Materials Advances最新文献

Surface functionalization of graphitic carbon nitrides has been demonstrated to promote catalytic properties but has rarely been investigated with the 2D carbon nitrides poly(heptazine imide) (PHI) and poly(triazine imide) (PTI) despite their potential for a variety of applications. This may originate from the chemically inert and hence unreactive character of carbon nitrides in conjunction with the lack of possibilities to verify the success of a post-synthetic covalent functionalization. Herein, we address these problems and mainly investigate the possibility of covalently functionalizing PHI with any desired organic molecule. A strategy of using fluorine-containing functionalizations to enable access to ¹⁹F NMR studies is utilized, which ensures the complete removal of unreacted functional groups (FGs) and provides an easy and reliable quantification of the functionalization afterwards. Screening experiments illustrate the necessity to increase the accessibility to the surface. Furthermore, a high yield can be achieved by using acyl chlorides as functionalization agents. In addition, the proof of covalent functionalization is provided by means of 2D NMR on ¹⁵N-enriched PHI modified with a ¹³C-enriched FG. Our study thus presents a general route to the covalent functionalization of PHI and opens up new perspectives for rationally adding desired functionality to polymeric carbon nitrides in general.

The development of new photo-thermal catalysts for the transformation of CO₂ into fuels is of great interest, offering a clean and sustainable approach to reducing the carbon footprint. Herein, we present a novel hybrid material composed of a nanocrystalline metal halide perovskite (CsPbBr₃) supported on a two-dimensional titanium nitride (Ti₂N) MXene. Additionally, we demonstrate the importance of forming an external TiO₂ layer through partial oxidation of the MXene (POM–Ti₂N), which introduces catalytic centers and enhances photogenerated charge separation. Remarkable activity in the formation of CH₄ and CO was observed, with yields of 321 µmol g⁻¹ and 480 µmol g⁻¹, respectively. The selectivity of the reaction was found to be temperature dependent. The mechanism was thoroughly investigated using XPS and photoluminescence studies. XPS analysis revealed a significant chemical interaction between the CsPbBr₃ nanocrystals and the POM–Ti₂N MXene after the formation of the composite. Photoluminescence measurements revealed a considerably shorter emission lifetime for the hybrid catalyst (τ_ave = 1.73 ns) compared to that of the CsPbBr₃ nanoparticles (τ_ave = 25.32 ns), indicating strong interaction with the MXene. Furthermore, this research highlights the potential of combining metal halide perovskites with MXenes and the importance of controlling their interface for photo-thermal reactions.

Ammonium hydrogen phenylphosphonate (1) was investigated as a novel agent for the protection and consolidation of carbonate stone substrates. Compound 1 quantitatively reacted with calcium carbonate to give calcium phenylphosphonate dihydrate (2), which was characterized by spectroscopic and microanalytical means and whose structure was solved using 3D electron diffraction. Compound 1 was applied to artificially weathered Statuario white Carrara marble mock-ups through immersion, brushing, and spraying techniques, and its effect on structural, hygric, and mechanical properties was evaluated by means of a comprehensive set of techniques, including X-ray diffraction, ultrasonic velocity measurements, colorimetry, porosimetry, and contact angle measurements. While the application of well-known diammonium hydrogen phosphate (DAP) on carbonate stones results in the deposition of non-stoichiometric hydroxyapatite (HAP), the treatment with compound 1 results in the formation of a thin, homogeneous coating of stoichiometric compound 2 that enhances cohesion, reduces porosity, and improves mechanical resistance, restoring the marble properties to near-pristine conditions. The treatment induces only minimal chromatic changes, making it a promising solution for the conservation of stone cultural heritage.

Organofunctional silanes have garnered significant attention in materials science and nanotechnology due to their ease of use, rapid reactivity, and superior performance in adhesion, crosslinking, surface modification, moisture scavenging, and rheological enhancement. However, incorporating carboxyl functionality into alkoxysilanes remains challenging, largely due to their chemical instability arising from acid-catalyzed hydrolysis and intramolecular ring formation via O-acylation. In this work, we introduce an ultra-stable carboxyl silatrane (COOHSiT) engineered for controlled silanization to form thin, uniform, and functional organosilicon layers tailored for biosensor applications. The unique silatrane architecture characterized by a robust tricyclic cage and a stabilizing transannular N→Si dative bond imparts exceptional hydrolytic stability, preserving structural integrity throughout the organic synthesis and long-term storage, as confirmed by nuclear magnetic resonance (NMR) spectroscopy. Surface deposition of COOHSiT on silicon wafers was characterized using ellipsometry, contact angle goniometry, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy. The resulting films exhibited excellent uniformity and well-controlled thickness, attributable to the precise silanization and intermolecular hydrogen bonding between amide groups. Importantly, the COOHSiT coatings maintained accessible and reactive carboxyl groups, enabling efficient downstream functionalization via EDC/NHS chemistry for antigen/antibody conjugation. This platform was successfully employed for neurofilament light chain (NfL) detection using a fiber-optic nanogold-linked immunosorbent assay (FONLISA), achieving an impressively low limit of detection (LOD) of 0.56 fM. Altogether, COOHSiT emerges as a highly functional and stable organosilicon building block, opening new avenues for the development of advanced functional nanomaterials and biosensing technologies.

Correction for ‘A three-dimensional ZnO/TUD-1 nanocomposite-based multifunctional sensor for humidity detection and wastewater remediation’ by Aryan Boora et al., Mater. Adv., 2024, 5, 4467–4479, https://doi.org/10.1039/D4MA00191E.

Correction for ‘Efficient photo-oxidation of bisphenol a and tetracycline through sulfur-doped g-C₃N₄/CD heterojunctions’ by Ankoor Sura et al., Mater. Adv., 2024, 5, 5514–5526, https://doi.org/10.1039/D4MA00270A.

The transformation of seafood processing residues into advanced functional materials offers a dual solution to environmental pollution: mitigating waste streams while addressing water contamination. In this study, shrimp exoskeletons were valorized into a chitin–protein composite (SE-CP) through acid demineralization and thermal activation and evaluated as a biosorbent for the removal of anionic textile dyes Sellacid Red (SR) and Sellaset Blue (SB). The material was characterized using SEM, EDX, FTIR, XRD, BET, DLS, XPS, and PZC analyses, confirming a mesoporous structure (specific surface area = 51.4914 m² g⁻¹) enriched with amino and hydroxyl groups that favor electrostatic and hydrogen-bonding interactions. Batch adsorption studies showed maximum removal efficiencies of 99.2% for SR at pH = 3 and 98.7% for SB at pH = 4 both around 20 °C and an initial dye concentration of 100 mg L⁻¹. Kinetic data fitted the pseudo-second-order model (R² > 0.96), and equilibrium was best described by the Freundlich isotherm, with adsorption capacities of 158.43 mg g⁻¹ (SR) and 63.81 mg g⁻¹ (SB). SE-CP retained over 76% of its adsorption capacity after five regeneration cycles, indicating strong stability and reusability. This work demonstrates a low-cost and sustainable biosorbent derived from shrimp waste, with high efficiency, reusability, and green synthesis, positioning SE-CP as a promising candidate for industrial dye wastewater treatment within circular economy principles.

Semiconducting single-walled carbon nanotubes (SWCNT) functionalized with covalent defects are a promising class of optoelectronic materials with strong, tunable photoluminescence and demonstrated single photon emission (SPE). Here, we investigate sulfur-oxide containing compounds as a new class of optically active dopants on (6,5) SWCNT. Experimentally, it has been found that when the SWCNT is exposed to sodium dithionite, the resulting compound displays a red-shifted and bright photoluminescence peak that is characteristic of doping with covalent defects. We perform density functional theory calculations on the possible adsorbed compounds that may be the source of doping (S, SO, SO₂ and SO₃). We predict that the two smallest molecules strongly bind to the SWCNT with binding energies of ∼1.5–1.8 eV and 0.56 eV for S and SO, respectively, and introduce in-gap electronic states into the bandstructure of the tube consistent with the measured red-shift of (0.1–0.3) eV, consistent with measurements. In contrast, the larger compounds are found to be either unbound or weakly physisorbed with no appreciable impact on the electronic structure of the tube, indicating that they are unlikely to occur. Overall, our study suggests that sulfur-based compounds are promising new dopants for (6,5) SWCNT with tunable electronic properties.

Mechanically triggered polymeric nanocomposites offer a promising solution for sustainable chemical recycling and minimize environmental pollution. In this study, a flexible, biodegradable donor–acceptor nanocomposite artificial leaf was synthesized as a photocatalyst by incorporating magnesium tetra-phenyl-porphyrin (T) and aloe-vera-derived graphene (G) into polylactic acid (P) via the blown film method. This process yielded photocatalyst films with excellent mechanical properties, including ultra-high tensile strength, bending strength, impact strength, and surface hardness. The resulting film photocatalyst, PGT, was evaluated at three aloe-vera-derived graphene loadings (0.5%, 1%, and 1.5% G). Among these, the 1% PGT photocatalyst with an integrated donor–acceptor architecture incorporated into a nanocomposite artificial leaf as a film photocatalyst demonstrated the best performance, achieving significant levels of active 1,4-NADH regeneration (61.09 ± 0.59%) via solar light, which was efficiently used by the formate dehydrogenase enzyme to exclusively generate formic acid (HCOOH at approximately 146.62 ± 1.6 µmol) from CO₂. The PGT nanocomposite, with its extremely high tensile strength (25.322 MPa), tensile load (589.49 Newtons), strain (11.755%), bending strength (32.244 MPa), and impact energy (2.4615 J), can serve as a suitable material for tissue implants for various applications. The 1% PGT nanocomposite flexible artificial leaf as a film photocatalyst has a remarkable ability to fix CO₂ into HCOOH compared to the 0.5% and 1.5% PGT flexible film photocatalysts. Overall, the outcome demonstrates the potential and adaptability of these P-based nanocomposite artificial leaves (PGT), emphasizing their importance in photocatalysis, solar chemical synthesis, and scaffold-based tissue engineering.

Silver nanocomposites are used to develop photocatalysts for various environmental, energy, and biomedical applications. However, the stability, biocompatibility, and performance of these colloids for practical applications need further improvement. Herein, silver nanocomposites protected with polyphosphodiesters (PPDEs) were successfully synthesized. A conjugate was prepared by varying the ratio of phosphodiesters to silver acetate, which were then exposed to visible light to form the silver nanocomposites, known as PEP·Na_aAg_b-l (a and b correspond to the ratio of Na⁺ and Ag⁺ in the feed). Then, the stability, photocatalytic activity, and recyclability of the colloids were evaluated. The spectral changes observed before and after irradiation confirmed the formation of photogenerated nanocomposites. The morphology of PEP·Na_aAg_b-l was characterized by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and X-ray photoelectron spectroscopy (XPS). The silver nanocomposites efficiently degraded rhodamine B (RhB) under visible light, with the degradation efficiency of PEP·Na₅Ag₁-l reaching 89% (k = 5.12 × 10⁻² min⁻¹), indicating their photocatalytic performance. These nanocomposites achieved over 87% degradation of RhB even after six cycles, demonstrating their recyclability. The stability and recyclability of the colloids were reinforced by the polyphosphodiester. The role of specific reactive oxygen species (ROS) was explored by the conventional scavenger approach. The silver nanocomposites play a crucial role in the heterojunction, enhancing not only light harvesting but also increasing the capacity for electron acceptance and suppressing electron–hole recombination.