This study addresses the challenge of distinguishing between ms-BiVO4 (monoclinic scheelite) and ts-BiVO4 (tetragonal scheelite) using Raman spectroscopy as a complementary technique to powder X-ray diffraction (XRD). The difficulty arises particularly from their similar XRD patterns and the lack of spatial resolution inherent in conventional powder XRD methods. Bismuth(III) vanadate (BiVO4) is an important technological material used in yellow pigments, as well as in solar energy conversion and photocatalytic applications. Its polymorphic nature depends on the synthetic method employed, which affects its performance. Therefore, an accurate identification of the crystalline phases present in a sample is crucial. We demonstrate that the identification of the BiVO4 crystalline phases via Raman spectroscopy is critically dependent on laser power, which may induce an in situ polymorphic transition that can lead to misinterpretations regarding the predominant phase present in the sample. Furthermore, our findings demonstrate the efficacy of confocal Raman spectroscopy in resolving the spatial distribution of ms-BiVO4 and ts-BiVO4 within the same sample, providing an important approach for accurately distinguishing between these crystalline phases.

Supported photocatalysts are essential for overcoming the recovery and post-treatment challenges of water remediation. This study reports the development of an innovative, self-standing 3D-printed photocatalytic scaffold for the degradation of emerging contaminants (ECs) from water. Residue-containing inorganic polymers (IPs) were fabricated using 3D-printing by combining bauxite residue (red mud, RM) and metakaolin. The high iron content in the red mud served as an intrinsic catalyst for the in situ, catalyst-free growth of multi-walled carbon nanotubes (MWCNTs) via thermal chemical vapor deposition (TCVD). Subsequently, a conformal anatase TiO2 thin film was deposited onto the CNT-decorated scaffolds via Atomic Layer Deposition (ALD), resulting in a hierarchical core-shell nanostructure. Characterization revealed a significant 3.7-fold increase in the specific surface area, rising from 55 to 202 m2 g- 1 and a complex bimodal pore architecture. Coupling CNTs and the conformal anatase TiO2 shell enhances charge separation and electron transport, thereby boosting photocatalytic efficiency. The 3D-CNTs/TiO2 composite demonstrated high photocatalytic activity under UV-A irradiation, achieving 92% removal of ciprofloxacin (CIP) from water within 60 min in a continuous-flow process (C0 = 10 mg L- 1, pH 6.5). The degradation followed pseudo-first-order kinetics, with the highest efficiency observed under acidic conditions (pH 3), with roughly complete removal observed at pH 3 within 30 min of irradiation. This superior efficiency in acidic medium is attributed to enhanced electrostatic interactions between the composite and the pollutant. Scavenger assays identified holes and superoxide radicals as the dominant reactive species. Beyond its high stability and reusability over five cycles, the composite proved effective in degrading a complex mixture of four selected ECs. This work offers a sustainable strategy for upcycling industrial residues into robust, reusable photocatalytic materials water remediation.

ABSTRACT Lead halide perovskite nanocrystals (NCs) have attracted considerable attention for solar‐energy applications. However, solar cells integrating these materials raise concerns because of the well‐known toxicity of lead. As such, lead‐free bismuth halide perovskites have been explored as an alternative, although their reported performance remains well below that of lead‐based counterparts. A challenge in this area is the limited availability of non‐conventional chemical strategies for synthesizing nanocrystalline bismuth halide perovskites, particularly when compared with the well‐established methods for preparing lead halide perovskites and when considering implementation under green‐chemistry principles. In this work, we report the first sonochemistry‐assisted synthesis of Cs 3 Bi 2 I 9 perovskite‐like nanocrystals (NCs) using a vegetable oil as a green solvent. The optical, morphological, and structural properties of the resulting nanocrystals were then evaluated before processing into thin films. Although surface‐ligand exchange is crucial for processing perovskite NCs into thin films for solar cells, it has not yet been explored for lead‐free systems. Here, we investigate the thin‐film processing of Cs 3 Bi 2 I 9 NCs prepared in the green solvent and using different antisolvents/purification cycles prior solar‐cell fabrication.

The development of controlled drug delivery systems is an area of growing interest in pharmacology, particularly for drugs with poor solubility and gastrointestinal side effects, such as aceclofenac, a widely used non-steroidal anti-inflammatory drug. This study explores the development of multiparticulate systems based on kappa-carrageenan and sericin for the entrapment and controlled release of aceclofenac. The effect of incorporating cross-linking agents, such as carboxymethylcellulose and proanthocyanidin, on the structure and release profile of the formulations was investigated. The particles were successfully synthesized by ionotropic gelation, showing entrapment efficiencies of over 90 %. Characterization techniques, including SEM, ATR-FTIR, FT-Raman, XRD, and 13C NMR, confirmed the efficient incorporation of aceclofenac and the preservation of its structure within the polymer matrix. In vitro dissolution studies demonstrated prolonged release profiles compared to the commercial formulation, with release times of around 180 min, i.e. approximately six times longer than conventional aceclofenac tablets. All developed formulations were gastroresistant, preventing premature drug release in simulated gastric medium. Mathematical modeling indicated that, depending on the formulation, drug release was governed by Fickian diffusion, Case II transport, or a combination of diffusion, matrix erosion and swelling.

Rare Earth Metals (REMs) are vital for advanced technologies, yet they face increasing supply risks, emphasising the need for efficient recovery from secondary resources such as NdFeB magnet waste. The present work details the development and characterisation of magnetically responsive vermiculite-based nanocomposites, with and without alginate immobilisation, aimed at the selective recovery of neodymium (Nd(III)) and dysprosium (Dy(III)) ions from synthetic solutions and real NdFeB magnet leachate. The composites were synthesised by incorporating Fe3O4 nanoparticles into vermiculite, and, in some cases, the resulting material was encapsulated in alginate beads. X-ray diffraction was utilised to confirm the formation of magnetite, while the magnetic responsiveness of all sorbents was sufficient for straightforward separation. The presence of additional functional groups, including hydroxyl, carboxyl, and silicate, was shown to enhance sorption performance. Although alginate immobilization significantly reduced sorption kinetics, it led to higher sorption capacities and enhanced structural stability. Non-immobilised materials exhibited greater selectivity for Nd(III) over Dy(III), a critical challenge in the separation of REMs. Regeneration studies confirmed the efficient metals desorption when complexing agents were utilised. The high sorption performance of these low-cost and eco-friendly nanocomposites in real leachate systems demonstrates their applicability for sustainable REM recovery from e-waste streams.

This study investigates continuous fixed-bed adsorption and catalytic ozonation for the removal of diclofenac sodium from aqueous media using green-synthesized multi-walled carbon nanotubes (green-MWCNTs) as multifunctional adsorbent-catalyst materials. The environmentally friendly synthesized MWCNTs provide active adsorption sites through pi-pi interactions, structural defects, and oxygen-containing functional groups, enabling adsorption and catalytic activity. Fixed-bed columns composed of green-MWCNTs combined with glass microspheres and colloidal amorphous silica were applied to improve nanotube dispersion, hydraulic stability, and accessibility of active sites during continuous operation. Material characterization confirmed preservation of nanotube structure and successful incorporation into the surface of microspheres. Breakthrough curves were well described by the Dual Site Diffusion model, indicating the presence of heterogeneous adsorption sites. Beyond adsorption, green-MWCNTs promoted ozone decomposition and formation of reactive oxidative species, enhancing diclofenac degradation during catalytic ozonation. Under optimized conditions (O3 concentration = 30 mu g mL-1, reaction time = 30 min, catalyst dosage = 2 g L-1), a maximum degradation efficiency of 76 % was achieved for an initial concentration of 0.2 mmol L-1. These results demonstrate the effectiveness of greenMWCNTs as scalable multifunctional material for both adsorption and advanced oxidation processes for water treatment applications.

We report the fabrication of CsPbBr3 perovskite quantum dot (PQD) solar cells using an environmentally friendly synthesis approach. CsPbBr3 PQDs were synthesized via ultrasonication using peanut oil as a green solvent, offering a sustainable alternative to traditional toxic solvents. For comparison, solar cells were also fabricated using PQDs synthesized in standard mineral oil. Devices based on peanut oil-derived PQDs exhibited higher overall power conversion efficiency (PCE), reaching up to 3.71%, compared to 2.23 % from mineral oil. To assess and optimize the quality of the active layer, different numbers of purification cycles were carried out as part of the post-synthesis processing by using methyl acetate and ethyl acetate. Additionally, the influence of the active layer thickness on device performance was systematically investigated. Stability measurements under continuous illumination revealed that the solar cells maintained a consistent performance level for over 18 h, highlighting the potential of this green synthesis approach. These findings demonstrate a promising and scalable route for the development of high-performance and eco-friendly PQD-based solar cells.

Conventional Raman spectroscopy is a powerful analytical technique but suffers from an inherently low sensitivity. This limitation can be overcome through surface-enhanced Raman scattering (SERS), a phenomenon traditionally achieved by using plasmonic substrates such as gold and silver nanostructures. Nonplasmonic materials, including nanostructures based on binary inorganic semiconductors, have emerged as promising alternatives because of their low cost, chemical stability, and tunability for specific applications. However, semiconductor substrates typically provide a lower Raman enhancement than plasmonic substrates, motivating the development of new substrate designs. In this work, we investigate the SERS activity of zinc oxide (ZnO), graphene oxide (GO), and a ZnO-GO hybrid material using 4-mercaptopyridine (4-MPy) as a molecular probe, combining experimental Raman measurements with computational modeling. Our results demonstrate that ZnO amplifies the Raman signal of 4-MPy, whereas GO does not contribute significantly to the enhancement mechanism. Computational analysis reveals that the observed Raman signal originates from a charge-transfer (CT) process, preferentially mediated by N-Zn and S-Zn bond formation. These findings confirm ZnO as a promising nonplasmonic SERS substrate and provide mechanistic insight into charge-transfer-induced enhancement observed in Raman experiments.

We report here research on magneto-plasmonic bionanocomposites (Fe₃O₄@SiO₂/SiκCRG/Ag) designed for the detection of water contaminants using surface enhanced Raman scattering (SERS) methods. These new substrates comprise a ferrimagnetic core (Fe₃O₄) coated with hybrid shells composed of amorphous silica and κ-carrageenan, an anionic polysaccharide. Silver nanoparticles (Ag NPs) were generated in situ via the reduction of aqueous Ag(I) in the presence of the magnetic bionanocomposites (Fe₃O₄@SiO₂/SiκCRG), resulting in SERS-active substrates with magnetic separation capabilities. The SERS performance of these substrates was evaluated for the detection of two organic dyes, methylene blue (MB) and malachite green (MG), as well as the antibiotic ciprofloxacin (CIP). We mapped the spatial distribution of both the model contaminants and Ag NPs on the magneto-plasmonic bionanocomposites using combined SERS analysis and Raman imaging studies. This approach enabled the detection of MB, MG, and CIP in spiked aqueous solutions, down to concentrations of 1 × 10-9 M for MB and MG, and 3 × 10-7 M for CIP. Furthermore, the suitability of these substrates for on-site analysis was demonstrated using a portable Raman device to detect single- and multi-component dye mixtures. We also explored their practical applicability in a more complex matrix by detecting CIP (3 × 10-5 M) in spiked water sample from the Aveiro lagoon. Noteworthy, we associate the improved performance of these substrates to the role of κ-carrageenan, which facilitates the assembly of Ag NPs, creating localized regions of high electromagnetic field intensity, preserving the SERS activity even after eighteen months of storage. The impact of temperature on the SERS signal was evaluated, revealing that the bionanocomposites maintain their activity after experiencing a temperature cycle. These findings indicate that these new SERS substrates are promising for practical sensing applications, particularly for on-site detection of water contaminants in remote regions.

Conventional photocatalysts suffer from inefficient charge separation and rapid recombination rate of the electron-hole pairs. The motivation of the present study is, hence, to develop a composite of CuO nanoparticles and O-doped-g-C3N4 (CN) to address the mentioned issues for the efficient removal of naphthalene (NAP), one of the most abundant polycyclic aromatic hydrocarbons (PAHs) in aquatic media. The nanoparticles were characterised by XRD, STEM, EDS, gas adsorption (BET isotherm), XPS, FTIR and band gap analysis. Mott-Schottky studies were performed to understand the formation of the heterojunction in the O-doped-g-C3N4-CuO (OGC) photocatalyst. The prepared n-p-type heterostructure nanocomposite with a tuned band gap energy (1.55 eV, compared to 2.49 eV for CN and 1.79 for CuO) offered efficient removal of NAP by promoting the generation and separation of electron-hole pairs. The optimisation indicated the best performance (87.1 % of 20 mg of NAP) of the system using OGC (0.25 g/L) at pH 6 under visible light irradiation in 60 min. The removal rate of NAP was studied by pseudo-first-order reaction rate kinetics in addition to mechanistic studies on the NAP degradation pathways using quenching tests, electron paramagnetic resonance (EPR) measurements, and gas chromatography-mass spectrometry (GC-MS). According to the results achieved, OGC is an efficient heterojunction for the degradation of NAP under visible light irradiation by producing both center dot O2- and center dot OH radicals. Such an efficient process can significantly aid in enhancing the quality of the polluted waters and protection of the environment.

The widespread use of gadolinium (Gd) in medical and industrial applications, especially as a contrast agent in magnetic resonance imaging (MRI), has led to its increasing presence in surface waters, disrupting natural geochemical cycles and posing risks to aquatic ecosystems. Addressing this challenge, recent studies have explored the potential of magnetic materials, such as spinel ferrite nanoparticles, in the removal of Gd from contaminated water sources. The present study specifically focused on the use of MnFe2O4 nanoparticles to remove Gd from contaminated solutions, employing response surface methodology (RSM) to optimize sorption conditions. Key variables evaluated included salinity (0–30 g/L), initial Gd concentration (1–5 μmol/L), and sorbent dose (20–180 mg/L), at a fixed pH of 6. The results revealed that salinity had a minimal impact on Gd sorption, likely due to the high sorbent mass used. Optimal conditions were identified as a sorbent dose of 165 mg/L, an initial Gd concentration of 1.3 μmol/L, and a salinity level of 13.4 g/L, at pH 6. The process was efficient and rapid, achieving over 90% Gd removal within 1 h in both freshwater and saline conditions, and over 75% removal in mineral water within 3 h. The high efficiency and celerity of this method suggest that MnFe2O4 nanoparticles are a promising solution for treating Gd-contaminated hospital effluents. Future research should focus on validating these results in real-world effluent matrices and addressing the environmental and economic aspects of large-scale implementation, thereby contributing to sustainable water remediation strategies.

Growing concerns among consumers and regulatory authorities regarding food safety have highlighted the need for effective detection and removal of hazardous substances. Rhodamine B (RhB), an illegal food dye with known genotoxic and carcinogenic properties, poses a significant threat to food safety and human health. In this study, we report for the first time the fabrication of multifunctional hybrid films composed of graphene oxide (GO) and molybdenum disulfide (MoS2) nanosheets for the dual purpose of RhB removal and surface-enhanced Raman scattering (SERS) detection. Hybrid films were engineered by varying the relative concentrations and compositions of the GO and MoS2. Structural analysis revealed that the increased MoS2 content in the hybrid films resulted in the formation of two distinct regions, a dense MoS2-rich bottom layer and a GO-enriched upper layer. Adsorption studies showed that the RhB removal efficiency increased with MoS2 content, achieving up to 99.9 % removal with films composed entirely of MoS2 (100 wt%). SERS analysis revealed a relationship between the MoS2 and GO content in the hybrid films and the Raman signal intensity of RhB. These outcomes can be attributed to the differences in the molecular interactions between RhB and the individual film components of the sensors. To balance the high adsorption efficiency with sensitive detection, hybrid films containing 75 and 100 wt% MoS2 (GO/MoS2_25/75, GO/MoS2_0/100, respectively) were selected for further validation. The proofof-concept was demonstrated using RhB-spiked sweet pepper powder, where the GO/MoS2_0/100 film achieved a detection limit of 0.01 wt% (100 ppm), and the GO/MoS2_25/75 film detected as low as 0.1 wt% (1000 ppm). In addition, RhB was detected in complex water samples, namely wastewater, mineral water, tap water, and Aveiro Estuary water, using the GO/MoS2_0/100 film, with a detection limit of 100 nM for the latter. Overall, this study introduces a new class of multifunctional 2D-material-based hybrid films that merge adsorption and SERS sensing capabilities within a single architecture, offering a technologically meaningful and simple approach for ultrasensitive, on-site monitoring and removal of illicit food dyes and related contaminants.

This study explores the use of manganese ferrite nanoparticles (MnFe2O4) for the removal and recovery of neodymium (Nd) from aqueous solutions, focusing on their potential application in wastewater treatment and environmental remediation. Neodymium, a critical element for the high-technology and energy industries, is increasingly present in aquatic environments due to its widespread use in devices such as computers, electric vehicles, and wind turbines. Through a series of kinetic, equilibrium, and desorption tests, the study optimized key operational parameters using Response Surface Methodology. Equilibrium analyses revealed that the Nd removal at equilibrium (qe) reached 8 mg/g, while the maximum sorption capacity (qm) was determined to be 9.2 mg/g. The results demonstrated a high removal efficiency (up to 90 %) under optimal conditions, which included a nanoparticle dose of 1000 mg/L, an initial neodymium concentration of 20 mu mol/L, pH 6, and no salinity. The material showed great potential for neodymium recovery from synthetic magnet solutions, with removal rates exceeding 70 %. Desorption tests confirmed complete recyclability of the sorbent. These findings highlight manganese ferrite nanoparticles as a promising and sustainable approach for neodymium recovery.

The demand for effective water treatment strategies has contributed for extensive research in materials chemistry, with great focus on advancing adsorbent technologies. This investigation centers on synthesizing and modifying carbonaceous materials, specifically biochar and its polyaniline composite (biochar@polyaniline: BC@PANI), to evaluate their effectiveness in eliminating hexavalent chromium Cr(VI) from aqueous solutions. The biochar composite was prepared using a straightforward in-situ chemical polymerization approach. The properties of biochar were modified by blending it with polyaniline at 25

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A crescente presença de contaminantes emergentes em corpos d’água tem impulsionado o desenvolvimento de materiais fotocatalíticos avançados capazes de promover a degradação eficiente desses poluentes. Neste contexto, a incorporação de semicondutores nanoestruturados em matrizes cerâmicas impressas em 3D apresenta-se como uma estratégia promissora para superar desafios clássicos da fotocatálise heterogênea, como a difícil recuperação do catalisador e a perda de eficiência em ciclos sucessivos. Assim, o presente estudo objetiva desenvolver, caracterizar e avaliar membranas cerâmicas impressas em 3D contendo ZnO e Nb₂O₅ nanocristalinos imobilizados, visando aplicações em processos de descontaminação de água. Para isso, foram sintetizadas partículas de ZnO e Nb₂O₅, incorporadas à matriz de metacaulim por meio de rotas empregando extrusão e posterior impressão 3D. As membranas foram caracterizadas por DRX, FTIR, MEV, EDX, Raman e UV-Vis, permitindo avaliar a formação de fases, morfologia, distribuição dos óxidos e propriedades ópticas. Os resultados indicam que a impressão 3D possibilita a obtenção de estruturas porosas, mecanicamente estáveis e com distribuição homogênea dos semicondutores, favorecendo a interação luz–catalisador e o fluxo de solução. Os testes iniciais de fotodegradação mostram atividade significativa frente ao antibiótico ciprofloxacino, evidenciando o potencial das membranas para uso em sistemas contínuos de tratamento de água. Conclui-se que a abordagem proposta integra de forma eficiente impressão 3D e fotocatálise, abrindo caminho para o desenvolvimento de dispositivos modulares e reutilizáveis para o tratamento avançado de efluentes.

This study describes the green synthesis of silver and gold colloids via the reduction of Ag(I) and Au(III) in the presence of distinct aqueous plant extracts, as well as the influence of various reaction parameters, such as reaction time, pH, and extract concentration, on the morphology, size, and stability of the nanoparticles. The method employed led to the formation of stable colloids containing polydisperse silver and gold nanoparticles, which were applied to the SERS detection of benzylpenicillin, a natural beta-lactam antibiotic also known as penicillin G (PG). Our results show that all Ag/Au colloids synthesised with Thymelaea plant extract exhibit effective SERS activity for PG detection at a concentration of 10-3 M, without significant interference from chemical adsorbates originating from the extracts. The assessment of antioxidant activity using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay revealed that AgNPs (IC50 = 12 mu g/mL) and AuNPs (IC50 = 20 mu g/mL) exhibit superior activity compared to the crude aqueous extract (IC50 = 30 mu g/mL). Transmission electron microscopy (TEM) analysis showed size variations of the nanoparticles depending on the concentration: for AgNPs, spherical particles with diameters of 15.0 nm (2 mg/mL), 20.4 nm (3 mg/mL), 23.5 nm (4 mg/mL), and 26.6 nm (5 mg/mL), and for AuNPs, spherical particles with average diameters of 17.2 nm (5 mg/mL), 27.3 nm (4 mg/mL), 32.7 nm (3 mg/mL), and 76.5 nm (2 mg/mL). Zeta potential measurements confirmed their stability, with all nanoparticles exhibiting negative surface charges. Moreover, pH variations had a minimal impact on their morphology.

Developing cost-effective and sensitive Surface-Enhanced Raman Spectroscopy (SERS) paper platforms represents a significant step forward for detecting specific water contaminants at ultra-low concentrations in remote regions of the globe. However, the hydrophilic, irregular, and porous nature of common paper often results in poor reproducibility and lack of uniformity of paper sensors. In this study, we developed efficient SERS substrates by combining office paper, polylactic acid nanoparticles (PLA NPs), and silver nanoparticles (AgNPs) using a two-step drop-casting method. In these substrates, the PLA NPs create a nano-rough film that reduces porosity and hydrophilicity of paper, while the AgNPs provide SERS activity. The film's packaging ability was optimized by adjusting the drying temperature of the PLA colloid, which significantly influenced the paper's wettability. Additionally, the drying temperature was found to substantially affect the loading of AgNPs on the substrate surface. Initial tests with rhodamine 6G as a model analyte showed that the optimal SERS response was achieved at a drying temperature of 100 degrees C, with a sixfold concentration of the Ag colloid. The effectiveness of these paper- based sensors was further demonstrated by detecting pesticides and antibiotics in mineral water, specifically paraquat and ciprofloxacin, with detection limits of 1 mu M and 200 mu M, respectively.

Liquid-phase exfoliation (LPE) is a widely used top-down approach for producing two-dimensional (2D) materials on a large scale, including transition metal dichalcogenides (TMDs). Conventional LPE procedures face significant challenges, namely the use of fossil-derived organic chemicals, such as solvents and stabilizing agents. However, the use of colloidal nanoparticles or inorganic nanostructures as stabilizing agents to exfoliate TMDs has been less explored despite offering the possibility to synthesize composites with unique properties. This research reports an innovative one-step approach for fabricating 2D MoS2/AuNPs composites with distinct morphologies using an ultrasound-assisted LPE. This method comprises the exfoliation of MoS2 commercial powders (bulk) using colloidal Au nanoparticles (AuNPs) and ultrasound waves, resulting in the synthesis of distinct plasmonic-based composites, depending on the sonication time. Several parameters were investigated to explore the production of MoS2/AuNPs composites, including the size and the coating of the AuNPs and the MoS2 bulk/AuNPs ratio. As a proof of concept, we have assessed the surface-enhanced Raman scattering (SERS) sensitivity of these nanocomposites for the biodetection of adenine. Selected samples of 2D MoS2/AuNPs composites sonicated for 30 min were shown to be more sensitive to detecting adenine than the composite components alone (2D MoS2 nanosheets and AuNPs).

This study explores the use of chitosan in the sustainable exfoliation of MoS2, optimizing conditions to create effective surface-enhanced Raman scattering (SERS) platforms for optical sensors. Two-dimensional (2D) materials such as molybdenum disulfide (MoS2) have attracted significant attention recently due to their unique electrical, optical, and mechanical properties. However, conventional methods for exfoliating MoS2, such as liquid-phase exfoliation (LPE) with toxic organic solvents, pose environmental and health risks, necessitating the development of more sustainable approaches. Here, we introduce chitosan as a green, multifunctional agent that plays a dual role: acting not only as an eco-friendly exfoliant for producing few-layer MoS2 nanosheets but also as a positively charged linker that drives the electrostatic assembly of Au nanoparticles (AuNPs). Several parameters, such as sonication time and biopolymer concentration, were systematically investigated to tailor the exfoliation efficiency and stability of the MoS2-chitosan biomaterials. This sustainable strategy yields MoS2-Ch1@AuNPs nanocomposites that function as highly active SERS substrates. Importantly, the synergistic interplay between MoS2, chitosan, and AuNPs leads to a substantial enhancement of detection sensitivity toward both crystal violet (limit of detection (LOD) = 10 nM) and glucose (clinically relevant 10 mM), outperforming the individual components (2D MoS2-Ch1 nanosheets or AuNPs alone). Beyond demonstrating high analytical performance, this work establishes a sustainable pathway for the design of biopolymer-mediated 2D nanocomposites bridging sustainability and advanced plasmonic sensing applications.