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The rapid treatment of organic dyes and tetracycline (TC) in industrial wastewater requires highly efficient semiconductor photocatalysts. In this study, the S-Scheme NH₂-MIL-125 (Ti-Zr)/ WO₃ composite material was successfully synthesized using a two-step hydrothermal method. A comprehensive analysis using X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), High Resolution Transmission Electron Microscopy (HRTEM), and Field Emission Scanning Electron Microscopy (FESEM) images revealed that WO₃ nanoparticles are intimately anchored on the NH₂-MIL-125 (Ti-Zr) nanodisks, forming a closely packed heterostructure. The bandgap values of WO₃ and NH₂-MIL-125 (Ti-Zr) were determined to be 2.58 eV and 2.67 eV, respectively. Through Response Surface Methodology (RSM), the optimal photocatalytic conditions for the degradation of simulated pollutants in real aqueous environments by the synthesized photocatalysts were explored. Under the full-spectrum irradiation of a 300 W xenon lamp, the TZW-2 composite photocatalyst exhibited a degradation rate of RhB, MB, and TC solutions as high as 95.7 %, 96.7 %, and 93 % within 90 min, respectively. The excellent photocatalytic performance of the composite photocatalyst originates from the establishment of S-scheme heterojunctions between NH₂-MIL-125 (Ti-Zr) and WO₃, which was confirmed by various characterization techniques such as XPS valence spectra, photoelectrochemistry, and free radical trapping experiments. The excellent stability of the prepared composite photocatalyst was further validated through three cycling test experiments. This work presents new ideas for constructing novel S-Scheme photocatalysts by combining bimetallic cluster MOFs and metal oxides for wastewater treatment.

For the first time, we proposed a novel approach to create enduring and robust fluorescent nanosheets by using MIBK as the backbone to form the 2D MIBK-Sn nanosheets (2D MIBK-Sn NS) for detecting ENR. These nanosheets were synthesized in situ using probe ultrasonication to facilitate the formation of MIBK-based 2D tin nanosheets. The LOD and LOQ for ENR in aqueous solutions was 4.90 and 16.1 nM, respectively. Linear calibration curves were obtained with correlation coefficient (R²) = 0.9920 in a linear range of 0–2 µM. Recovery results from real samples ranged from 90 to 106 % of the nominal values. Milk and urine samples were analyzed at concentrations ranging from 0.3 to 1.7 µM.

The rapid increase in electronic device usage has intensified electromagnetic interference (EMI), necessitating the development of shielding materials that are flexible, lightweight, cost-effective, and highly efficient. Two-dimensional (2D) materials have emerged as promising candidates for next-generation EMI shielding solutions due to their unique properties, such as low weight, mechanical flexibility, and affordability. This review explores the origins of electromagnetic responses and the shielding mechanisms, emphasizing photon-matter interactions. We also examine the instruments, methods, and standards for measuring shielding effectiveness, along with the underlying formulas for shielding efficiency (SE) calculation. Recent advancements in 2D materials for EMI shielding are analyzed, comparing their performance across various frequency ranges to other composites. In addition, the challenges ahead and their prospects are highlighted. We provide insight into forthcoming challenges in finding solutions for the next generation of shielding applications. The findings of this review provide valuable insights into the development of novel materials for EMI shielding and can guide future research in this field.

Understanding the design principles of efficient electrocatalysts using the structure–activity relationship is crucial for the advancement of energy-related applications, and specifically the hydrogen evolution reaction (HER). Non-precious electrocatalysts with low overpotentials are essential for driving the HER and achieving high energy efficiency. In this study, we synthesized and thoroughly investigated various heterostructures combining Mo and Sn sulfides, ranging from complete phase-separated hybrids to homogeneous mixtures: SnS@MoS₂ core–shell structures, SnS/MoS₂ with edge-rich Mo and (Sn_xMo_1-x)S with uniformly distributed Sn-Mo. Our findings reveal that the SnS@MoS₂ structure exhibited relatively high intrinsic activity characterized by a high electrochemical active surface area and rapid charge transfer kinetics, thereby enhancing the HER catalytic performance. The presence of fluffy MoS₂ layers provided an abundance of optimized sites for HER, potentially due to strain and defects such as S vacancies, known as active catalytic sites. The optimal structure facilitated efficient charge transfer from the core to the shell, improving conductivity and catalytic activity. Our research highlights the advantages of a core–shell hybrid structure, offering guiding principles for the development of an optimal SnS@MoS₂ catalyst.

There is a strong correlation between the concentration of creatinine in human urine and the overall health of the kidneys. Therefore, there has been a persistent need for a rapid, and cost-effective quantitative method to assay creatinine levels in urine. Herein, green fluorescent La³⁺ doped titanium carbide nanosheets (La³⁺-doped Ti₃C₂ NSs) are fabricated via HF etching method by using Ti₃AlC₂ as MAX phase material and La(NO₃)₃ as a doping agent. As synthesized fluorescent La³⁺-doped Ti₃C₂ NSs are stable, showing green fluorescence under UV light. The as-synthesized La³⁺-doped Ti₃C₂ NSs act as a fluorescent sensor for the sensitive recognition of creatinine biomarker. The La³⁺-doped Ti₃C₂ NSs-based fluorescence method showed a fluorescence quenching at emission wavelength 518 nm towards creatinine with a linear range of 0.25–7.5 μM and detection limit of 63.44 nM. The paper strip based on La³⁺-doped Ti₃C₂ NSs was developed for the visual identification of creatinine. Furthermore, La³⁺-doped Ti₃C₂ NSs were used as probes for imaging of Saccharomyces cerevisiae cells. Also, the as-fabricated La³⁺-doped Ti₃C₂ NSs propose a quick response giving a cost-effective analytical strategy for the selective assay of creatinine in biofluids (plasma and urine).

Inhibiting the rapid recombination of photogenerated carriers has been a serious challenge to improve photocatalytic efficiency. Constructing and boosting the built-in electric field in photocatalysts of 2D and 3D systems can effectively promote the separation and transfer of photogenerated charge carriers. Herein, we systematically summarize the construction principle, characterization methods about the direction and intensity of the built-in electric field, and several strategies to boost the built-in electric field including structure optimization, phase modulation, vacancy defects engineering, doping strategies, construction of charge transfer mediators. It is worth noting that the uneven charge distribution in the material (or differences in the position of the Fermi level) is a key issue in the construction and enhancement of built-in electric field. Finally, the application of the built-in electric field in photocatalytic water splitting, carbon dioxide reduction, nitrogen fixation and pollutant degradation are described. This review highlights a comprehensive understanding of the mechanism of built-in electric field in photocatalysis and offers some insights into the design and modification of photocatalysts for different applications.

Solar-driven conversion of CO₂ to value-added chemical fuels has been regarded as a promising strategy for solving the climate problem and energy crisis. To realize this goal, it is vital to design photocatalysts with abundant catalytic active sites and excellent charge separation efficiency. Here, perovskite nanocrystals (CsPbBr₃) were anchored on two-dimensional molybdenum nitride (MoN) using an in-situ growth method, forming a new and effective 0D/2D CsPbBr₃@MoN (CPB@MoN) nanoheterosturcture with close contact interface for CO₂ photoreduction. The introduction of MoN, acting as a charge transfer channel, could quickly trap the photoinduced charge from CsPbBr₃ and provide abundant catalytic sites for CO₂ photocatalytic reactions. For optimized CsPbBr₃@MoN composites, the CO yield was 13.86μmol/gh⁻¹ without any sacrificial reagent, which was a 4.5-fold enhancement of the pure CsPbBr₃. Further, in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) revealed the catalytic mechanism for the CO₂ photoreduction process. This work provides a new platform for constructing superior perovskite/MoN-based photocatalysts for photocatalytic CO₂ reduction.

Nanomaterials adorned on graphene comprise an essential component of a wide range of devices wherein graphene-based copper oxide nanocomposites have garnered significant attention in recent years. Copper oxides (CuO and Cu₂O) are semiconductors with distinctive optical, electrical, and magnetic properties. Their earth abundance, low cost, narrow bandgap, high absorption coefficient, and low toxicity of copper oxides are just a few key advantages. CuO is superior to Cu₂O in optical switching applications because of its narrower bandgap. Therefore, integrating graphene with copper oxides renders the ensuing nanocomposites much more valuable for various applications. Not surprisingly, a wide range of promising synthesis and processing techniques have been considered, focusing on multiple appliances such as sensors, energy storage, harvesting, and electrocatalysis. Herein, the most recent synthesis techniques and applications of doped, undoped, and hierarchical structures of CuO/Cu₂O-graphene-based nanocomposites are deliberated, including the potential future usages.

Compared to their three-dimensional (3D) counterparts, low-dimensional layered perovskite (2D) structures using bulky organic ammonium cations (PEA⁺) have significantly improved stability but generally worse performance. 3D perovskites with significant ion migration, one of the major concerns for structural instability, show better charge storage capacity. In contrast, strong van der Waals contacts and bulky spacer ligands in 2D perovskites inhibit the migration of halide ions. Mixed properties of 2D and 3D or quasi-2D layered perovskite demonstrate more efficient, tuneable optoelectronic properties and long-term stability. The performance and stability of the electrochemical supercapacitor may be significantly influenced by ion migration, as we have shown by fabricating porous electrodes from 3D-Cs₂AgBiBr₆ bulk perovskite, 2D/3D or quasi-2D PEA-Cs₂AgBiBr₆, and layered perovskite 2D PEA₄AgBiBr₈. The quasi-2D electrodes were found to have an energy density ∼1.75 times higher than the 3D perovskite electrodes and ∼4.5 times higher than that of pure 2D halide electrodes. Compared to 2D and 3D electrodes, quasi-2D has a maximum capacitance retention of around 93 % after 2000 operation cycles. Ex-situ X-ray diffraction was conducted to examine further structural changes in the quasi-2D, 2D, and 3D perovskite electrode materials. It was determined that the ordering arrangement of Ag⁺/Bi³⁺ cation improves the crystallinity of the structure, which enhances the device performance and stability of the quasi-2D electrode. Also, Ag³⁺ is essential for improving the strength of quasi-2D and 2D electrodes, as evidenced by X-ray photoelectron spectroscopy (XPS). A symmetric solid-state supercapacitor was fabricated and analyzed using a two-electrode method, demonstrating that the quasi-2D configuration has the highest energy density compared to the pure 2D and 3D perovskite electrode materials.