High-purity alumina (HPA) is a cornerstone material in advanced energy and electronic technologies necessary for the global energy transition. Traditionally, HPA is routinely studied using bulk analytical techniques, which overlook nanoscale inhomogeneities. However, as industrial demand shifts toward increasingly higher purity standards, a fundamental understanding of the structural and chemical nanoscale characteristics of HPA becomes essential. In this study, electron microscopy and atom probe tomography are used to reveal that crystallographic defect structures within HPA act as major sinks for bulk impurities. These impurities are preferentially accumulated via dislocation-mediated diffusion. These findings challenge the conventional homogeneous view of pure bulk materials and show that HPA can be chemically and structurally inhomogeneous at the nanoscale level. The results highlight the critical role of nanoscale characterization of high-end materials and reveal new opportunities to develop innovative pathways for precision design and manufacturing of next-generation high-performance materials.

This study investigates the hydrogen-induced stress cracking (HISC) behaviour of additively manufactured Nickel Alloy 625 (NA625) produced by Laser-Based Direct Energy Deposition (DED-LB625), with particular emphasis on the role of oxide features within the microstructure. DED-LB625 exhibited reduced sensitivity to hydrogen exposure compared with wrought NA625 (W625), demonstrated by a smaller reduction in ultimate tensile strength and improved ductility under hydrogen-charging conditions. Hydrogen desorption measurements revealed a lower mobile hydrogen content in the additively manufactured material, which is indicated in ToF-SIMS and TDS analysis, with this effect attributed to hydrogen trapping at (Nb,Si) rich oxides. Crack propagation was found to preferentially follow sub-grain cellular structures enriched with Laves phase, as demonstrated by TEM, whereas cracks interacting with oxide features showed evidence of blunting and local arrest. These findings highlight the potential for DED-based additive manufacturing to enhance hydrogen tolerance in NA625, supporting its application in hydrogen-containing Oil & Gas environments.

Solar-driven interfacial evaporation (SDIE) represents a sustainable pathway for the co-production of freshwater and electricity, offering a promising solution to global water scarcity and energy deficits. However, the development of low-cost, easily fabricated, highly efficient, and salt-resistant water-electricity cogeneration systems remains a significant challenge. Herein, we fabricate a robust and cost-effective 3D solar evaporator (3D-CSC/ SA@CF) by integrating corn straw-derived carbon (CSC), discarded cigarette filters (CF), and sodium alginate (SA) hydrogel. In this configuration, the CF scaffold serves as a hydrophilic, quasi-aligned porous substrate for rapid water transport, while the CSC layer functions as an efficient broadband solar absorber, endowing the evaporator with a high light absorption of 97.15 %. Benefiting from its abundant hydrophilic groups and rationally designed porous structure, the evaporation enthalpy is significantly reduced to 851 J g- 1-far below that of pure water. As a result, the evaporator achieves an evaporation rate of 4.52 kg m- 2 h- 1 under one-sun irradiation (1 kW m- 2, AM 1.5G), with a corresponding solar-to-vapor efficiency of 97.01 %. The system also exhibits remarkable salt-rejection performance, maintaining a stable evaporation rate of 3.22 kg m- 2 h- 1 in 20 wt% NaCl brine without salt accumulation, and effectively removes heavy metal ions, organic dyes, and antibiotics from simulated wastewater. Furthermore, we construct an integrated thermoelectric cogeneration system based on the evaporator, which delivers a maximum output power density of 307.1 mW m- 2 under 1 sun illumination. This work not only demonstrates a sustainable waste-to-resource strategy but also provides a feasible and scalable approach to multifunctional hydro-energy cogeneration, highlighting its potential for practical applications in remote and resource-limited regions.

Electroforming of metal-oxide-metal memristors is generally attributed to the creation of oxygen-vacancy filaments within the oxide, with noble metal electrodes such as Pt and Au remaining chemically inert. Here, we demonstrate that electroforming and subsequent operation of Pt/NbOx/Nb2O5/Pt devices can induce an unexpected and highly correlated redistribution of both oxygen and platinum. Time-of-flight secondary ion mass spectrometry reveals a filamentary pathway characterized by micrometer-scale oxygen enrichment extending from the Nb2O5 layer through NbOx and deep into the Pt top electrode. Surprisingly, this is accompanied by the formation of a Pt-rich filament penetrating the oxide stack along the same filamentary path. Finite-element and lumped-element modelling show that current-controlled negative-differential-resistance operation produces localized Joule heating and high-frequency thermal cycling, which strongly enhances oxygen migration and enables thermally assisted Pt diffusion along vacancy-rich pathways. These findings reveal a previously unrecognized metal-ion transport mechanism in NbOx memristors and highlight the critical role of post-forming electrical dynamics in determining filament chemistry, stability, and device reliability.

Nanofabrication using focused ion beam and reactive ion etching techniques was conducted on single-crystal aluminium substrates with three crystallographic orientations: (111), (100), and (110). Among these, the (110) surface exhibited the highest etch rate of 15±2 nm/min and the lowest surface roughness of 2±0.5 nm using reactive ion etching. This enhanced understanding of how crystal orientation affects surface quality is expected to contribute significantly to the advancement of low-loss diffractive optical elements across the infrared to extreme ultraviolet spectral ranges. This is the first time that etching on single-crystal aluminium has been investigated with focused ion beam and reactive ion etching, providing references for potential optical device fabrication.

Geopolymers are an emerging class of binding materials used in sustainable cements, concretes, and composites. However, despite growing research, the lack of standardised processes and stability analyses for formulating activator solutions - a crucial component of geopolymer systems - remains a barrier to quality control and research advancement. This study presents an experimentally validated energy balance with thermodynamic phenomenon mathematically modelled for synthesising consistent geopolymer activator solutions. The model's general applicability enables dynamic assessments of user-specified systems, offering stability metrics for quality control in laboratory and industrial settings. Fundamentally, the mathematical model can be used towards batching optimisation under user-defined conditions where dissolution of geopolymer precursors can be maximised via solution preparation and batching optimisation. The model results quantify experimentally validated temperature dynamics, thermodynamic stability, and process design/batching optimisation, challenging traditional practices in the literature that rely on undefined equilibration periods. Key findings demonstrate that stable, ready-to-use activator solutions can be achieved in as little as 1 minute, compared to the typically used 24-hour batching periods. This research paves the way towards standardised activator solution preparation and supports the development of Standard Operating Procedures (SOPs) for geopolymer synthesis, promoting consistency and scalability in geopolymer technology.

As an emerging memory device, memristor shows great potential in neuromorphic computing applications due to its advantage of low power consumption. This review paper focuses on the application of low-power-based memristors in various aspects. The concept and structure of memristor devices are introduced. The selection of functional materials for low-power memristors is discussed, including ion transport materials, phase change materials, magnetoresistive materials, and ferroelectric materials. Two common types of memristor arrays, 1T1R and 1S1R crossbar arrays are introduced, and physical diagrams of edge computing memristor chips are discussed in detail. Potential applications of low-power memristors in advanced multi-value storage, digital logic gates, and analogue neuromorphic computing are summarized. Furthermore, the future challenges and outlook of neuromorphic computing based on memristor are deeply discussed.

Elevating the cut-off voltage of LiCoO2 (LCO) cathode in lithium-ion batteries (LIBs) enhances capacity but increases structural instability. While surface coatings are used to mitigate structural degradation at high voltages, conventional full coverage coatings often fail to withstand the cyclic mechanical stress, resulting in crack formation and performance decay. Here, a multifunctional CeO2 nanoparticle (NP) pinning structure is designed as a surface coating on LCO (LCO@CeO2) to enable stable operation at a high cut-off voltage of 4.6 V (vs Li/Li+). This surface pinning architecture balances structural integrity with minimal inactive material usage. The CeO2 NPs are strategically anchored to the LCO surface, creating a pinning structure that accommodates volume changes and suppresses fracture formation in the cathode. Moreover, the CeO2-mediated fast Li+ transport pathways are established, improving high-rate capability. The interspersed CeO2 NPs also act as oxygen reservoirs, stabilizing reversible (O2)3- species during high-voltage oxygen anionic redox reactions. Consequently, the optimized LCO@CeO2 cathode achieves a capacity retention of 85.3% after 500 cycles at 1C and a high-rate capacity of 124.8 mAh g-1 at 10C. This CeO2 NP pinning structure offers a novel practical strategy for designing durable high-voltage layered cathodes.

Trace elements in sulfides are commonly used to determine the physicochemical conditions of ore deposit formation. The thermodynamic models underpinning these studies rely on the assumption that trace elements are incorporated into the mineral's crystal structure, however recent atomic-scale investigations suggest that this assumption may be erroneous, especially in metamorphosed environments. Here, in primary undeformed colloform sphalerites from two Pb-Zn deposits in South-China, we study the microstructural, geochemical, and nanoscale distribution of trace elements. Our results show that colloform sphalerite hosts trace elements such as Ge (up to 5671 ppm) and Ga (up to 16307 ppm) in nanoscale polyphase inclusions (mainly 10-20 nm), comprising an aqueous solution and solid phases such as galena and pyrite. These Ge(-Ga) polyphase inclusions are rich in light elements and halogens (H, Li, Na, Cl, K) and heavier metals such as Mn and Pb, accounting for 5 %-78 % of the trace element budget in bulk sphalerite. We propose a model whereby the rapid crystallization of colloform sphalerite favors the preservation of elevated trace element concentrations in nanoscale fluid inclusions (i.e., Ga, Ge, Pb, Mn) that are in apparent thermodynamic disequilibrium with sphalerite. A nucleation mechanism is proposed involving the entrapment of dense liquid composed of an intermediate high-density disordered state under supersaturation conditions. Based on a global geochemical data compilation of colloform sphalerite, we show significant enrichment of Pb in colloform sphalerite and multiple positive correlations between Pb and Ge. This suggests that Pb-Ge-rich nanoscale dense-liquid inclusions may be a prevalent carrier for trace elements observed in colloform sphalerite textures. Similar colloform textures resulting from supersaturated solutions in minerals such as pyrite or quartz may also contain trace element-rich nanoscale inclusions. Presence of these nanoscale inclusions appears to have a minimal effect on the estimated formation conditions derived from sphalerite chemistry (temperature, fS2). This study highlights the value of chemical mapping in revealing temperature variations in sphalerite.

The study of the structure and geochemistry of olivine crystal defects is important but difficult because of their nanometer size and the analytical limitations of most techniques. Laser-assisted atom probe tomography (APT) is capable of sub-nanometer resolution, quantitative geochemical analysis and 3D reconstruction of olivine defects, but optimal analytical conditions and data reconstruction strategies have not been sufficiently studied. Here, we investigate the effect of different laser pulse energy (LPE) and crystal orientations on the quality and reconstruction parameters of APT data using specimens from two San Carlos olivine grains. Our findings show that increased LPE reduces the background noise, percentage of multiple hit events, and applied electric field, as shown by the Mg2+/Mg+ ratio, but increases the peak tails. The major element compositions show inaccuracies under all LPEs but exhibit higher consistency for higher LPEs. We determine that a LPE of 150pJ is the best compromise for optimal data quality in olivine. Using scanning electron microscopy imaging before and after APT analyses, we suggest that the Mg2+/Mg+ ratio can be used as a guide to estimate the electric field parameter and results in more accurate reconstructions.

Lattice oxygen participation mechanism (LOM) can break the conventional adsorption scaling limitations to boost electrocatalysis performance and has been utilized to design promising single-phase oxides that generally show favorable bulk oxygen-ion diffusion capability. In pure-phase materials, bulk oxygen vacancies could act as oxygen-ion diffusion channels, implying rich bulk oxygen vacancies at the interfaces of hybrid-phase composites may further boost LOM. Here, by designing hybrid Co2.5Ru0.5Ox hollow nanotubes with rich two-phase interfaces, we report a phenomenon of interfacial LOM. Such hollow nanotubes (∼10 nm wall thickness), composed of spinel Co3O4-x-rutile RuO2-x interfaces, exhibiting a low overpotential of 430 mV and a long-term stability of 1000 h at 500 mA cm-2 for oxygen-evolving reaction (OER) in near-industrial alkaline solutions (6 M KOH). The constructed anion exchange membrane electrolyzer requires only 1.82 V to achieve a 1 A cm-2. Interfacial Co/Ru atomic interactions trigger Co-O-Ru motifs to undergo self-optimization during OER through oxidizing Co/Ru ions and narrowing bond length to create short synergetic active sites, while interfacial oxygen vacancies act as ion-diffusion pathways. Combined mechanism experiments and computations unravel the exceptional interfacial LOM processes. Additionally, the hollow nanotube structure promotes OH- adsorption, serving as a beneficial driving force for interfacial LOM.

Ni-rich LiNi0.8Mn0.1Co0.1O2 (NCM) cathodes in layered oxide cathodes are attractive for high-energy lithium-ion batteries but suffer from rapid capacity fade and thermal instability at high charge voltages. In this study, we propose an entropy-assisted multi-element doping strategy to mitigate these issues. Specifically, two routes are designed and compared: bulk-like localized high-entropy doping (BHE-NCM) and surface-distributed high-entropy-zone doping (SHE-NCM). The surface entropy-doped NCM cathode delivers enhanced electrochemical performance, including higher capacity retention under 4.5 V cycling and superior rate capability, compared to both bulk-like and pristine counterparts. Comprehensive material characterization reveals that surface-localized doping stabilizes the layered structure with reduced microcrack formation and creates a uniform dopant-rich surface region with improved thermal and electrochemical stability. Overall, entropy-assisted doping at the near surface zone effectively alleviates structural degradation and interface reactions in Ni-rich NCM, enabling improved cycling performance at high voltage. This work highlights the significance of surface entropy engineering as a promising strategy for designing high-voltage cathodes with improved safety and longevity.

This paper presents a study on the molecular beam epitaxial (MBE) growth of Hg0.72Cd0.28Te thin film materials on Cd0.96Zn0.04Te (2 1 1)B substrates, incorporating a 10 nm thick MgTe sacrificial layer for subsequent lift-off. The Hg0.72Cd0.28Te thin films present a full width at half maximum of 31 arc sec for the X-ray diffraction rocking curve and a root-mean-square surface roughness of 1.2 nm. Additionally, this study developed and characterised an epitaxial lift-off process for the HgCdTe epilayers. The HgCdTe epilayers were successfully lifted-off from the substrate by adhering them to a silicon substrate and immersing in deionized water to dissolve the MgTe sacrificial layer. After lift-off, the samples exhibited p-type conduction with a carrier concentration of 2.01x 10(15) cm(-3) and a hall mobility of 1.96x10(2) cm2/V.s at 77 K. Following the epitaxial lift-off process, photoconductors were fabricated on the HgCdTe thin films, which demonstrated a peak responsivity of 1080 V/W and a peak detectivity of 3.3 x 10(10) Jones at 77 K at the wavelength of 5.4 mu m. The minority carrier lifetime was measured to be around 1.15 mu s at 77 K. A scanned imaging system was constructed to assess the infrared imaging performance of the photoconductor. These results were then compared with those of a photoconductor fabricated on HgCdTe thin films without the epitaxial lift-off process, and indicated that the lift-off process has minimal impact on the optoelectronic properties of the thin film and on device performance. These findings validate the feasibility of producing high quality, free-standing HgCdTe thin films for future applications in curved imaging arrays.

Quasi-solid-state lithium metal batteries (QSSLMBs) hold great promise for next-generation energy storage but face major challenges for applications, including air instability of electrolytes, high synthesis cost, and poor interfacial compatibility. Here, La(OH)3-based Li+ conductor Li0.15Sr0.525La0.6(OH)3 (LSLOH) is reported, which is air-stable and cost-effective. LSLOH serves as an ionic conductor exhibiting Li⁺ conductivity of 0.1 mS cm-1 at 30 °C. To improve interfacial transport, LSLOH is incorporated into a polyethylene oxide (PEO)-LiTFSI polymer electrolyte (PL) to form a quasi-solid-state electrolyte (PL-LSLOH). LSLOH provides additional Li⁺ transport channels, while La3+ and Sr2+ interact with TFSI- to promote Li⁺ mobility. Moreover, LSLOH induces the formation of a LiOH and Li2O-rich solid electrolyte interphase, effectively suppressing Li dendrite growth. As a result, the LiNi0.6Co0.1Mn0.3O2 | PL-LSLOH | Li pouch cells achieve 2.2 mAh cm-2 at 0.83 mA cm-2 (with cathode loading of 19 mg cm-2) over 200 cycles with 92.5% initial capacity retention, underscoring the potential for scale-up. For the first time, this work demonstrates La(OH)3-based lithium ionic conductors and electrolyte design that address key barriers to the QSSLMBs.

Geopolymers present a sustainable alternative to conventional binders, however, their commercial viability is hindered by a lack of standardised methods for preparing stabile activator solutions; alkaline feedstocks critical to geopolymer synthesis. This study presents a combined experimental and modelling approach to evaluate the thermochemical stability, solubility constraints, and silica speciation behaviour of sodium silicate-based activators. Using quantitative 29Si NMR analysis, thermodynamic stability and three-dimensional solubility modelling, this research identifies optimal preparation conditions that minimise irreversible precipitation risks and optimises mixing periods. Key findings indicate that higher solution temperatures associated with optimised activator solution preparation were found to enhance thermochemical stability and reactivity, while cooling increased viscosity and the likelihood of unstable solution behaviour, which may necessitate discarding. The order in which feedstocks are combined directly affects whether the solution becomes unstable, with an optimal sequence of water, alkali-hydroxide, soluble silicate found to ensure greater process reliability. A predictive model and accompanying visual tools enable practitioners to assess solution viability and define stability windows by quantifying initial and final/unstable periods and temperatures based on feedstock composition and solution temperature. These results contribute to improved reproducibility and quality control in geopolymer research and represent a step toward developing standard operating procedures for activator solution synthesis.

The application of hardware-based neural networks can be enhanced by integrating sensory neurons and synapses that enable direct input from external stimuli. This work reports direct optical control of an oscillatory neuron based on volatile threshold switching in V3O5. The devices exhibit electroforming-free operation with switching parameters that can be tuned by optical illumination. Using temperature-dependent electrical measurements, conductive atomic force microscopy (C-AFM), in situ thermal imaging, and lumped element modelling, it is shown that the changes in switching parameters, including threshold and hold voltages, arise from overall conductivity increase of the oxide film due to the contribution of both photoconductive and bolometric characteristics of V3O5, which eventually affects the oscillation dynamics. Furthermore, V3O5 is identified as a new bolometric material with a temperature coefficient of resistance (TCR) as high as -4.6% K-1 at 423 K. The utility of these devices is illustrated by demonstrating in-sensor reservoir computing with reduced computational effort and an optical encoding layer for spiking neural network (SNN), respectively, using a simulated array of devices.

Australia is one of the main reserves of rare earth elements phosphate (P-REE) minerals. Phosphate-solubilising bacteria (PSB) are capable of dissolving the phosphate content of such minerals. It has been demonstrated that P-REE leaching efficiency is greater when microorganisms are in direct contact with the ore surface. This study investigated biofilm formation by the PSB Klebsiella aerogenes on the surface of monazite. Initial attachment occurred during the early hours of exposure and was affected by extracellular DNA (eDNA) production, particle size, physico-chemical properties of the surface, total available area for attachment, and inoculation size. K. aerogenes produced eDNA, which provides high attachment-affinity towards the surface of P-REE, hence, playing an important role during initial attachment. Attachment occurred preferentially on larger-sized particles. Analysis of the dynamics of planktonic and sessile equilibrium during initial attachment revealed greater biofilm formation in the presence of monazite compared to a glass surface, in which lowering the initial cell concentration shifted the equilibrium towards a greater sessile population promoting biofilm formation, as did increasing the total available area. Given enough time PSBs colonise the surface of these minerals and form mature biofilms, which cover almost the whole surface. Microscopy analysis of biofilm cross-sections showed a thin-layer structure. Biofilm selectively formed on and around physical imperfections but showed no selectivity towards particular mineralogy.

In this paper, we present a study on the direct growth of Hg0.7Cd0.3Te thin films on layered transparent van der Waals mica (001) substrates through weak interface interaction through molecular beam epitaxy. The preferred orientation for growing Hg0.7Cd0.3Te on mica (001) substrates is found to be the (111) orientation due to a better lattice match between the Hg0.7Cd0.3Te layer and the underlying mica substrate. The influence of growth parameters (mainly temperature and Hg flux) on the material quality of epitaxial Hg0.7Cd0.3Te thin films is studied, and the optimal growth temperature and Hg flux are found to be approximately 190 °C and 4.5 × 10−4 Torr as evidenced by higher crystalline quality and better surface morphology. Hg0.7Cd0.3Te thin films (3.5 µm thick) grown under these optimal growth conditions present a full width at half maximum of 345.6 arc sec for the X-ray diffraction rocking curve and a root-mean-square surface roughness of 6 nm. However, a significant number of microtwin defects are observed using cross-sectional transmission electron microscopy, which leads to a relatively high etch pit density (mid-107 cm−2) in the Hg0.7Cd0.3Te thin films. These findings not only facilitate the growth of HgCdTe on mica substrates for fabricating curved IR sensors but also contribute to a better understanding of growth of traditional zinc-blende semiconductors on layered substrates.