provided a sufficiently high conductivity and low interfacial defect density can be achieved in the TiO2 ETL. Ultimately, a SnO2:F/TiO2/Sb2Se3/P3HT/Au device with the reactively sputtered TiO2 ETL delivers an 8.12% power conversion efficiency (η), the highest TiO2/Sb2Se3 device reported to‐date. This is achieved by a substantial reduction in series resistance, driven by improved crystallinity of the reactively sputtered anatase‐TiO2 ETL, whilst maintaining almost maximum current collection for this device architecture. [ABSTRACT FROM AUTHOR]

As the key component of various energy storage and conversion devices, proton exchange membranes (PEMs) have been attracting significant interest. However, their further development is limited by the high cost of perfluorosulfonic acid polymers and the poor stability of acid‐dopped non‐fluorinated polymers. Recently, a new group of PEMs has been developed by hybridizing polyoxometalates (POMs), a group of super acidic sub‐nanoscale metal oxide clusters, with polymers. POMs can serve simultaneously as both proton sponges and stabilizing agents, and their complexation with polymers can further improve polymers' mechanical performance and processability. Enormous efforts have been focused on studying supramolecular complexation or covalent grafting of POMs with various polymers to optimize PEMs in terms of cost, mechanical properties and stabilities. This concept summarizes recent advances in this emerging field and outlines the design strategies and application perspectives employed for using POM‐polymer hybrid materials as PEMs. [ABSTRACT FROM AUTHOR]

Perovskite oxide semiconductor is unique for its capability to form epitaxial heterostructures with both dielectric and metallic perovskite oxides. The study underscores the potential of perovskite oxides for multi‐layer stacking, a key aspect in advancing semiconductor technology as silicon‐based devices evolve toward 3D stacked structures. Fabrication of the first double‐level double‐gate field‐effect transistors (DL DG‐FETs) is demonstrated, where each layer is epitaxially grown using all‐perovskite oxides. This resulted in improvements in subthreshold swing, current drivability, and field effect mobility. This innovation not only highlights the distinctive potential of perovskite oxides but also provides new avenues for integration with other perovskite oxides on Si for more advanced electronic functions. [ABSTRACT FROM AUTHOR]