Nanoscale Advances最新文献

Since their discovery, two-dimensional Ti₃C₂T_x nanosheets have attracted significant interest for applications in energy storage, including batteries. Among the various strategies developed to enhance their properties, material combination and hybridization have emerged as particularly promising approaches. While much of the current research has centered on the use of Ti₃C₂T_x MXenes in anode or cathode electrode technologies, there is growing interest in exploring single- and multilayer MXenes for electrolyte applications. This expanding scope forms the basis and motivation for the present study.

In this study, we introduce a novel technique for creating a Molybdenum Disulphide f-Boron Nitride (MoS₂-(f-BN)) impregnated Cellulose Acetate (CA) composite with enhanced photodegradation properties for use in water treatment. The material comprises a heterostructure of functionalized boron nitride (f-BN) and molybdenum disulphide (MoS₂), synthesized within a cellulose acetate (CA) matrix. XRD, FT-IR, UV-vis, BET, TG-DTA, Raman, and PL investigations are among the extensive structural and optical characterization methods that verify the successful synthesis of the composite with a lowered bandgap of 3.3 eV, hence increasing its photocatalytic activity. Using a new MoS₂@(f-BN)@CA composite, this work examines the photocatalytic degradation of Crystal Violet (CV) dye when exposed to sunshine. The composite showed notable photocatalytic activity. Variables like irradiation time, pH, dye concentration, and catalyst dose were used to assess CV's degrading efficiency. The degradation reached over 86% after 120 minutes, according to the results, which increased with irradiation time. The composite performed best close to a pH of 6, which is neutral. The composite remained significantly active at all tested concentrations, despite the fact that greater dye concentrations initially caused more deterioration. CV elimination was also improved by raising the catalyst dosage. Adsorption investigations showed that the composite's adsorption behavior adhered to the Freundlich isotherm model, suggesting multilayer adsorption and a heterogeneous adsorption surface. The composite's heterogeneous composition and favorable adsorption were validated using the Freundlich isotherm characteristics. These results demonstrate the MoS₂@(f-BN)@CA composite's potential as an efficient and long-lasting photocatalyst for water purification applications, underscoring its viability for environmental remediation.

Rheumatoid Arthritis (RA) is a crippling autoimmune disease characterized by gradual cartilage loss, bone degeneration, and persistent joint inflammation. Widespread adverse effects and ineffective drug distribution hamper the traditional treatment modalities. Recent progress in RA treatment has been advanced by nanocarrier-based phototherapies, including photodynamic therapy (PDT) and photothermal therapy (PTT). These therapies work by inducing necrosis or apoptosis in inflammatory cells through the generation of reactive oxygen species via PDT or localized heat production by PTT. This also leads to a reduction in pro-inflammatory cytokines and modulates macrophage polarization (M1 to M2). This dual approach shows enhanced efficacy by targeting inflammatory cytokines while preserving healthy tissue function, providing site-specific delivery, and improving bioavailability. Preclinical investigations have demonstrated that functionalized nanocarriers for targeting macrophages and synovial fibroblasts show improved drug delivery and therapeutic outcomes. While clinical trials of PDT in refractory RA patients have shown promising results in targeting synovial hyperplasia and inflammatory markers with minimal side effects, the challenges of limited light penetration, hypoxic joint microenvironments, and poor target specificity reduce the efficacy of PDT. This review focuses on multifunctional nanoplatforms that integrate PDT and PTT therapies with nanocarriers, advanced light delivery systems, and phototherapy devices to optimise RA management. These innovations aim to enhance therapeutic precision, reduce symptoms, and improve patient adherence. It also explores cutting-edge advancements in RA treatment strategies, addresses current limitations, and proposes future research directions to bridge the gap between preclinical success and clinical application.

Cyanide and phenol are considered the major toxic pollutants in coke-oven wastewater. Cyanide, at a pH less than 10, is converted to HCN gas (pK_a = 9.2). Hence, cyanide treatment requires strongly alkaline conditions, i.e., a pH of more than 10; however, at such a high pH, the viability of microbes is not feasible. Therefore, to overcome this incompatibility, a sequential nano-bio treatment system was developed, integrating a novel carboxymethyl cellulose-polyvinylpyrrolidone-stabilized nanoscale zero-valent iron doped with palladium (CMC-PVP-nZVI/Pd) nanocomposite, followed by bio-treatment using R. pyridinivorans strain PDB9T N-1. The first nanostage was operated at pH 12 to stabilize cyanide (CN⁻) and initiate its removal, while the subsequent biostage was operated at a pH of 7.4 to achieve the complete removal of phenol. To prevent the atmospheric oxidation of nZVI and to improve its reusability and electron mobility, it was doped with palladium and conjugated with CMC and PVP. The synthesised nanomaterials were characterized using XRD, FTIR spectroscopy, FESEM, EDX, and XPS analyses. Results revealed that about 99% of cyanide was removed with an initial dose of 100 mg L⁻¹ at 30 °C using the nanocomposite, followed by the complete biodegradation of the remaining phenol (300 mg L⁻¹). The cyanide removal efficiency of the nanocomposite was 1.8-fold higher than that of the bare nZVI. Overall, the cyanide removal process followed a pseudo-2nd-order kinetics model, revealing a chemisorption nature with a superior sorption capacity of 93.37 mg g⁻¹. The intraparticle diffusion model showed that exterior mass transfer primarily governed the cyanide removal. Additionally, the nanocomposite exhibited strong reusability, demonstrating the efficacy of the proposed sequential nano-bio system.

Nano-enzymes are increasingly used in forensic identification, biochemical testing, food regulation, environmental pollution monitoring and other fields. However, the construction of enzyme cascade catalytic systems based on nano-enzymes with multiple enzyme activities presents both opportunities and challenges. Ti₃AlC₂ is a common MXene with a graphene-like structure, which has the features of a large specific surface area, good electrical conductivity, excellent catalytic properties, and easy functionalization. Moreover, after being functionalized, Ti₃AlC₂ can exhibit excellent peroxidase-like activity. Therefore, in this work, a bimetallic Fe–Ni@Ti₃C₂T_x nano-enzyme with both peroxidase-like and oxidase-like activities was synthesized, and three synergistic catalytic mechanisms of Fe–Ni@Ti₃C₂T_x were verified. A colorimetric sensor was constructed based on Fe–Ni@Ti₃C₂T_x for the detection of H₂O₂ to test its feasibility for practical applications. The prepared colorimetric sensor had a wide linear range (50–6000 µM) and a low detection limit (14.606 µM). In addition, the selectivity, stability and reproducibility of the prepared colorimetric sensor were acceptable. This study laid a foundation for the simple preparation and practical application of a bimetallic nano-enzyme with various enzyme activities.

In tandem with conductive carbon nanomaterials, redox-active spinel oxides offer a promising strategy to improve the efficacy of electrochemical energy storage devices. Among them, CuCo₂O₄ (CCO) has attracted considerable attention; however, systematic evaluations of its controlled morphology and diffusion dynamics in varied electrolytes remain scarce. In this study, we engineered CCO nanorods, spherical particles, and their nanocomposites with carbon nanotubes (5, 10, and 15 wt%), named CCO-I, CCO-II, and CCO-III, to investigate diffusion behaviour using the galvanostatic intermittent titration technique across different electrolytic conditions, along with key performance parameters. Electron microscopy verified the successful formation of the desired morphologies, where nanorods provided large surface-active sites and spherical particles offered high volumetric energy density. Electrochemical measurements in 1 M KOH, coupled with theoretical investigation using Dunn's model and determination coefficients (R²), revealed a mixed capacitive-faradaic charge storage nature of the samples. Among all variants, CCO-II delivered the best performance, with a specific capacity of 1702.01 C g⁻¹ along with an energy density of 113.46 Wh kg⁻¹. It also retained 99.94% capacity after 4500 cycles at 0.4 A g⁻¹, while galvanostatic intermittent titration technique showed balanced diffusion coefficients of 3.9 × 10⁻¹¹ cm² s⁻¹ in 1 M KOH and 4.1 × 10⁻¹¹ cm² s⁻¹ in 3 M NaOH. Further, the optimized sample exhibited low internal resistance and high ionic conductivity. Overall, these results highlight the potential of the CCO-II as a promising candidate for high-performance energy storage electrodes.

The engineering of two-dimensional (2D) layered materials through metallic and non-metallic doping has proven to be an intriguing strategy for achieving efficient water oxidation and high catalytic activities. The current study reveals the fabrication of a novel bifunctional Ag/Bi-doped MoS₂ catalyst with a fixed concentration (2 wt%) of bismuth (Bi) and varying concentrations (1 and 3 wt%) of silver (Ag) as dopants in MoS₂ (host) using a facile hydrothermal strategy. The Bi-doped MoS₂ catalyst with 3 wt% Ag exhibited an excellent catalytic activity of 99.57% for the elimination of RhB dye from water and flexibility in a wide pH range, signifying its catalytic dye-degradation potential in diverse pH environments. Additionally, the bifunctional catalyst demonstrated an outstanding electrocatalytic OER performance, requiring an overpotential of only 192 mV to reach a current density of 10 mA cm⁻² and a small Tafel slope of 65.3 mV dec⁻¹.

Trimetallic nanoparticles (TMNPs) have emerged as a versatile class of nanomaterials whose multifunctional and synergistic properties surpass those of mono- and bimetallic systems. This review examines the recent advancements in TMNP synthesis, bridging conventional top-down techniques with state-of-the-art bottom-up strategies that provide precise control over atomic ordering while addressing concerns related to sustainability. This review provides a systematic discussion of the structural and synthetic innovations resulting in their rapid adoption in electrochemical applications, including fuel cells, oxygen and hydrogen electrocatalysis, supercapacitors, and electrochemical sensing. Particular emphasis on the influence of interfacial and compositional engineering in TMNPs, ameliorating superior catalytic activity and stability over conventional catalysts, has been comprehensively highlighted. Finally, key challenges, including scalability, long-term stability, biocompatibility, and miniaturization, have been outlined for future opportunities for designing sustainable, application-oriented TMNPs. By linking fundamental structure–property relationships with electrochemical performance, this review contributes a unified framework for fabricating next-generation TMNPs towards energy conversion, catalysis, and advanced sensing applications.

An asymmetric supercapacitor (ASC) was developed using camphorsulphonic acid (CSA)-doped polypyrrole (PPY) nanorods as the positive electrode and activated carbon as the negative electrode. The CSA doping and rod-like morphology enhanced the conductivity and electrochemical activity of PPY. Density functional theory (DFT) analysis revealed that CSA significantly lowers the HOMO–LUMO energy gaps of pyrrole oligomers, particularly with increasing chain length, indicating improved electronic properties favorable for charge storage. Electrochemical testing showed that the pristine CSA-doped PPY electrode exhibited a moderate specific capacitance of 180 F g⁻¹ at 2 mV s⁻¹, which decreased at higher scan rates. However, after silver nanoparticle deposition on the PPY surface, it displayed a highly reversible and rectangular-type cyclic voltammetry (CV) profile, indicating ideal capacitive behavior, with a specific capacity of 527.28 F g⁻¹ at a scan rate of 2 mV s⁻¹. This enhancement was attributed to the strong interaction between silver and the CSA-doped PPY nanorods, which synergistically improved the capacitive performance. The energy density value obtained from the Ragone plot was 12.57 Wh kg⁻¹. These findings demonstrated the potential of metal-doped conductive polymers for high-performance supercapacitor applications. For real-time evaluation, cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) tests were performed on the assembled asymmetric supercapacitor (ASC). The ASC employed an Ag-deposited, CSA-doped polypyrrole (PPY) positive electrode and a biowaste-derived activated porous carbon negative electrode. The device delivered a specific capacitance of 208.88 F g⁻¹ at 2 mA cm⁻², with corresponding gravimetric energy and power densities of 41.78 Wh kg⁻¹ and 886.89 W kg⁻¹, respectively.

Supercapacitors (SCs) are garnering significant attention owing to their remarkable power density. Transition-metal-based MOFs have abundant valence states, which contribute to their superior stability, high energy density, and high power density. In this study, monometallic Fe-BDC MOF and bimetallic NiFe-BDC MOFs were synthesized with different molar ratios and examined for their application in supercapacitors. SEM-coupled EDX, BET, and XRD analyses were performed to determine their morphologies and microstructures. The electrodes were evaluated through cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) measurements in a 1 M KOH aqueous electrolyte. The Ni₁₀Fe₁-BDC MOF electrode exhibited the highest capacitance (918.75 F g⁻¹) at 4 A g⁻¹ due to its fast ion transport and low electrical resistance, resulting from its spherical structure. The Ni₁₀Fe₁-BDC MOF//Ni₁₀Fe₁-BDC MOF symmetric supercapacitor accomplished a high energy density of 106.42 Wh kg⁻¹ at a power density of 3720 W kg⁻¹ and exhibited a high rate capability of 137.73% after 2000 cycles, indicating its potential in supercapacitor applications.