Background Conventional surface-enhanced Raman spectroscopy (SERS) methodologies typically depend on prefabricated substrates, which can constrain their utility for rapid, in-situ diagnostics. While nano-inks offer a route toward flexible sensing, their application typically still follows a direct, substrate-based paradigm. Trends toward the miniaturization of Raman spectroscopy and on-site diagnostics necessitate a fundamental rethinking of sensor design, prioritizing minimal sample preparation and direct analysis. Results Gold nanostar (AuNS)-based plasmonic inks are presented as a versatile platform for surface-enhanced Raman scattering (SERS)-based detection of pyocyanin – a key virulence factor of Pseudomonas aeruginosa. Two SERS configurations are explored: a conventional paper-based sensor, used to establish the analytical performance of the AuNSs ink (LOD 15 nM in saliva), and an inverted approach, where the ink is deposited directly onto a medical cotton swab pre-loaded with the sample. The inverted configuration, coupled with a portable Raman spectrometer (785 nm), enables direct, substrate-free detection of pyocyanin with a clinically relevant LOD of 5 μM and requires minimal sample pretreatment. Spike-and-recovery experiments in saliva yielded recoveries of 96–105% (sr ≤ 0.10), confirming the accuracy of the method. The inverted SERS approach on cotton swabs thus offers a practical, rapid, and simple route for point-of-care screening of P. aeruginosa infections, circumventing the need for prefabricated sensors or laboratory equipment. Significance and Novelty By transforming the standard clinical swab into an active SERS substrate, the inverted approach provides a practical, substrate-free, and equipment-light platform for direct pathogen screening at the patient’s bedside. This strategy addresses key barriers to SERS implementation – reliance on prefabricated sensors, complex sample handling, and bulky instrumentation – offering a realistic and scalable solution for non-invasive screening. This approach is particularly significant for the analysis of potentially bio-contaminated surfaces, such as medical instruments or hospital environments, where direct contact with the analyte is hazardous or undesirable.

In this work, Li1.3Al0.3Ti1.7(PO4)3 (LATP) ceramics with a NASICON-type structure were synthesized using three ultrafast high-temperature sintering (UHS) modes: linear, stepwise, and impulse. The effect of the heating profile, sintering temperature, and processing time on the phase composition, microstructure, relative density, and ionic conductivity was systematically investigated. All UHS modes enabled rapid densification of the material while suppressing abnormal grain growth and preserving phase purity. Among the studied modes, the impulse UHS mode yielded the highest relative density and ionic conductivity, reaching 97 % and 3.7 × 10−4 S cm−1, respectively, under optimal conditions. Additionally, LATP ceramics produced via impulse UHS exhibit enhanced stability during long-term galvanostatic cycling in symmetric Li||Li cells compared to samples prepared by conventional muffle furnace sintering. These results demonstrate the high effectiveness of the impulse UHS approach for fabricating dense and highly lithium-conductive LATP ceramic electrolytes.

The density and microstructure of ceramic solid-state electrolytes (SSEs) critically determine their transport properties and the electrochemical performance of solid-state lithium batteries (SSLBs). The NASICON-type solidstate electrolytes including Li1 +xAlxTi2-x(PO4)3 (LATP) and Li1+xAlxGe2-x(PO4)3 (LAGP) electrolytes usually generate abnormal grain growth or pore coalescence during sintering, respectively. Both of structural drawbacks will dramatically decrease ionic transport of lithium (Li) ions and resistance to lithium protrusion into electrolyte. In this work, we repoured a fancy strategy to design NASICON solid-state electrolyte by introducing Apollonian bimodal packing to significantly enhance green-body densification of electrolyte. Nanoscale LATP and microscale LAGP particles are rationally combined and sintered with an optimized co-firing protocol to obtain the new class of Li1+xAlxGeyTiz(PO4)3 (LAGTP) SSEs. This LAGTP electrolyte has a single-phase structure with suppressed abnormal grain growth and pore coalescence, showing enhanced Li+ transport pathways and a reduced migration barrier of 0.314 eV. The resulting SSE delivers a high ionic conductivity of 6.4 & times; 10-4 S cm- 1, low porosity, a high relative density of 95.3%, and an improved elastic modulus of 134 GPa. Electrochemical evaluation of solid-state battery demonstrates outstanding cycling stability and effective lithium protrusion suppression, highlighting critical role of enhanced electrochemical-mechanical properties of electrolyte in highperformance SSLBs.

Rechargeable aqueous zinc-ion batteries (ZIBs) have received significant attention because of their high safety and low cost. MnO2 as a cathode material hampers the application of ZIBs due to its structural instability and dissolution during the operation of the battery. In this work, gallium (Ga) is successfully doped into the crystal structure of alpha-MnO2, which effectively stabilizes the tunneling structure of MnO2 and improves the conductivity of the bulk material. The Ga doping reduces the coordination numbers of Mn-O, Mn-Mnedge, and Mn-Mncorner shells to 4.4, 4.0, and 0.3, respectively, promoting the formation of Mn and O vacancies in the Ga@MnO2 material. Electrochemical charge/discharge processes show that Ga doping remarkably improves the transport rates of Zn2+ and H+, whereas the reaction products have an enhanced reversibility of deposition/dissolution. Therefore, the Ga@MnO2 cathode provides a capacity up to 352.7 mAh g-1 at 0.1 A g-1 and maintains a discharge capacity of 125.2 mAh g-1 even after 1500 cycles at 2 A g-1. Our work demonstrates that Ga doping is a facile strategy for enhancing the electrochemical performance of alpha-MnO2 by modifying the local structure, paving a way for further application of ZIBs. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (ZIBs) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)MnO2(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic) (Ga) (sic)(sic)(sic)alpha-MnO2(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)MnO2(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).Ga(sic)(sic)(sic)Mn-O,Mn-Mnedge(sic)Mn-Mncorner(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)4.4,4.0(sic)0.3, (sic)(sic)(sic)Ga@MnO2(sic)(sic)(sic)Mn(sic)O(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), Ga(sic)(sic)(sic)(sic)(sic)(sic)(sic)Zn2+(sic)H+(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)/(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic), Ga@MnO2(sic)(sic)(sic)0.1 A g-1(sic)(sic)(sic)(sic)(sic)352.7 mAh g-1(sic)(sic)(sic), (sic)(sic)(sic)2 A g-1(sic)(sic)(sic)1500(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)125.2 mAh g-1(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)alpha-MnO2(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).

The rapid and sensitive detection of trace contaminants in food, particularly pesticide residues and migrating packaging additives, remains a critical challenge in food safety monitoring. This has prompted the development of an innovative flexible surface-enhanced Raman scattering (SERS) substrate that overcomes conventional limitations, such as poor enhancement performance, insufficient stability, and narrow spectral response ranges. To address these challenges, this work proposes the strategic assembly of gold nanostars (AuNSs) and gold nanoparticles (AuNPs) on expanded graphite (EG)-modified filter paper to engineer a sandwich-structured SERSactive platform with exceptional broad-spectrum response capabilities, achieving optimal plasmonic coupling. At a 4:1 AuNSs/AuNPs ratio, the substrate generates high-density 'hot spots' with a remarkable enhancement factor (4.7 & times; 106 for R6G) and detection limits reaching 10-9 M, coupled with outstanding thermal stability (20-100 degrees C) and long-term performance (30 days), while demonstrating practical detection of thiram residues (0.24 ppm, 20 & times; below US safety limits) and DMSO (1 % v/v), thereby providing fundamental insights into hybrid plasmonic nanostructures while delivering a field-deployable solution for comprehensive food safety monitoring from farm to table.

NASICON-type solid-state electrolytes (SSEs) offer high ionic conductivity, ambient stability, and low cost, making them promising candidates for next-generation solid-state lithium batteries (SSLBs). However, their practical application is hindered by chemical incompatibility and poor interfacial contact with lithium (Li) metal anodes. Here, we report an effective interfacial design to address these challenges. A three-dimensional (3D) electron/ion mixed-conducting bilayer interface is fabricated to achieve intimate coupling between the Li1.3Al0.3Ti1.7(PO4)3 (LATP) SSE and Li anode, while simultaneously serving as a Li host to form an in-situ 3D anode architecture. This interlayer-built 3D anode seamlessly integrates with the SSE, providing chemical protection for LATP, regulating uniform Li deposition, and achieving a low interfacial resistance of similar to 7 X cm2. Consequently, Li||Li cells exhibit ultralow overpotential of similar to 10 mV at 0.1 mA cm-2 for more than 1400 hand stable cycling at 1 mA cm-2. Li||LiFePO4 full cells deliver excellent cyclability (95.5% at 0.2 C, 95.0% at 0.6 C after 100 cycles) with high Coulombic efficiency of 99.9%. Notably, the interlayer suppresses violent LATP-molten Li reactions up to 300 degrees C, while LATP prevents short circuiting, demonstrating exceptional thermal stability. This work establishes a scalable interfacial design strategy for NASICON-type SSEs, advancing the practical deployment of SSLBs. (c) 2026 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Pyridine and its derivatives are highly toxic and strictly regulated class of compounds, making their sensitive monitoring essential for human health and environmental safety. Despite the high sensitivity of surface-enhanced Raman scattering (SERS) for detecting various analytes, analysing volatile compounds remains difficult due to the inability to retain the analyte on noble metal nanoparticle surfaces. Herein, we demonstrate for the first time that SERS enables the sensitive, rapid and simple detection of the toxicant pyridine in gaseous form. We introduce a novel strategy that provides SERS analysis of volatile analytes, thereby expanding the scope of molecules accessible to this method. Trapping pyridine in stable transition metal-pyridine complexes enables shifting the absorption maximum from ultraviolet to the visible spectral range (500-660 nm), which is closer in energy to the plasmon absorption band of the silver nanostructured substrate and the laser energy of the Raman spectrometer. Thus, we observed sensitivity down to 5.7 mg/m3 using benchtop Raman spectrometer with a 638 nm laser wavelength, achieving detection limits below the permissible exposure limit for gaseous pyridine, due to the additional resonant enhancement. The immobilisation of transition metal ions in a porous chitosan layer on the plasmonic surface efficiently captures and retains pyridine vapours near the surface. This approach demonstrates broad potential for the trace-level monitoring of a wide class of volatile analytes by SERS.

Zinc oxide (ZnO) nanostructures with deposited silver (Ag) nanoparticles (NPs) exhibit exceptional opportunities for highly sensitive molecular diagnostics by means of the surface-enhanced Raman spectroscopy(SERS). Here we use the well known method of the hydrothermal synthesis of arrays of ZnO nanorods (NRs), followed with deposition of Ag-NPs by facile photochemical reduction under UV-light illumination to obtain ZnO-NRs/Ag-NPs hybrid structures with superior SERS activity. SERS spectra of a probe analyte, i.e. Rhodamine R6G molecules absorbed in an optimized ZnO-NRs/Ag-NPs structures, are detected in a wide range of the analyte concentration from 10-6to 10-14M. Numerical simulations of the light scattering in ZnO-NRs/Ag-NPs structures allow us to show that the wedge-like morphology of ZnO-NRs plays a crucial role in the 3D electromagnetic enhancement of the SERS signal, which can be as high as 3•108for the lowest analyte concentration. The revealed high SERS activity of the obtained ZnO/Ag hybrid nanostructures together with the simplicity of their preparation open new prospects for their application in analytical chemistry, sensorics and photonics.

Abnormal grain growth and pore coarsening during sintering are common challenges in ceramic solid-state electrolytes (SSEs). These microstructural defects cause volume changes, crack formation, structural degradation, and ultimately battery failure during operation. Herein, we propose a sintering strategy using a composite powder of glass and ceramic phases to fabricate NASICON-type Li1.3Al0.3Ti1.7(PO4)(3) (LATP) electrolyte with high density, high elastic modulus, and excellent ionic conductivity for enhanced solid-state battery performance. By incorporating glass nanoparticles into the LATP submicron matrix and applying a two-step sintering method, the viscous flow generated by glass initially promotes effective densification of green body pellet. Later its crystallization creates internal stress constraints, which suppresses abnormal grain growth and pore coarsening, ensuring a uniform grain size distribution. The resulting SSE, prepared with a glass/ceramic weight ratio of 5 %/95 %, achieves a mechanical strength of 125 GPa, a relative density of 95.7 %, and an ionic conductivity of 7.3 x 10(-4) S cm(-1). The Li||LATP||Li symmetric cell exhibits stable cycling for over 500 h at 0.5 mA cm(-2), while the Li||LATP||LFP full cell delivers stable performance for >100 cycles, retaining 95.5 % of its capacity at 0.2C.

Surface-enhanced Raman spectroscopy is a powerful analytical technique for the determination of analytes with the advantages of sensitivity, portability, and simplicity, able to provide structural information for the identification of compounds. However, when it comes to the analysis of complex samples, matrix components may interfere with the analyte quantification. To overcome this shortcoming, a number of approaches have been proposed, such as extraction techniques. Among them, the coupling of chromatography with surface-enhanced Raman spectroscopy seems to be promising. It allows combining the advantages of both techniques, i.e., high efficiency of chromatographic separation and high sensitivity of surface enhanced Raman scattering detection, and makes possible simultaneous quantification of multiple analytes. The review summarizes the latest achievements in the combination of these techniques.

MXenes, a class of 2D materials that have emerged recently, are known for their unique properties and broad applicability. They are traditionally synthesized from MAX phases by etching A-group atoms, usually Al. Here, the controlled transformation of residual aluminum is demonstrated, as both MAX-phase component and pervasive impurity in MXene synthesis, into a functional diagnostic asset. Through laser irradiation, Al is photooxidized in situ, forming embedded Al2O3:Cr3(+) centers with ruby line luminescence with a peak width of about 1 nm by laser irradiation of individual grains of Cr2AlC. The luminescence emerges due to Al oxidation with Cr doping. It is also demonstrated that the ruby luminescence is an unexpectedly universal phenomenon which occurs even in Cr-free MAX-phases and MXenes, owing to the incomplete Al etching and slight Cr doping of natural origin. Discovered sensitivity of ruby luminescence intensity to residual Al enables rapid, minimally destructive, and spatially resolved control of etching quality, essential for the industrial maturation of MXenes. Furthermore, the capacity to locally generate integrated optical probes opens new pathways for in operando diagnostics in MXene-based devices.

The solid-state electrolytes address the safety concerns of lithium-ion batteries associated with the commercial liquid electrolyte due to potential leakage of flammable organic solvents, but their insufficient mass transport results in capacity drop at higher rates (>2C) and hinders high-power applications. Composite gel-polymer electrolytes (CGPEs) offer the flexibility and processability of polymers alongside the mechanical, thermal, and electrochemical advantages of inorganic fillers. Our study employs mechanical and electrochemical continuum modeling to predict the optimal size of ceramic filler in CGPEs, revealing that nanosized Li1.4Al0.4Ti1.6(PO4)(3) (nano-LATP) particles significantly enhance the strength and reduce ohmic losses during fast-rate cycling. The developed sol-polymer method allows to produce high purity nano-LATP with a particle size of 50 nm in 30 min, an order of magnitude faster than conventional methods. The nano-LATP was incorporated into poly(ethylene oxide)/poly(vinylidene fluoride) matrix to form a composite separator, which was then impregnated with liquid electrolyte to produce CGPEs. Li||CGPE||Li symmetric cells sustained without voltage hysteresis for over 250 h at 2 mA cm(-2) and 3 mAh cm(-2) during Li stripping/plating test, while LTO||CGPE||NMC811 full cells demonstrate high capacity retention of 85 % at discharge rate of 4C over 500 cycles, outperforming cells with commercial separator. This approach offers a promising route to high-power, safe lithium-ion batteries via advanced CGPEs.

The plasmonic sensors based on silver nanoparticles are limited in application due to their relatively fast degradation in the ambient atmosphere. The technology of ion-beam modification for the creation of monocrystalline silver nanoparticles (NPs) with stable plasmonic properties will expand the application of silver nanostructures. In the present study, highly-stable monocrystalline NPs were formed on the basis of a thin silver film by low-energy ion irradiation. Combined with lithography, this technique allows the creation of nanoparticle ensembles in variant forms. The characterization of the nanoparticles formed by ion-beam modification showed long-term outstanding for Ag nanoparticles stability of their plasmonic properties due to their monocrystalline structure. According to optical spectroscopy data, the reliable plasmonic properties in the ambient atmosphere are preserved for up to 39 days. The mapping of crystal violet dye via surface-enhanced Raman spectroscopy (SERS) revealed a strong amplification factor sustaining at least thrice as long as the one of similarly sized polycrystalline silver NPs formed by annealing. The plasmonic properties sustain more than a month of storage in the ambient atmosphere. Thus, ion-beam modification of silver film makes it possible to fabricate NPs with stable plasmonic properties and form clusters of NPs for sensor technology and SERS applications.

A novel phthalocyanine-based hybrid nanofilm is for the first time successfully applied as an oxidative platform for surface enhanced Raman spectroscopy (SERS) sensing to fine-resolve Raman-inactive compounds. The hybrid is formed by self-assembly of zinc(II) 2,3,9,10,16,17,23,24-Octa[(3 ',5 '-dicarboxy)-phenoxy]phthalocyaninate (ZnPc*) with the solid-supported monolayer of graphene oxide (GO) mediated by zinc acetate metal cluster. Atomic force microscopy, UV-vis and fluorescence spectroscopies confirm that this simple coordination motive in combination with molecular structure of ZnPc* prevents contact quenching of the light-excited triplet state through aromatic stacking with GO particles. Fluorescence probing with Sensor Green and terephthalic acid as specific indicators of active oxygen intermediates shows that the hybrid nanofilm initiates selective singlet oxygen generation under visible light. Direct one-electron oxidation of tetramethylbenzidine (TMB) (1.0x10-7 m) on the hybrid surface in the presence of 100 nm silver nanoparticles as plasmonic hot-spots under 450-640-nm light irradiation yields well-resolved resonance Raman spectrum of the oxidized form TMB+1. Using these hybrid nanofilms as visible light platforms for redox reaction of target analytes without additional oxidizing agents, the range of Raman-detectable compounds can be significantly expanded through a rapid ultrasensitive SERS screening of substances currently considered Raman-inactive.

Solid-state batteries with lithium metal anode have been accepted extensively as the competitive option to fulfill the upping requirement for safe and efficient energy devices. Nevertheless, its wide-ranging application has been impeded by the failure of solid-state electrolyte (SSE) induced by development of lithium (Li) filament. Based on the nature of polycrystalline ceramic SSE with varying grain size and boundary strength, the constitutive equation coupled with electrochemical kinetics was applied to picture the propagation of damage and corresponding disintegration caused by the development of Li filament. Based on the results, we found that the stress generated along with the growth of Li filament spreads away via the opening and sliding of grain boundary. Thus, damage occurs along grain boundaries, of which propagation behavior and damage level are controlled by grain size. Especially, over-refinement and under-refinement of grains of SSE can cause flocculent damage with inordinate damage degree and accelerate the failure time of SSE, respectively. On the other hand, the failure time is powerfully prolongated through strengthening the grain boundary of SSE. Eventually, grain size of 0.2 μm and tensile strength of grain boundary of 0.8-time-of-grain are posted as the threshold to realize the postponed failure of NASICON-based SSE. Inspiringly, electro-chemo-mechanical model in this contribution is generally applicable to other type of ceramic SSE to reveal the failure process and provide the design guideline, fostering the improvement of solid-state batteries.

The exceptional optical, electrical, and mechanical capabilities of layered transition metal carbides, nitrides, and carbonitrides, called MXenes, revolutionized materials science. Among them, Ti3C2 received the most attention owing to the developed synthesis and processing methods, high conductivity, and pronounced plasmonic response. The latter, however, remains controversial with the open question of whether the peak around 800 nm has plasmonic or interband transition origin. To address this issue, we combine spectroscopic ellipsometry and transmittance results with first -principle computations. Their combination reveals that although Ti3C2 is a metal, its optical response becomes plasmonic (Re epsilon < 0) above 1415 nm, in contrast to the previous understanding. In addition to fundamental significance, this dual dielectric/plasmonic optical response opens a path for theranostic applications, as we demonstrated on the example of Ti3C2 nanospheres. Thus, our study revisits broadband (300-3300 nm) optical constants of Ti3C2 and broadens its application scope in photonics. (c) 2023 Optica Publishing Group

MXene are promising layered materials that find application as catalysts, sensors, elements of energy-storage systems. They also attract attention due to the possibility of detecting relatively low concentrations of substances using via SERS (surface-enhanced Raman scattering) effect. In this paper, SERS sensors based on commercially available three-component MXene (double-transition-metal MXene) Mo2TiC2-Ox are presented. It is shown that the detection limit of rhodamine 6G using SERS sensors is 10–8 M, which is an order of magnitude higher than the results previously obtained for SERS sensors based on Mo2TiC2Tx. The structure of Mo2TiC2-Ox is analyzed using scanning and transmission electron microscopy, energy-dispersive spectroscopy and Raman spectroscopy. The dynamics of the change in the detection limit of rhodamine 6G were studied using SERS sensors based on Mo2TiC2-Ox. The data analysis allows us to estimate the contribution of the metal components of the residual precursor to the SERS activity of Mo2TiC2-Ox, as well as to identify the degradation pathways of the SERS properties of the MXene. The results are important for understanding the relationship between the SERS activity and the structural properties of MXenes, as well as for assessing the potential of MXene application in the field of SERS sensorics.

A new preparation technique of Li1.3Al0.3Ti1.7(PO4)3 (LATP) ceramics is focused on optimisation of weight fractions of LATP glass additives into green ceramic powder followed by enhanced two-step sintering to improve key parameters of relative density and ionic conductivity of LATP solid-state electrolyte (SSE) pellets. The LATP SSE has been obtained with the relative density and ionic conductivity of (96.3±0.2)% and (8.0±0.2)×10-4S/cm, respectively, after pre-annealing at 570°C for 6h and sintering at 900°C for 6h of mixed glass and ceramic powders with an optimal weight ratio of 5%/95%. Notably, the Li||LATP||Li symmetric cell using such LATP SSE could maintain voltage stability for 300h, and the Li||LATP||NCM111 full cell exhibits good cycling performance over 100 cycles with capacity above 100mAh/g (capacity retention of 79.1%). The proposed simple technique seems to be effective to improve the relative density and ionic conductivity thus acclerating the development of all-solid-state lithium metal battery.