Zr–O clusters and BDC-NH2 linkers in Zr-MOFs were individually designed as recognition sites and fluorescent reporters for phosphate sensing.

Interface engineering is one feasible and effective approach to minimize the interfacial nonradiative recombination stemming from interfacial defects, interfacial residual stress, and interfacial energy level mismatch. Herein, a novel and effective steric-hindrance-dependent buried interface defect passivation and stress release strategy is reported, which is implemented by adopting a series of adamantane derivative molecules functionalized with CO (i.e., 2-adamantanone (AD), 1-adamantane carboxylic acid (ADCA), and 1-adamantaneacetic acid (ADAA)) to modify SnO 2 /perovskite interface. All modifiers play a role in passivating interfacial defects, mitigating interfacial strain, and enhancing device performance. The steric hindrance of chemical interaction between CO in these molecules and perovskites as well as SnO 2 is determined by the distance between CO and bulky adamantane ring, which gradually decreases from AD, ADCA, and ADAA. The experimental and theoretical evidences together confirmed steric-hindrance-dependent defect passivation effect and interfacial chemical interaction strength. The interfacial chemical interaction strength, defect passivation effect, stress release effect and thus device performance are negatively correlated with steric hindrance. Consequently, the ADAA-modified device achieves a seductive efficiency up to 23.18%. The unencapsulated devices with ADAA maintain 81% of its initial efficiency after aging at 60 °C for 1000 h.

A new benzoxazole-modified [PhSiO 1.5 ] 8 (OPS) benzoxazine (OPS−Bz) was synthesized and used to prepare polyhedral oligomeric silsesquioxane (POSS)/ polybenzoxazine (PBz) nanocomposites. Fourier transform infrared spectroscopy (FTIR), 1 H NMR, 29 Si NMR, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to characterize the structure of OPS−Bz. The high resolution transmission electron microscopy images of POSS/PBz(30/70) nanocomposites showed a well separated nanostructure of POSS with a typical phase size of 3−10 nm. POSS was highly dispersed in the polymer matrix because of the benzoxazole groups around the OPS molecular, in which the rigid benzoxazole groups increased the distance among the POSS molecules and reduced the aggregation of POSS nanoparticles. The TGA study showed these nanocomposites possess good thermal stability. Moreover, the dielectric constants and dielectric loss of these POSS/PBz nanocomposites were low and changed slightly at room temperature in the frequency range of 10 Hz to 1 MHz.

Introduction of large pore in the primitive microporous metal–organic frameworks (MOFs) with tailorable particle size can endow them with desired properties for potential applications in the intracellular delivery of membrane‐impermeable proteins. However, no research is found to focus on this topic until now. Herein, a monocarboxylic acid (MA) and organic base comodulation strategy is developed to synthesize the hierarchically porous UiO‐66 nanoparticles. MA of dodecanoic acid is utilized to control the pore size while trimethylamine (TEA) plays a key role in modulating the nucleation of crystallization to regulate the particle size. In comparison with microporous UiO‐66, a model protein of cytochrome c (Cyt c) could be efficiently loaded into the mesoporous MOFs (mesoMOFs). The size‐dependent cellular uptake is also evaluated, and it is verified that mesoMOFs with particle size of 90 nm could be endocytosed into living cells with highest efficiency. These outstanding merits enable the current mesoMOFs not only to exhibit efficient encapsulation of Cyt c but also facilitate the protein delivery into the cytosol and subsequent endosomal escape. Given the exceptional chemical stability, hierarchically porous structure as well as tunable particle size, the elaborated mesoUiO‐66 nanoparticles might offer a promising platform for a variety of biomedical applications.

Perovskite solar cells suffer from poor reproducibility due to the degradation of perovskite precursor solution. Herein, we report an effective precursor stabilization strategy via incorporating 3-hydrazinobenzoic acid (3-HBA) containing carboxyl (À COOH) and hydrazine (À NHNH 2 ) functional groups as stabilizer. The oxidation of I À , deprotonation of organic cations and amine-cation reaction are the main causes of the degradation of mixed organic cation perovskite precursor solution. The À NHNH 2 can reduce I 2 defects back to I À and thus suppress the oxidation of I À , while the H + generated by À COOH can inhibit the deprotonation of organic cations and subsequent amine-cation reaction. The above degradation reactions are simultaneously inhibited by the synergy of functional groups. The inverted device achieves an efficiency of 23.5 % (certified efficiency of 23.3 %) with an excellent operational stability, retaining 94 % of the initial efficiency after maximum power point tracking for 601 hours.

The primary pollutant, radioactive iodine (I), has become a worldwide concern due to its serious ill effects of radiotoxicity on human health. Therefore, it is of great significance to develop novel adsorbents for effectively eliminating I from nuclear waste. Herein, we reported a Zr-based MOF adsorbent constructed by utilizing pyridine-containing pyridine-dicarboxylic acid (PYDC) as organic ligands (UiO-66-PYDC) as well as active sites for the efficient removal of I. UiO-66-PYDC MOFs were synthesized by a hydrothermal strategy and featured good chemical and thermal stabilities, endowing them with the ability to work in harsh environments. The abundant and inherent pyridine moieties in the developed adsorbent worked as active adsorption sites to capture I. The correlation between the most significant parameters such as the contact time, adsorbate concentration, and reusability was optimized, and the interaction mechanism between I and UiO-66-PYDC was investigated in detail. As for the current adsorbent, a pseudo-second order rate equation was used to explain the removal kinetics, and the Langmuir model exhibited a better fit to the adsorption isotherm than the Freundlich model. Thanks to the strong affinity of PYDC ligands to I and high porosity, the adsorption capacities of UiO-66-PYDC for I could reach as high as 1250 mg g, which was much higher than those of many other reported MOFs. Additionally, the UiO-66-PYDC MOFs exhibited excellent renewable adsorption properties, prefiguring their great promise as green adsorbents for I removal in nuclear waste management.

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In the present study, two novel fully biobased benzoxazines were synthesized using modified products of rosin, dehydroabietylamine, guaiacol, 4-methylumbelliferone, and paraformaldehyde. The chemical structures of DM (dehydroabietylamine, 4methylumbelliferone) and DG (dehydroabietylamine, guaiacol) were characterized by Fourier transform infrared spectroscopy (FTIR), 1 H nuclear magnetic resonance (NMR) and 13 C NMR spectra, dimensional nuclear magnetic and high-resolution mass spectrometry. The curing process of DM and DG was monitored by differential scanning calorimetry and in situ FTIR. The results demonstrated that the corresponding polymers PDM and PDG had high thermal stability. In addition, they had low dielectric constants below 3.30 at 25 °C and 1 kHz condition. Water contact angle measurements, OPC-time curves, and Tafel plots of PDG and PDM were also studied. The results showed that anticorrosion performances of PDG and PDM were stable during the immersion process and had strong abilities as shield corrosive media. Therefore, these two benzoxazine resins based on dehydrobietylamine may have potential applications in many fields.