Improvement of capacitance activity for Cu‐doped Ni‐based metal–organic frameworks by adding potassium hexacyanoferrate into KOH electrolyte

Cu‐doped Ni‐based metal–organic frameworks (MOFs) nanomaterials fabricated through a one‐pot hydrothermal reaction were characterized, and their performance as supercapacitor electrode materials was further studied for the first time. The results indicated that the doping of foreign metals and the introduction of K₃[Fe(CN)₆] in the KOH electrolyte significantly improve the performance of the supercapacitor. The results indicated that the Ni_2.6Cu_0.4 MOFs material shows the highest specific capacitance (1282 F g^?1 at 1 A g^?1 in mixed 2 M KOH and 0.1 M K₃[Fe(CN)₆]) and optimal capacitance retention (85.7% after 2000 cycles). This work provides a feasible optimization strategy for the construction of MOFs‐based supercapacitor electrode materials with excellent performance, and also provides a reliable experimental and theoretical basis for practical industrial production.     

The Role of Polarization in Photocatalysis

Semiconductor photocatalysis as a desirable technology shows great potential in environmental remediation and renewable energy generation, but its efficiency is severely restricted by the rapid recombination of charge carriers in the bulk phase and on the surface of photocatalysts. Polarization has emerged as one of the most effective strategies for addressing the above‐mentioned issues, thus effectively promoting photocatalysis. This review summarizes the recent advances on improvements of photocatalytic activity by polarization‐promoted bulk and surface charge separation. Highlighted is the recent progress in charge separation advanced by different types of polarization, such as macroscopic polarization, piezoelectric polarization, ferroelectric polarization, and surface polarization, and the related mechanisms. Finally, the strategies and challenges for polarization enhancement to further enhance charge separation and photocatalysis are discussed.     

Design,Synthesis and Antifungal Activity of Benzofuran and Its Analogues

Benzofuran has antifungal activity as the inhibitor of N‐myristoyltransferase. Twenty‐nine novel benzofuran‐semicarbazide hybrids were designed and synthesized by principle of drug combinationatory. On this basis, the benzofuran ring was simplified to a resorcinol structure, and sixteen novel 1,3‐dialkoxybenzene‐semicarbazide hybrids were designed and synthesized. All structures of the target compounds were characterized by HRMS and NMR. The in vitro antifungal activity of target compounds was evaluated using the microdilution broth method against eight strains of pathogenic fungi with fluconazole as positive control. According to the results of the target compounds, structure‐activity relationship (SAR) is summarized. The inhibitory activity against the tested strains of simplified compounds ( K01 — K16 ) has different levels improvement compared with compounds Z01 — Z29 . K01 — K16 showed significant antifungal activities against A. fumigatus, C. kruseii, and sensitive C. albicans 5314. Notably, compounds Z20 , Z22 , K10 , K11 and K16 also displayed different activities against two fluconazole‐resistance strains that were isolated from AIDS patients. The minimal inhibitory concentration (MIC) values against fluconazole‐resistant strains were in the range of 2—8 μg/mL and 4—32μg/mL, respectively. Furthermore, molecular docking was performed to investigate the binding affinities and interaction modes between the target compound and N‐myristoyltransferase.     

Topotactic Synthesis of Phosphabenzene‐Functionalized Porous Organic Polymers: Efficient Ligands in CO2 Conversion

Progress toward the preparation of porous organic polymers (POPs) with task‐specific functionalities has been exceedingly slow—especially where polymers containing low‐oxidation phosphorus in the structure are concerned. A two‐step topotactic pathway for the preparation of phosphabenzene‐based POPs (Phos‐POPs) under metal‐free conditions is reported, without the use of unstable phosphorus‐based monomers. The synthetic route allows additional functionalities to be introduced into the porous polymer framework with ease. As an example, partially fluorinated Phos‐POPs (F‐Phos‐POPs) were obtained with a surface area of up to 591 m² g^?1. After coordination with Ru species, a Ru/F‐Phos‐POPs catalyst exhibited high catalytic efficiency in the formylation of amines (turnover frequency up to 204 h^?1) using a CO₂/H₂ mixture, in comparison with the non‐fluorinated analogue (43 h^?1) and a Au/TiO₂ heterogeneous catalysts reported previously (<44 h^?1). This work describes a practical method for synthesis of porous organic phosphorus‐based polymers with applications in transition‐metal‐based heterogeneous catalysis.     

An Oligothiophene–Fullerene Molecule with a Balanced Donor–Acceptor Backbone for High‐Performance Single‐Component Organic Solar Cells

A new balanced donor–acceptor molecule, namely, benzodithiophene (BDT)‐rhodanine‐[6,6]‐phenyl‐C₇₁ butyric acid methyl ester (Rh‐PC₇₁BM) comprising two covalently linked blocks, a p‐type oligothiophene‐containing BDT‐based moiety and an n‐type PC₇₁BM unit was designed and synthesized. The single‐component organic solar cell (SCOSC) fabricated from Rh‐PC₇₁BM molecules showed a power conversion efficiency (PCE) of 3.22 % with an open‐circuit voltage (V_oc) of 0.98 V. These results rank are among the highest values for SCOSCs based on a monomolecular material. In particular, the one‐molecule Rh‐PC₇₁BM device exhibits excellent thermal stability compared to reference Rh‐OH:PC₇₁BM device. The success of our monomolecular strategy can provide a new way to develop high‐performance SCOSCs.     

Pothole‐rich Ultrathin WO3 Nanosheets that Trigger N≡N Bond Activation of Nitrogen for Direct Nitrate Photosynthesis

Nitrate is a raw ingredient for the production of fertilizer, gunpowder, and explosives. Developing an alternative approach to activate the N≡N bond of naturally abundant nitrogen to form nitrate under ambient conditions will be of importance. Herein, pothole‐rich WO₃ was used to catalyse the activation of N≡N covalent triple bonds for the direct nitrate synthesis at room temperature. The pothole‐rich structure endues the WO₃ nanosheet more dangling bonds and more easily excited high momentum electrons, which overcome the two major bottlenecks in N≡N bond activation, that is, poor binding of N₂ to catalytic materials and the high energy involved in this reaction. The average rate of nitrate production is as high as 1.92 mg g^?1 h^?1 under ambient conditions, without any sacrificial agent or precious‐metal co‐catalysts. More generally, the concepts will initiate a new pathway for triggering inert catalytic reactions.     

Uranocenium: Synthesis,Structure, and Chemical Bonding

Abstraction of iodide from [(η⁵‐C₅ⁱPr₅)₂UI] ( 1 ) produced the cationic uranium(III) metallocene [(η⁵‐C₅ⁱPr₅)₂U]⁺ ( 2 ) as a salt of [B(C₆F₅)₄]^?. The structure of 2 consists of unsymmetrically bonded cyclopentadienyl ligands and a bending angle of 167.82° at uranium. Analysis of the bonding in 2 showed that the uranium 5f orbitals are strongly split and mixed with the ligand orbitals, thus leading to non‐negligible covalent contributions to the bonding. Investigation of the dynamic magnetic properties of 2 revealed that the 5f covalency leads to partially quenched anisotropy and fast magnetic relaxation in zero applied magnetic field. Application of a magnetic field leads to dominant relaxation by a Raman process.     

The polyurethane/polyacrylate soap-free emulsion formation: effects of hydrophilic polyurethane

The vinyl group terminated water-borne polyurethanes (WPU) with different DMPA content were prepared. Subsequently the core-shell polyurethane/polyacrylate (PUA) composite emulsions were synthesized by soap-free emulsion copolymerization. The WPU as sole surfactant was used in copolymerization, and the lowest surface tension could be achieved to 38.8?mN m^?1. Furthermore, the final conversion of acrylic monomer was reached to 98% in the case of WPU reactive seed. The FTIR-ATR indirectly confirmed the core-shell structure of PUA, simultaneously combined with DSC results found that the compatibility of WPU and PA was enhanced by growing grafting efficiency. The TEM results further indicated that the amount of DMPA in WPU had a great significant role in polymerization and final morphology structure. The PUA composite particles changed from scattered structure, core-shell structure to multi-core structure with increasing DMPA content. Correspondingly, the reinforcing and toughening effects were also found in PUA films with the increase content of DMPA by tensile testing.     

An improved method of simultaneous determination of lutein and zeaxanthin in food

Based on an official standard method of lutein analysis, an improved high performance liquid chromatography (HPLC) method for simultaneously detecting lutein and zeaxanthin was developed as focusing on the sample preparation protocol. The optimal pretreatment conditions included a saponification in a water bath for 15?min at a constant temperature of 50?°C, using a 10?mL 60% (w/v) potassium hydroxide solution, followed by extraction using 100?mL mixture of n-hexane, ethyl ether and cyclohexane (40: 40: 20, v/v/v). A mixture of dichloromethane, acetonitrile and methanol (20: 30: 50, v/v/v) was validated to elute lutein and zeaxanthin on a C₃₀ column (4.6?×?250?mm, 5?µm). The resolution between lutein and zeaxanthin is ≥2.5. A millet sample was used for methodological verification and the results showed that the linear relations for lutein and zeaxanthin were good in ranges of 0.23–9.37?μg/mL and 0.30–12.02?μg/mL, respectively. The relative standard deviations of lutein and zeaxanthin were 1.40% and 5.09%, respectively, and their spiked recoveries were between 86.60% and 98.75%. The lutein and zeaxanthin results from this modified HPLC method are superior to those from the Chinese official method and ultrasonic extraction method.     

Environmentally Stable Polymer Gels with Super Deformability and High Recoverability Enhanced by Sub‐5 nm Particles in the Nonvolatile Solvent

It remains challenging to satisfy the combined performances for hydrogels with excellent mechanical behavior, high deformability, and super recoverability under harsh environmental conditions. In this study, we first established a strong polymer network via the crosslinking of polymer chains on the surfaces of sub‐5‐nm calcium hydroxide nanospherulites in ethylene glycol solvent. The organic gel expressed excellent mechanical properties such as a recoverable compressive engineering stress of 249 MPa and an elongation stress of 402 KPa, which was attributed to the uniform nanosized crosslinking structure as characterized by SEM. Moreover, the nonvolatile solvent remained in the gel, meaning that the sample can resist a wide temperature range of ?56 to 100 °C without losing the elastic properties. This novel organic gel could provide promising routes to develop the ideal elastic carriers for wearable devices, smart skin sensors, and damping materials. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 713–721