Materials Advances最新文献

Herein we report on the fabrication of a metal–organic framework (MOF)-based sensor using an NOTT-300 (Al) MOF thin film, deposited as a sensing layer on an interdigitated capacitive electrode (IDE), and deploy it for the detection of nitrogen dioxide (NO₂) at room temperature. The fabricated MOF-based sensor was tested and it demonstrated a significant detection sensitivity for NO₂ with concentrations down to 250 ppb, with a lower detection limit around 4.0 ppb. The NOTT-300 (Al) MOF sensor also displayed an outstanding NO₂ sensing stability and a highly desirable detection selectivity towards NO₂vs. other common gases such CO₂ and H₂O as well.

Six novel bicyclic and tricyclic difluoroboron NBN and OBN heterocycles were designed here in the quest for novel luminogenic molecular architectures because of their strong application potential as active layers in optoelectronics and as responsive units in sensing. They were prepared and then characterized with spectral (UV-vis, NMR, and luminescence) and electrochemical methods, and assessed via theoretical and X-ray investigations. Most of the compounds are non-emissive in solution, but luminescent in the solid state (red or yellow-green luminescence), and they are AIE active, offering excellent contrast for sensing schemes. Keeping this in view, two compounds were successfully embedded in Pluronic-silica nanoparticles (PluS NPs), coupling the AIEgenic properties of these compounds with the exceptional colloidal stability and functional surface of this type of nanostructure.

The limited operational lifetime of organic solar cells remains an obstacle to their commercial development and is largely due to the poor intrinsic photostability of the conjugated molecules that constitute the photoactive layer. Here, we selected a series of state-of-the-art donor and acceptor materials including PBDB-T, Y5, PF5-Y5, and PYT to study their photostability under AM1.5 simulated sunlight in ambient conditions. Their properties are monitored over time, using various spectroscopy techniques, including UV-Vis absorption, Fourier-transform infrared (FTIR), and X-ray and ultraviolet photoelectron spectroscopy (XPS and UPS). We found that the absorption spectra of Y5 and PYT films remain almost intact even after 30 hours of light exposure in air, while the PF5-Y5 and PBDB-T films undergo rapid photobleaching. The absorption losses observed in blend films of PBDB-T with Y5 and with PF5-Y5 can be understood as composed of contributions from the separate blend components that are similar to the absorption losses in neat films. The new peaks emerging in the FTIR spectra of PBDB-T, PF5-Y5, and their blend films witness the formation of new carbonyl groups, while these are absent in the spectra of the Y5 and PYT films. The XPS C 1s spectra of the PF5-Y5 and PBDB-T films confirm this carbonyl formation and the S 2p spectra reveal that sulphone groups are formed after 30 hours of exposure of these films. These results confirm that films of Y5 and the copolymer PYT are significantly more resistant to photooxidation, compared to the copolymer PF5-Y5. The comparison of these results suggests that the benzo[1,2-b:4,5-b′]dithiophene moiety with alkylated thiophenes as side chains (BDT-T) accelerates the photodegradation of PBDB-T and PF5-Y5. The replacement of the BDT-T unit by thiophene contributes to the enhanced stability of PYT, demonstrating that the nature of the co-monomer has a significant effect on the intrinsic photostability of Y5-based copolymers. These new insights are expected to stimulate the design of stable donors and acceptor polymers for the development of long-lived OPV devices.

Plasticizers have been widely utilized to adjust the glass transition temperature (T_g) of glassy polymeric materials. To optimize performance while minimizing volume, plasticizers with a strong affinity for the target polymer are typically chosen. If we consider a combination of a glassy polymer and a plasticizer with a critical miscibility condition, where the miscible/immiscible states are altered by changing the temperature, phase separation induced by temperature variations will trigger the glass transition. In this study, we report on a polymeric material synthesized from a blend of a high T_g polymer and a plasticizer, exhibiting a phase separation-induced glass transition around the upper critical solution temperature (UCST). It is expected from a crossover point of the T_g curve and the demixing curve in a thermodynamic phase diagram, corresponding to the Berghmann point. Poly(isobornyl acrylate) (PIBXA) with an original T_g of ∼100 °C and triethyl phosphate (TEP) were employed as the glassy polymer and plasticizer, respectively. When the TEP fraction was relatively small (∼10 wt%), the sample showed no phase separation and a decrease in T_g compared to that of the pristine PIBXA, following the conventional trend of plasticizer addition. Conversely, at 20 wt% or higher fractions, the samples displayed UCST-type phase separation and an abnormal increase in T_g with increasing plasticizer content. Furthermore, this miscible/immiscible transition can be predicted through an analysis of the temperature-corrected Hansen solubility parameter (HSP). This report proposes a novel role for plasticizers in adjusting T_g and prediction of objective combinations that satisfy the critical miscible condition.

The induction of structural distortion in a controlled manner through tilt engineering has emerged as a potent method to finely tune the physical characteristics of Prussian blue analogues. Notably, this distortion can be chemically induced by filling their pores with cations that can interact with the cyanide ligands. With this objective in mind, we optimized the synthetic protocol to produce the stimuli-responsive Prussian blue analogue A_xMn[Fe(CN)₆] with A = K⁺, Rb⁺, and Cs⁺, to tune its stimuli-responsive behavior by exchanging the cation inside pores. Our crystallographic analyses reveal that the smaller the cation, the more pronounced the structural distortion, with a notable 20-degree Fe–CN tilting when filling the cavities with K⁺, 10 degrees with Rb⁺, and 2 degrees with Cs⁺. Moreover, this controlled distortion offers a means to switch on/off its stimuli-responsive behavior, while modifying its magnetic response. Thereby empowering the manipulation of the PBA's physical properties through cationic exchange

Hierarchical linker thermolysis has been used to enhance the porosity of monolithic UiO-66-based metal–organic frameworks (MOFs) containing 30 wt% 2-aminoterephthalic acid (BDC-NH₂) linker. In this multivariate (i.e. mixed-linker) MOF, the thermolabile BDC-NH₂ linker decomposed at ∼350 °C, inducing mesopore formation. The nitrogen sorption of these monolithic MOFs was probed, and an increase in gas uptake of more than 200 cm³ g⁻¹ was observed after activation by heating, together with an increase in pore volume and mean pore width, indicating the creation of mesopores. Water sorption studies were conducted on these monoliths to explore their performance in that context. Before heating, _monoUiO-66-NH₂-30%-B showed maximum water vapour uptake of 61.0 wt%, which exceeded that reported for either parent monolith, while the highly mesoporous monolith (_monoUiO-66-NH₂-30%-A) had a lower maximum water vapour uptake of 36.2 wt%. This work extends the idea of hierarchical linker thermolysis, which has been applied to powder MOFs, to monolithic MOFs for the first time and supports the theory that it can enhance pore sizes in these materials. It also demonstrates the importance of hydrophilic functional groups (in this case, NH₂) for improving water uptake in materials.

A novel synthesis was performed of asymmetrical carboxamide ligand N,N′-bis(2-pyridinecarboxamide)-2-aminobenzylamine (H₂bpabza) derived from 2-pyridinecarboxylic acid and 2-aminobenzylamine. The N,N′-bis(2-pyridinecarboxamide)-2-aminobenzylamine (H₂bpabza) ligand was confirmed by ultraviolet-Visible (UV-Vis), Fourier transform infrared (FT-IR), and Raman spectroscopy. The fabrication of N,N′-bis(2-pyridinecarboxamide)-2-aminobenzylamine (H₂bpabza) embedded in a multi-walled carbon nanotube (MWCNT)-modified graphite electrode (GE) for use as an electrochemical sensor of Pb²⁺ and Hg²⁺ was demonstrated. The performance of the H₂bpabza/MWCNT electrode and (Pb²⁺ and Hg²⁺–H₂bpabza)/MWCNT was investigated by scanning electron microscopy (SEM) and square wave anodic stripping voltammetry (SWASV). In comparison to the MWCNT electrode, the H₂bpabza/MWCNT electrode exhibited higher sensitivity and conductivity, as determined by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Stripping analysis and detailed experiments were conducted to establish the optimal parameters for deposition and stripping of metal ions, such as supporting electrolytes, pH, and accumulation time. The linear range was 2 to 140 μg L⁻¹, with a detection limit of 0.1 μg L⁻¹ for Pb²⁺ and 0.3 μg L⁻¹ for Hg²⁺ (S/N = 3). The H₂bpabza/MWCNT-modified GE showed excellent sensitivity, selectivity, stability, and reproducibility for the determination of Pb²⁺ and Hg²⁺. Ultimately, the H₂bpabza/MWCNT-modified GE was used to demonstrate the electrochemical sensing of Pb²⁺ and Hg²⁺ in deveined shrimp and eggshells.

Lipid phosphatidylserine (PS) plays a vital role in the growth and proliferation of cancer cells and has been identified as a potential target for cancer treatment. Recent studies have focused on using phosphatidylserine-targeting agents in the treatment of several classes of cancer, such as breast, lung, and prostate. The use of PS-targeting antibodies to target cancer cells while leaving healthy cells unharmed is selective. These antibodies are specifically targeted to phosphatidylserine molecules located on the exterior membrane of cancer cells, triggering a series of events that ultimately destroy the cancer cells. In addition, incorporating phosphatidylserine into the liposome membrane specifically targets cancer cells, thereby enabling more efficient drug delivery and improving cancer treatment outcomes. In general, PS has active ingredients that are currently undergoing clinical trials for potential use in treating various types of cancer. On the role of phosphatidylserine in biophysical and cancer biology, this review summarizes recent studies, as well as related prospective clinical and preclinical trials such as immunotherapy and biomarkers. A new indication of future PS implementation in cancer therapy appears to be a new era.

This paper provides a comprehensive overview of the current state of lithium in Chile, with a forward-looking assessment in the context of the ongoing national lithium strategy. The global and regional significance of lithium as a critical energy resource is examined. The evolution of Chile's lithium industry is analyzed, emphasizing two recent key policy initiatives: the 2015 National Lithium Commission report and the newly launched national lithium strategy. The salient features of these initiatives are outlined. Additionally, this paper reviews materials science research conducted in Chile since the 1960s, particularly focusing on the physical chemistry of lithium, batteries and brines. Finally, the paper argues that lithium, as a pivotal material in the shift from fossil fuels to renewable energy, holds strategic potential for advancing the country's sovereign technological development.

In this study, a nano drug delivery system for sustained release (PSI–HAP) with spherical or near-spherical particles and a negative zeta potential was established. PSI–HAP was prepared using polysuccinimide (PSI) as the coating material and hydroxyapatite (HAP) as the drug adsorption core. By simply mixing PSI and HAP in solution, uniformly size non-agglomerated nanoparticles could be generated rapidly via a facile preparation process. Herein, HAP was prepared using the micro-emulsion method (MEM), liquid phase reaction (LPR), precipitation method (PM), or hydrothermal method (HM). The effects of the HAP preparation process on PSI–HAP were investigated. The optimal formulations and preparation processes of PSI–HAP were determined using single-factor experiments and the Box–Behnken design (BBD) response surface method with different model drugs. Additionally, the drug-loading and release features of PSI–HAP preparations were measured, and the distribution of SCE–PSI–HAP (Schisandra chinensis extract, SCE) in vivo was determined. The in vitro drug release test showed that PSI–HAPs were pH-sensitive, showing complete drug release around pH 7. Meanwhile, in vivo experiment demonstrated that in animals, the retention time was significantly longer in the SCE–PSI–HAP preparation group than in the saline group, irrespective of whether the formulation was administered orally or injected. The findings showed that the proposed drug delivery system is easy to prepare and sterilize, making large-scale production feasible, which could be used clinically for multi-modal drug delivery.