RSC Advances最新文献

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are critical half-reactions in energy conversion devices such as metal-air batteries and reversible fuel cells, and their sluggish kinetics severely limit the overall device performance. Therefore, the development of efficient, stable, and low-cost non-precious metal bifunctional electrocatalysts is of great significance. In this study, a MOF-derived bifunctional electrocatalytic material (NiFe@CNT), featuring NiFe bimetallic alloys uniformly anchored within a carbon nanotube network, was successfully fabricated using a two-dimensional metalloporphyrin-based Fe-MOF precursor via metal site modulation by introducing Ni, combined with a high-temperature pyrolysis strategy. Structural characterization results indicate that NiFe@CNT possesses an intact three-dimensional CNT conductive network, a high degree of graphitization (I _D/I _G = 0.39), and uniformly dispersed NiFe alloy active phases. Electrochemical evaluations reveal that NiFe@CNT functions as a highly active bifunctional catalyst for both ORR and OER in alkaline environments. Regarding its ORR activity, the material exhibits a half-wave potential comparable to that of benchmark Pt/C, with reaction kinetics proceeding through an approximately four-electron transfer mechanism. In terms of OER performance, a current density of 10 mA cm^-2 is attained at a modest overpotential of merely 1.514 V. In alkaline electrolyte, the ORR proceeds predominantly through a four-electron pathway converting O₂ to H₂O (O₂ + 4H⁺ + 4e^- → 2H₂O), while the OER involves the reverse four-electron oxidation of hydroxide to produce molecular oxygen (2H₂O → O₂ + 4H⁺ + 4e^-). Furthermore, durability assessments confirm that NiFe@CNT surpasses commercial noble metal benchmarks in long-term operational stability. This work presents a viable approach for fabricating advanced noble-metal-free oxygen electrocatalysts through two-dimensional MOF-derived engineering.

In an effort to promote eco-friendly organic synthesis, a facile, sustainable, and highly efficient procedure for the synthesis of 2-amino-1,3-thiazole derivatives was developed. The protocol of this process incorporates the principles of green chemistry. Moreover, the NMR, FT-IR, and UV simulations of the compounds were conducted at the B3LYP/6-311++G** level for comparison with the observed counterparts. FMO analyses revealed that the PhTA compound exhibited the highest stability via back-donation; among the compounds, NapTA exhibited the lowest stability via back-donation. Furthermore, the -NH₂ group did not influence electrophilic attacks because the LUMO for all compounds did not separate from this group. Also, the lipophilicity, solubility, pharmacokinetics, and drug-likeness profiles of the compounds were evaluated. The BOILED-Egg model implied that the compounds PhTA, BFTA, and NapTA permeate through the BBB (blood-brain-barrier) passively, while the FTA and ThTA compounds have no potency in terms of BBB penetration. Also, all compounds met the requested physicochemical criteria according to the Lipinski, Veber, and Egan rules. Additionally, the molecules were analyzed using the molecular docking method to gain insights into their possible anticancer activity. Vascular endothelial growth factor receptor-2, human estrogen receptor, human cytochrome P450, and human extracellular signal-regulated kinase 2 were selected. All the obtained results are expected to provide important insights into the structure-reactivity relationship in early-stage drug design research.

Ganoderma boninense infection affects nearly half of Indonesia's palm oil plantations, which leads to severe economic losses. Conventional detection methods like PCR are limited by cost and complexity, while electrochemical detection offers a promising alternative by targeting plant-derived metabolites. This study focuses on developing a low-cost, custom fabricated screen-printed electrode (SPE) modified with MWCNTs and Au/Pt nanoparticles to enable practical, scalable early detection of G. boninense in oil palm plantations using various electrochemical techniques. The SPE was fabricated using conductive carbon ink on sticker paper and modified with MWCNT-Au/Pt nanocomposites to enhance performance. Pt nanoparticles (2.5, 5, and 10 mM) were synthesized hydrothermally, while Au (5 mM) was prepared via citrate reduction. The nanocomposites were formed by sonication and applied via drop-casting. Characterization was performed using UV-vis, FTIR, XPS, SEM, contact angle, four-point probe, CV, and EIS. Electrochemical detection of phytol, quinoline, and stigmasterol was conducted using DPV and chronoamperometry in phosphate buffer saline. The results indicate that surface modification enhances conductivity and hydrophilicity, improving the charge transfer process in electrochemical detection. The best combination for SPE modification was the 3 : 1 ratio and 5 mM Pt concentration. The best detection results using DPV were achieved for phytol, quinoline, and stigmasterol, with respective R ² and LOD of 0.98 and 2.85 mM, 0.95 and 2.36 µM, and 0.98 and 1.36 µM. Repeated testing on the SPE demonstrated good stability, despite being designed as a disposable test kit. Further, the SPEs demonstrate low detection limits and high sensitivity, highlighting their potential for early diagnosis and rapid screening of Ganoderma-infected oil palm trees as an accessible alternative for disease prevention.

The accumulation of conventional plastics has increased the need for sustainable alternatives, particularly those derived from renewable resources. Among these, polylactic acid (PLA)-based industrial materials have emerged as prominent candidates for replacing conventional plastics in various applications. PLA, a biodegradable and compostable polymer synthesized from renewable resources, such as cornstarch and sugarcane, offers several advantages, including environmental friendliness and lower greenhouse gas emissions. This review examines the current state of PLA-based bio-packaging materials, focusing on their features, production processes, and performance in comparison to traditional plastics. This review discusses advancements in PLA technology, including routes for enhancing its mechanical strength, thermal stability, and barrier properties, which are critical for its application in various packaging scenarios. Additionally, this review addresses the challenges associated with PLA, including its limited availability, higher cost compared to conventional plastics, and issues related to its end-of-life disposal and recycling.

We report the synthesis and comprehensive characterization of Er³⁺-doped NaCaGd(WO₄)₃ phosphors with dopant concentration (0-7%) via solid-state reaction methodology. Rietveld refinement of synchrotron X-ray diffraction data confirms a phase-pure tetragonal scheelite structure (I4₁/a) with successful lattice-tuned substitution of Gd³⁺ by Er³⁺ ions, with unit cell contraction indicating homogeneous incorporation. Morphological studies via scanning electron microscopy demonstrate uniform particle distribution with compact grain morphology. Luminescence analysis reveals vivid green emission (CIE: x = 0.337, y = 0.587) from ²H_11/2 and ⁴S_3/2 excited states, under 325 nm excitation. The material exhibits exceptional thermometric performance through non-contact fluorescence intensity ratio thermometry over 298-573 K, with Boltzmann-distributed thermal quenching behavior: relative sensitivity peaks at 1.55% K^-1 near ambient conditions, coupled with an absolute sensitivity of 1.81 × 10^-2 K^-1 and sub-kelvin thermal resolution (±0.15 K at 300 K), values competitive with state-of-the-art rare-earth thermophosphors. The combination of optical stability, tunable green emission from efficient host-sensitization, and sub-kelvin temperature discrimination positions NaCaGd(WO₄)₃:Er³⁺ as a bifunctional material for next-generation solid-state lighting, full-color display systems, and non-contact high-precision thermal sensing.

Water contamination by phenolic compounds remains a critical environmental challenge, requiring adsorbents that combine high efficiency, structural stability, and facile recovery. In this study, we report a novel heterostructured composite, SrSnFe₂O₄@δ-MnO₂/BC_KOH, synthesized from cotton-branch-derived biochar through sequential KOH activation, MnO₂ growth, and magnetic ferrite incorporation. Unlike conventional MnO₂/biochar systems, the incorporation of SrSnFe₂O₄ induced α-to-δ MnO₂ phase transformation, heterointerface strain, and defect formation, enhancing surface functionality and adsorption reactivity. Comprehensive characterization (SEM, XRD, BET, XPS, VSM) confirmed a highly porous carbon framework, abundant oxygen-containing groups, and strong magnetic properties (M _s = 54.87 emu g^-1), enabling efficient pollutant capture and rapid magnetic separation. The composite exhibited excellent adsorption of o-nitrophenol (o-NP), achieving 99.04% removal within 60 min and a maximum adsorption capacity of 525.51 mg g^-1. Adsorption followed the Freundlich isotherm and pseudo-second-order kinetics, and XPS analysis revealed synergistic interactions between surface functionalities and o-NP molecules. The material maintained good reusability (50.29% after five cycles) and demonstrated effective removal in real wastewater samples. This work presents a scalable strategy for constructing magnetically retrievable δ-MnO₂/biochar heterostructures with superior adsorption performance, highlighting their potential for practical wastewater remediation.

In this study, we employ density functional theory to systematically investigate the properties of novel Janus ZCrBSe₂ (Z = N, P, As) monolayers. These two-dimensional semiconductors are found to be dynamically and thermally stable and to possess narrow band gaps. Owing to their intrinsic structural asymmetry and the resulting breaking of out-of-plane inversion symmetry, spin-orbit coupling not only induces Zeeman-type spin splitting but also gives rise to pronounced Rashba-type spin splitting in all proposed Janus structures. Furthermore, we comprehensively analyze the role of different phonon scattering mechanisms in determining the carrier mobility. The results demonstrate that acoustic deformation potential scattering is the dominant limiting factor and plays a decisive role in setting the total carrier mobility over a wide range of conditions. Beyond intrinsic phonon scattering, carrier concentration is shown to have a significant impact on mobility behavior, particularly for ionized impurity scattering, whose associated mobility exhibits a strong dependence on carrier density. These findings highlight the intricate interplay between intrinsic lattice vibrations and extrinsic impurity effects in governing carrier transport in Janus two-dimensional materials.

To address the increasingly serious electromagnetic pollution problem in the era of 6G communication, electromagnetic wave-absorbing materials have gradually become a research focus in modern society. In this work, cassava starch was selected as the precursor, and FeCoNi precipitates were introduced. Starch-based aerogel/FeCoNi composite wave-absorbing materials (FeCoNi/SA) were obtained through sol-gel and freeze-drying processes. Afterward, starch-based carbon aerogel/FeCoNi composite wave-absorbing materials (FeCoNi/SCA) were produced via high-temperature carbonization in a vacuum muffle furnace. The microstructure, chemical features, and wave-absorbing performance of FeCoNi/SCA were examined, and the absorption mechanism was discussed. The results indicated that at a matching thickness of 3 mm, the minimum reflection loss (RL_min) reached -60.89 dB, and the effective absorption bandwidth (EAB) was 6.27 GHz (7.31-13.58 GHz). When the matching thickness increased to 3.5 mm, the EAB expanded to 7.91 GHz (5.61-13.52 GHz). This type of material combines a lightweight porous architecture and a magnetic-dielectric synergistic loss effect, providing a feasible strategy for the development of high-efficiency and environmentally friendly wave-absorbing materials.

Monitoring bacterial biosynthesis in real-world developments using electrochemical sensing has been a challenging task. Our research focused on fabricating and optimizing a sustainable and economical electrochemical sensor (GB-CG) to quantify glycine betaine (GB) amount in various bacterial cultures. The sensor's design was based on the ion-association complex between GB and phosphotungstic acid (PTA) anion as an ion exchange site, using polyvinyl chloride (PVC) as the main polymeric matrix and dioctyl phthalate (DOP) as a solvent mediator/plasticizer. It exhibited a rapid, linear, and stable linear Nernstian response (57.52 mV per decade) over a wide concentration range (1 × 10^-7 to 1 × 10^-1 M), with a detection limit of 1 × 10^-8 M. The performance of the proposed sensor was evaluated in terms of selectivity, response time, operational lifespan, and pH/temperature working range, together with the key validation parameters. In comparison to a reported HPLC method, the sensor was efficiently utilized to determine the GB amount in three different bacterial cultures. The selected bacterial species were Escherichia coli, Bacillus subtilis, and Corynebacterium glutamicum. The sensor was also evaluated by using a Trichromatic Sustainability Assessment (TSA) protocol to ensure its environmental compatibility, sustainability, and practicality. Also, the proposed sensor was statistically compared to recently reported GB sensors, proving its reliability and optimal performance.

Recent advances in modern medicine emphasize patient-centric and personalized therapeutic strategies, particularly for chronic and regenerative applications. Among emerging biomaterials, chitosan (CS) has gained considerable attention due to its biocompatibility, biodegradability, and antimicrobial properties, while its molecular weight strongly influences structural organization and interactions with active compounds. In this study, chitosan-based matrices-2% (w/v) low-molecular-weight CS, 4% (w/v) low-molecular-weight CS, and 2% (w/v) medium-molecular-weight CS-were developed and enriched with ibuprofen (IBU), a widely used non-steroidal anti-inflammatory drug, to improve topical delivery and reduce systemic side effects. The physicochemical properties of gelled thin films were investigated with emphasis on molecular arrangement, surface characteristics, and drug release behavior in phosphate-buffered saline. ATR-FTIR spectroscopy, contact angle measurements, and atomic force microscopy (AFM) were employed to evaluate structural and functional changes induced by IBU incorporation. Medium-molecular-weight CS exhibited lower water contact angles (≈69-73°) and higher surface free energy (≈41-44 mN m^-1) compared to low-molecular-weight CS, while IBU loading did not significantly alter wettability. AFM analysis revealed drug-induced surface roughness changes, with Ra increasing from 23.9 nm (2CS_M) to 29.4 nm after IBU loading and further to 35.5 nm following release. ATR-FTIR spectra confirmed preservation of characteristic chitosan amide I and II bands (∼1645 and ∼1556 cm^-1), with spectral changes in the 1450-1700 cm^-1 region indicating interactions between IBU and CS functional groups. Among the investigated systems, 2% (w/v) medium-molecular-weight chitosan demonstrated the most favorable sustained IBU release (∼50% after 48 h), highlighting its potential for dermal drug delivery and personalized therapeutic applications.