Activating peroxymonosulfate (PMS) with metal-free carbon catalysts represents a promising and environmentally benign strategy for water purification, which has recently attracted widespread research interest. Nevertheless, practical implementation in real waters remains challenged by matrix complexity and limited accessible active sites. Herein, a three-dimensional hierarchical phosphorus-doped porous carbon (3DHPC) was synthesized from renewable glucose, where manganese nitrate was used to construct mesopores, while sodium hypophosphite served as the phosphorus source and assisted in regulating the hierarchical pore structure. The 3DHPC-0.2 delivered a micro-/mesoporous architecture and showed rapid BPA degradation via PMS activation, achieving 99.5

Crystal violet (CV), a prohibited dye frequently misused in aquaculture, presents notable toxicological concerns and continues to threaten food safety. In this work, a fast and highly sensitive strategy was developed for the determination of CV residues in fish matrices by coupling surface-enhanced Raman spectroscopy (SERS) with a tailored machine learning approach. Silver nanocubes were employed as the SERS-active platform, offering abundant electromagnetic enhancement sites that amplify spectral signals. To achieve accurate quantification, three regression algorithms—Partial Least Squares (PLS), Support Vector Machine regression (SVM), and Random Forest (RF)—were comparatively evaluated. The findings show that PLS performance is limited by its linear assumptions and susceptibility to overfitting (R2 = 0.9529), whereas SVM demonstrates robustness mainly at lower concentration levels in the presence of noise. In contrast, the RF model exhibits the most reliable predictive capability, yielding a test-set R2 of 0.9926 alongside a low mean absolute error of 0.0046 ppm. Further interpretation of feature contributions indicates that RF effectively integrates spectral information across a wide frequency range, from low-frequency structural vibrations to high-frequency stretching modes of conjugated systems, thereby maintaining prediction stability even under conditions approaching signal saturation.

Excessive phosphate discharge into aquatic systems drives eutrophication while depleting finite phosphorus resources. To address this dual challenge, a magnetic calcium/ferric hydroxide composite was developed via co-precipitation for efficient phosphate recovery. The optimized magnetic calcium/ferric hydroxide composite (Ca:Fe = 3:1) integrates CaFe-layered double hydroxide and Ca(OH)(2), achieving a phosphate uptake capacity of 224.2 mg/g. Pseudo-second-order kinetics confirmed the chemisorption mechanism, and the Freundlich isotherm revealed a multilayer adsorption behavior. Thermodynamic analysis confirmed the exothermic nature of the process. The composite performed robustly across pH 2-12, in the presence of competing anions, and in real water matrices. Mechanism studies identified pH-dependent pathways: electrostatic attraction and ligand exchange on amorphous akageneite under pH< 6; hydroxyapatite precipitation and ligand exchange with ferrihydrite at pH >= 6. LDH facilitated uptake via ion exchange and self-assembly under high phosphate concentrations (>= 600 mg/L) and strongly alkaline conditions (pH >= 12). The material maintained its magnetic properties, enabling easy separation and reuse over five cycles with > 90 % performance retention. This work presents a high-capacity, recyclable adsorbent that supports both eutrophication control and resource recovery, while offering mechanistic insights for designing multifunctional metal-based adsorbents.

In this study, Ag@NU-66 core-shell composites were synthesized by coating silver nanospheres with the metal organic framework (MOF)-UiO-66-NH₂ (Zr) using a straightforward hydrothermal technique. The resulting composite combines excellent stability, high enrichment capacity, and photocatalytic properties. As a SERS substrate, Ag@NU-66 effectively detected a range of harmful contaminants, with detection limits as low as 10-9 M, 10-8 M, and 10-9 M for methylene blue, rhodamine 6G, and thiram, respectively. In addition, Ag@NU-66 exhibited efficient removal of these pollutants under simulated solar light photocatalysis. The dual functionality of the composite can be attributed to the enhanced electromagnetic field created by the plasmonic properties of silver nanospheres, along with improved charge transfer facilitated by the adsorption capabilities of UiO-66-NH₂. Furthermore, the Ag@NU-66 composites demonstrated superior stability compared to bare silver nanospheres in various solvents, even in oxidative conditions containing halide ions. These findings support the potential development of Ag@NU-66-based sensing and pollutant removal systems for environmental applications.

Flexible electronic sensors have garnered significant interest in applications spanning epidermal electronics, soft robotics, and next-generation wearable systems. This work reports a novel fabrication strategy for a breathable, strain-sensitive conductive hydrogel (PCH) that integrates high electrical conductivity, superior mechanical compliance, and enhanced wearing comfort. The hydrogel matrix comprised a conductive double-network structure formed from polyvinyl alcohol (PVA), carboxymethyl chitosan (CMC), hydroxypropyl cellulose (HPC), and a hydrophilic nanocomposite of hydroxylated carbon nanotubes and nanocellulose (OHCNT-CNF), with NaCl serving as an ionic dopant. A precisely controlled, perforated, and continuously tunable porous architecture was engineered using AgCl as a templating agent. PVA constituted the primary network, endowing the hydrogel with elasticity, flexibility, and soft tactile properties. CMC and HPC jointly formed the secondary dynamic network, significantly enhancing toughness, tensile strength, and structural stability under cyclic deformation. Moreover, the abundant surface hydroxyl groups on CMC and HPC fibers promoted preferential ion accumulation within water-rich porous domains, thereby facilitating efficient ionic conduction pathways. Synergistic contributions from the OHCNT-CNF nanocomposites and NaCl further elevated bulk conductivity. The PCH porous hydrogel demonstrated excellent conductivity (6.38 S/m), breathability (15.34 mg cm-2 h-1) and high sensing sensitivity (GF = 2.66). It enabled highly sensitive, real-time monitoring of a broad range of human motions and physiological signals, including electromyography (EMG) and electrocardiography (ECG). By virtue of its sensitive monitoring of EMG, the PCH hydrogel was applied to human-machine interaction systems, realizing real-time, high-precision manipulation of a robotic arm and virtual characters in electronic games.

Hydrogel dressings are widely employed in wound repair due to their superior ability to absorb exudate, maintain a moist environment, and promote wound healing. However, conventional hydrogels often fail to adequately address the multifaceted biological processes involved in wound healing. In this study, a self-healing and injectable hydrogel (OKGM-AG-Allicin) composed of oxidized konjac glucomannan (OKGM), aminated gelatin (AG), and natural antibiotic allicin was prepared via Schiff base reaction as a wound dressing. This hydrogel exhibited remarkable swelling (1236 ± 122.2%) and degradation (94.56%) properties, along with sustained and controlled release of allicin. It significantly promoted the proliferation and migration of human skin fibroblasts (HSF), while markedly suppressing the expression of pro-inflammatory cytokines IL-1β and IL-6, achieving an inhibition rate of 99.99%. Furthermore, the hydrogel exhibited potent antibacterial activity, with a 99.99% inhibition rate against Staphylococcus aureus. In an infected rat wound model, the hydrogel showed excellent biocompatibility and therapeutic efficacy, achieving a wound closure rate of 95.87% within 14 days and facilitating well-organized tissue remodeling. The implantation of hydrogel resulted in accelerated wound healing and enhanced tissue regeneration. The findings indicate that the OKGM-AG-Allicin hydrogel dressing holds promising applications in advanced wound care.

Surface-enhanced Raman scattering (SERS) has emerged as a highly effective technique for ultra-sensitive chemical analysis, enabling the detection of trace amounts of organic pollutants (OPs) through detailed spectral information. In this study, we propose a simple in situ deposition method to fabricate a hybrid SERS substrate combining graphite-phase carbon nitride (g-C3N4) with Ag nanoparticles (Ag NPs). The size and distribution of the Ag NPs were finely tuned by adjusting the mass of AgNO3. The optimized g-C3N4/Ag composite exhibited excellent performance for SERS detecting methylene blue with a detection limit of as low as 2.81 x 10-9 M. The enhanced SERS activity can be attributed to the plasmonic effect of the densely packed Ag NPs and the adsorption properties of g-C3N4. Furthermore, the substrate demonstrated excellent reproducibility, good uniformity and long-term stability. Additionally, when integrated with machine learning using a Random Forest algorithm, the system accurately identified four similar OPs-methylene blue, crystal violet, rhodamine 6 G, and thiram -with a classification accuracy of above 99.5 %. This work highlights the potential of combining SERS with machine learning for effective environmental and food safety monitoring.

In this study, a novel magnetic composite, Ag@Fe3O4/UiO-66-NH2 (Ag@FUN), was developed by incorporating a porous metal-organic framework (MOF), UiO-66-NH2, which offers selective enrichment capabilities and facilitates solar-driven photoreduction of Cr(VI). The surface coverage of silver nanoparticles on Ag@FUN was precisely controlled by adjusting the AgNO3 feed concentration, enabling tunable SERS sensitivity. SERS measurements revealed that the Ag@FUN composites exhibited strong signal intensity for Cr(VI), along with excellent signal reproducibility and storage stability. These composites were capable of detecting Cr(VI) at concentrations of as low as 7.81 × 10-8 M in tap water and 8.89 × 10-8 M in pond water. The remarkable SERS performance is attributed to the porous MOF structure, which enriches Cr(VI) via Zr-O coordination, electrostatic interactions, and pore-filling effects. Importantly, under simulated sunlight, Ag@FUN effectively reduced Cr(VI) within 70 min. The composites also demonstrated outstanding recyclability, retaining their SERS sensitivity and photocatalytic efficiency through five consecutive "detection-reduction" cycles. Overall, the Ag@FUN composites developed in this work exhibit high SERS sensitivity and robust photocatalytic activity, offering significant potential for environmental monitoring and ecological remediation.

In surface-enhanced Raman scattering (SERS) measurements, the creation of "hot spots" and the effective concentration of analytes in these areas are crucial for enhancing detection sensitivity. In this work, a novel composite with highly SERS activity, Ag nanospheres decorated Ag nanostar/ZIF-8 composite (Ag NS/ZIF-8/Ag) was achieved via first coating the Ag nanostars with the metal-organic framework ZIF-8, known for its strong molecular adsorption capabilities, followed by the electrostatic self-assembly of Ag nanospheres. The composites produce numerous hotspots due to the abundant plasmonic nanogaps, including the interstitial space between the Ag nanostar and Ag nanospheres, as well as internanogaps between neighboring Ag nanospheres, resulting in outstanding SERS performance. It was successfully applied for the quantitative and simultaneous detection of diquat and thiram in fruit juice, achieving detection limits of 5.0 × 10-8 mol/L and 1 × 10-8 mol/L, respectively, with recovery rates ranging from 86.6 % to 118.4 %. Notably, under UV light exposure, the composite was able to degrade pesticides efficiently within 80 min. Additionally, its reusability was demonstrated by sustaining strong SERS activity over five continuous detection cycles. These results emphasize the capability of Ag NS/ZIF-8/Ag composites for sensitive pesticide detection via SERS.

Dendritic fibrous nanomaterials play an important role in the adsorption of heavy metals. The introduction of fluorescent groups on the dendritic fibrous nanosilica (DFNS) will endow it with the ability to recognize and adsorb heavy metals. In this work, DFNS was first prepared as starting materials. Then, it was chemically modified with vinyltriethoxysilane (VTES) to make its surface rich in C=C double bonds. At the same time, the RAFT reagent (Br-CTA-CH=CH2) containing -Br and C=C double bond was synthesized. In addition, fluorescent monomers Naph-CH=CH2 and BT-CH=CH2 were synthesized by introducing C=C double bonds on naphthalimide and benzothiazole, respectively. Then, Naph-CH=CH2, BT-CH=CH2, and Br-CTA-CH=CH2 were subjected to RAFT polymerization to obtain fluorescent hyperbranched polymers (FL-HBPs) containing Br groups. Finally, FL-HBPs were loaded onto the surface of CH2=CH-DFNS by Heck reaction to obtain organic-inorganic composite microspheres (FL-HBP-DFNS). The microspheres can sensitively identify and efficiently separate Pb2+/Hg+. The probe exhibits fluorescence enhancement of the Pb2+/Hg+ ions. The limit of detection (LOD) reaches 1.04 nM and 2.46 nM, respectively. Moreover, the adsorption efficiency of Pb2+ reaches 99.7%, and the adsorption capacity is 157.5 mg/g. Therefore, FL-HBP-DFNS can play effective roles in the identification and removal of heavy metals.

Small-molecule biomarkers hold significant pathological relevance, yet their direct quantitative analysis in complex clinical samples remains challenging. In this work, we present a molecular sieving and analyte enrichment-based surface-enhanced Raman spectroscopy (SERS) biosensor for the selective and quantitative detection of trace levels of uric acid and adenine in serum. The biosensor is constructed by in-situ growth of silver nanoflowers on a polydimethylsiloxane (PDMS) substrate, followed by the self-assembly of a porous metal--organic framework (MOF) layer. This design synergistically integrates MOF-assisted molecular enrichment and size-selective sieving with highly sensitive SERS detection, enabled by the abundant electromagnetic "hotspots" generated from the three-dimensional anisotropic architecture of the plasmonic Ag nanoflowers. Employing this "molecular enrichment and sieving" strategy, the biosensor achieves an impressive limit of detection of 10(-8) M, along with excellent quantitative performance (R-2 > 0.988) for both uric acid and adenine in serum-without requiring biomacromolecules (proteins and nucleic acids) removal pretreatment. Moreover, the biosensor exhibits outstanding storage stability, reproducibility, and reusability, maintaining high SERS performance over five detection cycles under UV light. In summary, we have developed a robust and integrated SERS platform that enables quantitative, sensitive, and size-selective detection of small-molecule biomarkers in complex biological environments.

In this research, we fabricated an innovative NiO/CN/Ag composite through the straightforward electrostatic assembly of Ag nanoparticles and g-C3N4 sheets onto NiO nanoflowers. This composite enables both surface enhanced Raman spectroscopy (SERS) detection and photo-degradation of pesticides. The results reveal NiO/CN/ Ag can quantitatively detect thiram (TRM) and diquat dibromide (DQDB) in water, with a limit of detection (LOD) of 10-9 M, and also exhibit outstanding photo-degradation efficiency, exceeding 95 % for TRM and DQDB within 90 min under simulated sunlight. Significantly, after the organic reagent (citric acid) on NiO/CN/Ag was completely removed through simulated solar irradiation, the signal-to-noise ratios of SERS spectra on NiO/CN/ Ag were enhanced, achieving LODs of 10- 8 M for TRM and DQDB in different fruit juices and dried flower teas. Additionally, the composite demonstrate impressive recyclability, maintaining robust SERS signals and high degradation rates even after five cycles of "detection-degradation" processes.

In this study, we demonstrated an efficient solar photocatalyst, g-C3N4 modified hollow Ag/ZrO2 core-shell composites (Ag/hZrO2/CN) using polymethylacrylic acid (PMAA) nanospheres as sacrificial template. The optimized Ag/hZrO2/CN catalyst demonstrated substantial photocatalytic performance, achieving 97.6 % degradation of methylene blue (MB) and 99.5 % degradation of thiram (TRM) within 90 min under simulated sunlight using a 500 W Xe lamp. The improved property is likely attributed to the synergistic effect among three constituents and the effective segregation of photogenerated electron-hole pairs in ZrO2, g-C3N4 and Ag NPs, as confirmed by photocurrent and EIS analysis. Based on free radical scavenging studies (e-, h+, center dot OH and center dot O2- ), the mechanism underlying the boosted photocatalytic activity was suggested. Moreover, Ag/hZrO2/CN presented excellent surface enhanced Raman scattering activity, achieving quantitative sensing of MB and TRM with limits of detection of 5 x 10- 8 and 10-6 mol/L, respectively, and a favorable linear correlation between SERS intensities and logarithmic concentration (R2 >= 0.97). Additionally, Ag/hZrO2/CN accomplished recyclable SERS detection of MB and TRM through stimulated sunlight irradiation, which is significant for the recyclable SERS detecting through fast sunlight-powered procedure.

A sensitive and stable substrate is crucial in Raman spectroscopic techniques for the effective detection of environmental contaminants. In this study, a novel core-shell composite, Ag@UiO-66, was developed by coating Ag nanospheres with a porous metal-organic framework (MOF), UiO-66-NH2. This composite combines high stability with selective enrichment capabilities for Cr(VI). Leveraging the unique properties of UiO-66-NH2, such as its porosity, abundant amine groups, and Zr nodes, Ag@UiO-66 effectively enriches Cr(VI) through pore-filling, electrostatic interactions, and Zr-O coordination. Direct analysis of water samples spiked with Cr(VI) showed detection limits of 6.53 x 10-8 M in pond water and 7.52 x 10-8 M in lake water. The composite also exhibited excellent signal uniformity and reproducibility, with a low relative standard deviation of 6.78% across 30 batches. Additionally, it demonstrated outstanding recyclability under simulated sunlight irradiation due to the solar photocatalytic properties of UiO-66-NH2. Ag@UiO-66 also showed superior stability compared to pristine Ag nanospheres when exposed to strong acids, bases, or oxidative environments (e.g., 1% H2O2 solution). Overall, Ag@UiO-66 shows great potential as a reliable substrate for the trace detection of chemical analytes via SERS.

Surface-enhanced Raman spectroscopy (SERS) has been perceived as a valuable tool in ensuring food safety due to its rapid and intuitive nature. In this study, we demonstrate a novel cellulose-ZIF-8-noble metal nanostructure as a SERS substrate for the analysis of pesticide residues in food. Cellulose nanocrystal (CNC) acting as a scaffold, we systematically integrate ZIF-8 and Ag nanoparticles to fabricate tailored necklace-like CNC/ZIF-8/Ag core/ shell nanostructures. SERS analysis reveals the CNC/ZIF-8/Ag presents an high enhancement factor of 6.39 x 104, a low limit of detection (LOD) of 10- 9 mol/L, and a relative standard deviation of 10.24 % across 20 substrate batches for 4-mercaptobenzoic acid, underscoring its robust sensitivity and reproducibility. Moreover, its utility extends to the quantification of diquat dibromide (DQ) in standard solutions and green tea leaves, showcasing LODs of 6.61 x 10-9 mol/L and 6.76 x 10- 8 mol/L, respectively, thereby exhibiting promising capabilities for ultra-sensitive pesticide detection in food. The exceptional SERS property can be ascribed to the enriching properties of the porous ZIF-8 nanostructures. Significantly, when exposed to UV light, the CNC/ZIF-8/ Ag nanostructures efficiently degrade DQ within 60 min. Furthermore, their practical reusability under UV light is proved by high SERS performance across five detection cycles. These results emphasize the immense potential of CNC/ZIF-8/Ag in SERS-based trace pesticide detection.

Exploring robust, sensitive and reliable surface-enhanced Raman spectroscopy (SERS) substrates largely depends on creating a high density of hot spots. Hererin, we present the fabrication of a unique core-satellite composite, consisting of sandwich Ag/MOF/Ag nanoshells, achieved by constructing two layers of dense Ag satellites with a MOF interlayer on PMAA nanospheres. These innovative sandwich Ag/MOF/Ag nanoshells create two distinct types of plasmonic nanogaps: the interstitial space between the Ag nanoshell layers and the internanogaps between adjacent Ag satellites. This structure significantly increases the number of hot spots compared to traditional core-monolayer metal satellites, leading to enhanced SERS activity. As expected, the composites exhibit an impressive enhancement factor of 3.85 x 106 and a low detection limit (LOD) of 10-9 mol/L for methylene blue. The SERS sensing performance is further validated by successfully quantifying ciprofloxacin (CIP) and paraquat (PQ) in real milk samples with LODs of 3.28 x 10-7mol/L for CIP and 1.71 x 10-8 mol/L for PQ, demonstrating strong potential for ultra-sensitive detection of hazardous pollutants in foods.

In this work, we proposed a straightforward self-assembly and in-situ deposition protocol to construct Cu2O/g-C3N4/Ag composites, which demonstrated peroxidase-like attribute and exceptional SERS activity. These composites proved to be an effective SERS analysis tool for detecting organic fungicides like malachite green (MG) and crystal violet (CV). Remarkably, they achieved detection limits as low as 10−9 M in DI water as well as fish pond water, and exhibited a strong linear correlation between logarithmic concentrations and SERS intensities (R2 ≥ 0.97). Beyond that, with the aid of hydrogen peroxide (H2O2), the peroxidase-like Cu2O/g-C3N4/Ag composites rapidly degraded MG and CV molecules within just 5 min. Furthermore, their practical reusability based on the peroxidase-like reaction was proved by high SERS performance across 5 detection cycles. These results emphasize the immense potential of Cu2O/g-C3N4/Ag in SERS-based trace fungicide detection and suggest future applications in ecological restoration through peroxidase-like reactions.

Hollow hZrO 2 /g-C 3 N 4 photocatalysts were developed to efficiently degrade MB and CIP under simulated sunlight irradiation and the mechanism was investigated.

Hydrogel-based wearable sensing devices are attractive and have broad application prospects on motion intention recognition and health monitoring. The research on the aspect of their wearable comfort and the improvement of breathability is essential. In this paper, a breathable porous hydrogel film was prepared using a template method combined with the inverse Hofmeister effect. Different from conventional hydrogels that utilize the Hofmeister effect by using lyophilic ions for toughening, our approach involved the reverse application of the Hofmeister effect, the use of chaotropic ions, which induced a loosening effect within the hydrogel interior, thereby achieving a more uniform pore distribution. The prepared hydrogel film has excellent mechanical properties (elongation at break of 404%, tensile strength of 173 kPa), air permeability (9.96 mgcm(-2)h(-1)), and sensitivity (GF = 4.41). The film is used as a wearable sensor with high sensitivity and accuracy to monitor human finger, wrist, and large joint movements, human electrophysiological signals [electromyogram (EMG) and electrocardiogram (ECG)], small changes in vocal cord vibration, and manipulation of electronic devices for gaming. This work provides an approach for the preparation of breathable hydrogel films as wearable sensors.

Developing sensitive, reliable, and robust surface-enhanced Raman spectroscopy (SERS) substrates relies heavily on fabricating a substantial number of hot spots. In this study, we present a straightforward method for creating Ag@PEI/Ag core-satellite nanocomposites. Large Ag nanospheres serve as the cores, and smaller Ag nanoparticles are electrostatically assembled around them through the introduction of polyethyleneimine (PEI). This assembly process generates numerous hot spots not only between two Ag satellites but also between the inner Ag core and Ag satellites, thanks to the sub-nm PEI interlayer. The nanocomposites exhibit great potential for SERS analysis, enabling effective sensing of various organic pollutants, such as thiram and ciprofloxacin, using a portable Raman spectrometer. Notably, these nanocomposites obtain an exceptional detection limit of as low as 10−8 M for them, which falls below the safety level set by the United States Environmental Protection Agency. Additionally, the substrates demonstrate excellent uniformity, reproducibility and storing stability. Consequently, the Ag@PEI/Ag core-satellite nanocomposites hold great promise as efficient SERS platforms for reliable and highly sensitive monitoring of food safety and environmental analysis.