The authors provide at a look at the biological applications of supramolecular assemblies that have been designed for excitation energy transfer. The topics discussed include biosensors and ...bioimaging.
P2‐type layered oxides suffer from an ordered Na+/vacancy arrangement and P2→O2/OP4 phase transitions, leading them to exhibit multiple voltage plateaus upon Na+ extraction/insertion. The deficient ...sodium in the P2‐type cathode easily induces the bad structural stability at deep desodiation states and limited reversible capacity during Na+ de/insertion. These drawbacks cause poor rate capability and fast capacity decay in most P2‐type layered oxides. To address these challenges, a novel high sodium content (0.85) and plateau‐free P2‐type cathode‐Na0.85Li0.12Ni0.22Mn0.66O2 (P2‐NLNMO) was developed. The complete solid‐solution reaction over a wide voltage range ensures both fast Na+ mobility (10−11 to 10−10 cm2 s−1) and small volume variation (1.7 %). The high sodium content P2‐NLNMO exhibits a higher reversible capacity of 123.4 mA h g−1, superior rate capability of 79.3 mA h g−1 at 20 C, and 85.4 % capacity retention after 500 cycles at 5 C. The sufficient Na and complete solid‐solution reaction are critical to realizing high‐performance P2‐type cathodes for sodium‐ion batteries.
A high sodium content (0.85) and plateau‐free P2‐type cathode, Na0.85Li0.12Ni0.22Mn0.66O2, is developed for sodium‐ion batteries. The sodium content promises a large specific capacity of 123.4 mA h g−1 with an average working voltage as high as 3.5 V. The complete solid‐solution reaction over a wide voltage range ensures small volume variation (1.7 %) and fast Na+ kinetics (10−10 to 10−11 cm2 s−1), contributing to both excellent cycling stability and rate capability.
Porous materials capable of selectively capturing CO2 from flue‐gases or natural gas are of interest in terms of rising atmospheric CO2 levels and methane purification. Size‐exclusive sieving of CO2 ...over CH4 and N2 has rarely been achieved. Herein we show that a crystal engineering approach to tuning of pore‐size in a coordination network, Cu(quinoline‐5‐carboxyate)2n (Qc‐5‐Cu) ena+bles ultra‐high selectivity for CO2 over N2 (SCN≈40 000) and CH4 (SCM≈3300). Qc‐5‐Cu‐sql‐β, a narrow pore polymorph of the square lattice (sql) coordination network Qc‐5‐Cu‐sql‐α, adsorbs CO2 while excluding both CH4 and N2. Experimental measurements and molecular modeling validate and explain the performance. Qc‐5‐Cu‐sql‐β is stable to moisture and its separation performance is unaffected by humidity.
Sieves you right: Crystal engineering of supramolecular isomers of Cu(quinoline‐5‐carboxyate)2n metal–organic materials enables the right pore‐chemistry for ultra‐high CO2/N2 and CO2/CH4 selectivity even in the presence of water vapor.
Pure organic room temperature phosphorescence (RTP) has unique advantages and various potential applications. However, it is challengeable to achieve organic RTP under visible and near-infrared ...(NIR)-light excitation, especially in aqueous solution. Herein we assemble difluoroboron β-diketonate compounds to form organic nanoparticles (NPs) in water. The resulting NPs are able to show efficient RTP, effective uptake, and bright imaging of HeLa cells under both visible- and NIR-light excitation. More strikingly, spectroscopic study, single-crystal X-ray diffraction, and DFT calculation reveal that the efficient RTP in organic NPs is originated from dimers in their excited states. The multiple interactions and intermolecular charge transfer in the dimer structures are of significance in promoting the production of dimer triplet excited states and suppressing the nonradiative decays to boost the RTP under visible- and NIR-light irradiation in water.
A facile approach for the preparation of supramolecular polymer‐based fluorescent nanoparticles (FNPs) is reported. FNPs with homogeneous shape and size distribution are fabricated from ...low‐molecular‐weight molecules, and thus, different compositional constituents can be efficiently incorporated via copolymerization. The emission color of the FNPs covers a wide region from blue to near infrared and can be easily tuned using efficient excitation energy transfer. The photoswitchable fluorescent nanoparticles with high on–off fluorescence contrast are also simply prepared by copolymerization of monomers containing a fluorophore and a photochromic unit. Our FNPs are successfully applied in living cell imaging and as fluorescent inks.
A new set of fluorescent nanoparticles (FNPs) are fabricated from hydrogen‐bonded supramolecular polymers. Their preparation is straightforward, and nanoparticles with homogeneous shape and size are obtained. The emission color of the FNPs covers a wide region from blue to near infrared and is easily tunable by excitation energy transfer. These FNPs are successfully used in bioimaging and as fluorescent inks.
The first example of a ratiometric optical oxygen nanoprobe based on a hydrogen‐bonded supramolecular polymer has been reported. The supramolecular polymer based nanoprobe (SPNP) is prepared from the ...co‐assembly of a bis‐ureidopyrimidinone (bis‐UPy)‐containing phosphorescent indicator (Por(Pd)‐bisUPy), fluorescent reference dye (BF2‐bisUPy), and skeleton unit (DPA‐bisUPy) through quadruple hydrogen bonds by a mini‐emulsion method. The water‐dispersible SPNP is highly sensitive to oxygen (Q = 95%), with full reversibility, excellent storage stability and photostability, and good cell‐penetrating ability, and exhibits low cytotoxicity toward living cells. The preparation of the SPNP is straightforward and its function is easily tuned by changing the monomeric structure. This work is expected to lead to the design of other SPNPs for other important analytes in biological systems.
The first water‐dispersible supramolecular‐polymer‐based ratiometric oxygen nanoprobe (SPNP) is reported. The preparation of the SPNP is straightforward and its function is easily tuned by changing the monomeric structures. The SPNP is highly sensitive to oxygen, with full reversibility, excellent storage stability and photostability, and good cell‐penetrating ability, and exhibit low cytotoxicity toward living cells.
Sludge aggregation and biofilm formation are the most effective approaches to solve the washout of anammox microorganisms. In this study, the structure and composition of EPS (extracellular polymeric ...substances) were investigated to elucidate the factors for the anammox aggregation property. Anammox sludge taken from 18 lab-scale and pilot-scale reactors treating different types of wastewater was analyzed using EEM-PARAFAC (excitation–emission matrix and parallel factor analysis), FTIR (Fourier transform infrared spectroscopy) and real-time PCR combined with multivariate statistical analysis. The results showed that slime and TB-EPS (tightly bound EPS) were closely related with water quality and sludge morphology, and could be used as the indicators for anammox microbial survival ability and microbial aggregate morphology. Furthermore, slime secreted from anammox bacterial cells may be exhibited higher viscosity to the sludge surface and easily formed the gel network to aggregate. Large amounts of hydrophobic groups of protein in TB-EPS promoted the microbial aggregation. The mechanisms of anammox aggregation explored in this study enhanced the understanding of anammox stability in wastewater treatment processes.
A carbazole‐containing difluoroboron β‐diketonate complex (BCZ), which shows strong fluorescence in both the solid state and in organic solutions, is reported. The crystalline materials of BCZ ...obtained from different solvents display different emission colors. Single‐crystal analysis reveals that the enhanced overlap between adjacent molecules induces increased excited‐state delocalization and is responsible for the variation of the emission colors from yellow to red. The emission colors of the materials are effectively tuned by external stimuli such as grinding, heating, and solvent vapor. The powder X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and 1H NMR studies on materials of BCZ reveal that the thermochromic properties of BCZ are closely related to the removal of solvent molecules from the crystalline powders upon heating. Moreover, uniform 1D microstructures of BCZ obtained by solvent exchange in solution exhibit optical waveguide property with low optical loss.
A solid‐state fluorescent material based on carbazole‐containing BF2bdk complex (BCZ) is reported. The emission colors of BCZ in solid state are dependent on its molecular packing modes and are successfully tuned upon external stimuli, such as grinding, heating, and solvent fuming. The uniform microrod of BCZ exhibits optical waveguide properties with low optical loss.
•Difluoroboron β-diketonate dyes (BF2bdks) exhibit rich photophysical properties.•BF2bdks have shown wide application in various areas.•The basic chemistry and spectroscopic properties of BF2bdks are ...summarized.•Self-assembly and applications of BF2bdks are presented.
Difluoroboron β-diketonate complexes (BF2bdks) are highly luminescent organoboron complexes with several attributes such as strong fluorescence in both solution and solid state, large extinction coefficients, tunable fluorescent emission, and two-photon excited fluorescence. Some BF2bdks exhibit mechanochromic properties and room temperature phosphorescence (RTP) in solid state. Due to their rich photophysical properties, BF2bdks have shown wide applications in various areas. This review focuses on the basic chemistry and spectroscopic properties of BF2bdks in solution and solid state, as well as their self-assemblies and applications in biosensing, bioimaging and optoelectronic devices. A brief summary and outlook on BF2bdks chemistry are also included.
A new ring for your indole: An unprecedented copper‐catalyzed enantioselective Friedel–Crafts alkylation/N‐hemiacetalization cascade reaction with indoles and β,γ‐unsaturated α‐ketoesters is ...reported. This mild strategy provides new access to various synthetically and biologically important 2,3‐dihydro‐1H‐pyrrolo1,2‐aindoles in a highly enantioselective manner.
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