Bifunctional Groups Research Articles

High-Voltage Stable Perovskite Light-Emitting Diodes Enabled by an Optoelectric-Tunable Sandwiched Nanostructure.

While metal halide light-emitting diodes (PeLEDs) with unique optoelectronic properties are promising emitters for next-generation displays, their performance degrades rapidly due to severe ion migration during continuous operation, especially at high voltages. Here, we realize highly stable PeLEDs by designing inorganic dielectric/perovskite semiconductor emitter/organic dielectric sandwiched nanostructures to mitigate ion migration via regulating the electric field distribution. The bilateral cesium carbonate (Cs2CO3) and tetraoctylammonium bromide (TOAB) thin interlayers can not only largely reduce the voltage imposed on the perovskite layer by serving as series resistors and, thus, mitigate the ion migration but also regulate the charge carrier transfer to improve the radiative recombination efficiency. In addition, the underneath inorganic Cs2CO3 film also provides more heterogeneous nucleation sites for growing high-crystallinity perovskite crystals, while the atop TOAB with bifunctional groups (organic amino and Br- ions) refines the morphology and enhances the optical properties of the perovskite film. As a result, efficient and stable green PeLEDs based on such an optoelectric-tunable nanostructure exhibit extremely slow efficiency decay as the applied voltage increases, and the external quantum efficiencies were maintained over 10% at a high bias up to 20 V.

Doped double spirocyclic cationic POSS for nanocomposite anion exchange membranes with high conductivity and robustness

Organic-inorganic hybridization methods are receiving increasing attention as a method that can improve the performance of anion exchange membranes (AEMs) in a simpler and more effective way. Here, by selecting polyhedral oligomeric silsesquioxane (POSS) with good mechanical and thermal properties as inorganic fillers. Successful introduction of N-spirocyclic cations with bifunctional groups onto POSS yielded MDSU-poss. subsequently, we doped them into qPTP-IC-O-9% membranes as fillers in different ratios to obtain a series of composite membranes. High-density cations introduced by POSS with simultaneous organic-inorganic frameworks effectively inhibit membrane over-swelling. As a result, the membrane is able to achieve high ionic conductivity with the assurance of reasonable dimensional stability. At 80 °C, the 15 % MDSU-poss/qPTP-IC-O membrane achieved the ionic conductivity of 168.6 mS cm−1 at low SR with the peak power density of 431 mW cm−2. In addition, the mechanical properties of the composite membranes were all greatly improved due to the organic cations attached to the POSS with good affinity, contributing to the tensile strength of the 15 % MDSU-poss/qPTP-IC-O membrane of 57.4 MPa. The membrane was finally immersed in 3 M NaOH solution for 1032 h and still maintained 89.3 % of the starting ionic conductivity.

Liquid Metal Aerogel With Janus Architecture for Selective Direction Recognition and High‐Efficiency Moisture Energy Harvesting

AbstractLiquid metal (LM) micro‐nano droplets show the superiority in reducing the high surface tension applicable in conductive inks for flexible electronics. However, the dynamic surface makes LM droplets susceptible to be oxidized, facing challenges in storage and applications. Herein, a bifunctional groups cross‐linking strategy is adopted to encapsulate LM droplets into a robust shell. During sonicating LM in carboxymethyl chitosan (CMCS) solution with bifunctional groups (i.e., carboxyl and amino groups), a robust interface shell is constructed by anchoring effect, thereby providing high chemical stability (>7d). When directionally freezing‐drying LM dispersions, aerogel with Janus architecture is produced driven by the gravity of LM droplets. Due to the unique heterogeneous structure, the resultant aerogel exhibits a selective multifunctional response toward directional bending. In addition, owing to the gradient distribution of CMCS within aerogel, moisture electricity generator can be built with a high output voltage of 460 mV. Thus, this bifunctional groups cross‐linking strategy not only improves the chemical stability of LM micro‐nano droplets, but also renders a new method for producing multifunctional aerogel with energy harvesting and selective directional recognition, and applicable in smart sensors and power supplying devices.

Clickable Probes for Pathogen Proteasomes: Synthesis and Applications.

The 20S proteasome is a multimeric protease complex that is essential for proteostasis in the cell. Small molecule proteasome inhibitors are approved drugs for various cancers and are advancing clinically as antiparasitics. Although tools and technologies to study the 20S proteasome have advanced, only one probe is commercially available to image proteasome activity. This probe consists of a fluorescently labeled, peptidyl vinyl sulfone that binds to one or more of the catalytic proteasome subunits. Here, we synthesized two, active site-directed epoxyketone probes, LJL-1 and LJL-2, that were based on the peptidyl backbones of the anticancer drugs, carfilzomib and bortezomib, respectively. Each probe was conjugated, via click chemistry, to a bifunctional group comprising 5-carboxytetramethylrhodamine (TAMRA) and biotin to, respectively, visualize and enrich the 20S proteasome from protein extracts of two eukaryotic pathogens, Leishmania donovani and Trichomonas vaginalis. Depending on species, each probe generated a different subunit-binding profile by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), and the biotin tag enabled the enrichment of the bound subunits which were then formally identified by proteomics. Species differences in the order of electrophoretic migration by the β subunits were also noted. Finally, both probes reacted specifically with the 20S subunits in contrast to the commercial vinyl sulfone probe that cross reacted with cysteine proteases. LJL-1 and LJL-2 should find general utility in the identification and characterization of pathogen proteasomes, and serve as reagents to evaluate the specificity and mechanism of binding of new antiparasitic proteasome inhibitors.

A novel electroless nickel plating process for fabrication of optical fiber corrosion sensors

In this work, a novel silanization pre-treatment method has been successfully proposed to solve the problems of discontinuity and poor adhesion strength of electroless nickel plating using in the ultrasensitive optical fiber corrosion sensors. The chemically etched and hydroxylated optical fiber is simply treated with a mixed solution containing the hydrolyzed γ-APS with bifunctional group and PdCl2 before dipping into nickel plating solution. ATR-FTIR, AFM, SEM and theoretical calculations are applied to demonstrate the feasibility of the method and reaction mechanism. Results show that the –NH2 in γ-APS preferentially interacts with the Pd2+, while the Si-OH at the other end forms a covalent bond with the Si-OH on the optical fiber surface, forming a needle-like silane intercalation film by oriented adsorption. With this simple silanization pre-treatment method, a uniform and continuous electroless nickel plating can be successfully prepared. Our DFT calculations are good consistent with the experimental measurements.

Green Nanoengineered Fabrics: Waste-Derived Polyphenol-Zinc@ Silica Core-Shell Reactive Janus Nanoparticles for Functional Fabrics.

Fabricating Janus nanoparticle-functionalized fabrics with UV protection, strength enhancement, self-cleaning properties, and wash durability, with a biocompatible nature, is crucial in modern functional fabrics engineering. Particularly, tailoring multifunctional nanoparticles capable of exhibiting several distinct properties, utilizing low-cost raw materials, and adhering to green chemistry principles is pivotal. A fabrication strategy for developing multifunctional reactive Janus nanoparticles, utilizing waste-derived natural polyphenol (quercetin-3-glucuronide, myricetin-3-galactoside, gossypin, phlorizin, kaempferol, myricetin-3-arabinoside)-integrated zinc-silica core-shell Janus nanoparticles with UV protection, strength enhancement, and self-cleaning properties, is proposed. Polyphenols were utilized as sustainable precursors for synthesizing zinc-polyphenol complexes, which were then encapsulated within a silica shell to form a core-shell structure. Furthermore, Janus particles were created by introducing a bifunctional layer with half amine/carboxylic acid and half methyl terminals, imparting reactive hydrophilic and hydrophobic properties. Janus-coated textiles and leather exhibited significant attenuation of harmful UV radiation, with water contact angle measurements confirming improved water repellency. The coexistence of natural phenols and bifunctional groups within a material bolstered textile strength, fostering superior adhesion and markedly enhancing wash durability. This eco-friendly approach, utilizing waste-derived materials, presents a promising solution for sustainable textile engineering with enhanced performance in UV protection and water resistance, thereby contributing to the advancement of green nanotechnology in textile applications.

Solid polymer electrolytes regulated by ion-dipole interactions for high voltage lithium batteries

Solid polymer electrolytes (SPEs) with wide electrochemically stable window and high lithium-ion transference number (tLi+) are a requirement for high energy density lithium batteries. Here, we construct a copolymer electrolyte (PDA) with ether-ester bifunctional groups that exhibits a low highest occupied molecular orbital (HOMO) energy level by in situ polymerization. Compared to the poly(1,3-dioxolane) (PDOL) pure polyether electrolyte, the weakening of the ion-dipole interaction between lithium salt and polymer in the PDA electrolyte promotes the formation of a “weak solvation” structure. Therefore, the electrolyte achieves high oxidative stability (4.6 V vs. Li+/ Li with a standard leakage current of 10 μA), high Li+ transference number (0.60), and importantly, derives a stable LiF-rich composition on high voltage cathode surface. Which ultimately enables stable cycling of Li||LiNi0.5Co0.2Mn0.3O2 (NCM523) batteries at a range of 3.0–4.3 V. This work provides a fundamental understanding of the design of antioxidant SPEs to achieve high energy density lithium batteries.

Bifunctional hyper-cross-linked polymer with phosphorylated-amidoximated groups for efficient uranium extraction from water

Designing and developing a uranium adsorbent with high adsorption capacity and good selectivity is highly significant. We synthesized a novel hyper-cross-linked polymer adsorbent with bifunctional groups, (PHCP-4-AO), such as phosphate and amidoxime groups, via simple Scholl reaction and subsequent functionalization for the first time highly efficient extraction of U(VI) from aqueous solution. Due to its unique molecular structure design, it can enhance the selectivity and adsorption capacity of uranium by using two different functional groups. The maximum uranium adsorption capacity of PHCP-4-AO was 424.33 mg/g, which was higher than the single-functional group phosphorylated (PHCP-4) (315.43 mg/g) and amidoximated (HCP-4-AO) (260.38 mg/g) adsorbents. The combination of phosphate and amidoxime groups improves the adsorption effect. PHCP-4-AO has good selectivity and affinity for uranyl ions. In simulated wastewater, the Kd of PHCP-4-AO for uranium was 7266.3 mL/g, which was more than 15 times that of other ions. After three adsorption–desorption cycles, the adsorption capacity of PHCP-4-AO can still be maintained above 300.00 mg/g. Through XPS analysis, it is speculated that the sorption of uranium by PHCP-4-AO is owing to the lone pair electrons found on the oxygen atom of the phosphate groups, as well as the oxime oxygen and amino nitrogen atoms of the amidoxime groups entering the uranium’s empty orbit to form the coordination bonds. These findings demonstrated that this new hyper-cross-linked polymer could be considered as a valuable material in the extraction and recovery of uranium from uranium-containing aqueous solutions.

Phosphonate Diacid Molecule Induced Crystallization Manipulation and Defect Passivation for High‐Performance Inverted MA‐Free Perovskite Solar Cells

AbstractInverted perovskite solar cells (PSCs) comprising formamidinium‐cesium (FA‐Cs) lead triiodide have garnered considerable attention due to their impressive efficiency and remarkable stability. Nevertheless, synthesizing high‐quality FA‐Cs alloyed perovskite films presents challenges, primarily attributable to the intricate interphase process involved and the absence of methylammonium (MA+) and mixed halogens. Here, the additive 3‐phosphonopropanoic acid (3‐PPA) is introduced, with bifunctional phosphonic acid groups, into the perovskite precursor to modulate the crystal growth and provide passivation at grain boundaries. In situ characterization reveals that the 3‐PPA can form a “rapid nucleation, slow growth” mechanism, resulting in perovskite films with enlarged grains and enhanced crystallinity. In addition, 3‐PPA serves to passivate grain boundary defects and release residual strain by forming molecular bridging, leading to the passivated films achieving a fluorescence lifetime of 5.79 microseconds with a favorable n‐type contact interface. As a result, the resulting devices incorporating 3‐PPA achieve a champion power conversion efficiency (PCE) of 24.05% and an ultra‐high fill factor (FF) of 84.22%. More importantly, the optimized devices exhibit satisfactory stability under various testing conditions. The findings underscore the pivotal role of multifunctional additives in crystallization control and defect passivation for high‐performance MA‐free and pure iodine PSCs.

Structural modulation of covalent organic frameworks based on redox active center of π-conjugated amine unit for enhanced electrochromic properties

The covalent organic frameworks (COFs) possess high designability, which provides a platform for synthesizing novel optoelectric materials, including electrochromic materials. In this work, N,N,N′,N′-tetra-(4-aminophenyl)-1,4-phenylenediamine (TPDA) with π-electron conjugate system and redox active centers was used as the main building block. The 4,4′-biphenyl diformaldehyde (BDA) and the 2,2′-thiophene-5,5′-diformaldehyde (TDA) were used as the aldehyde building units. Two imine-based COF electrochromic active materials (COFTPDA-BDA and COFTPDA-TDA) were prepared by Schiff base reaction. The test results reveal that COFTPDA-TDA has superior electrochromic properties than COFTPDA-BDA. Their contrasts are 0.46 and 0.40, and the coloring/fading times are 3.1/10.6 s and 10.9/14.3 s, respectively. The COFTPDA-TDA material possessing a bifunctional group structure was synthesized by replacing the biphenyl group with the bithiophene group with redox activity, which can enhance the optical properties and inter-layer π-π conjugation. Besides the electrochromic properties, the morphology and crystal lattice parameters are different. Therefore, it is expected to develop COFs-based electrochromic materials with rich colors, excellent performance, and wide application by introducing construction units with different redox active centers.

Pore structure and N/F bifunctional groups in hierarchical porous carbons via spontaneous silica etching for enhanced capacitive deionization performance

This study presents a novel, one-step synthesis of nitrogen and fluorine bifunctional hierarchical porous carbons (HPCs) for capacitive deionization (CDI). The method involves co-gelation of silica and polyvinylidene fluoride, followed by pyrolysis for efficient silica removal. This method eliminates the need for toxic solvents and extensive cleaning steps. Optimized HPCs exhibit a high surface area (1464.71 m2/g) with abundant mesopores. Electrochemical analysis reveals a specific capacitance of 179.5F/g. In the CDI process using 500 mg/L NaCl solution, the HPCs demonstrate exceptional performance with a high salt adsorption capacity (24.61 mg/g) and a fast average adsorption rate (3.69 mg/g/min). This performance is attributed to the combined effects of the hierarchical pore structure facilitating rapid ion adsorption and the N/F bifunctional groups enhancing electrosorption ability. This work offers a one-step, solvent-free method for synthesizing HPCs with superior desalination performance and demonstrates the synergistic effect of pore structure and N/F bifunctional groups.

Synthesis of Stable and Efficient Electrocatalysts for Hydrogen Evolution: Hierarchical NiMo-Based Hollow Nanotubes

Large-scale development of low-cost, efficient, and stable powder electrocatalysts for the hydrogen evolution reaction (HER) in alkaline solutions is a key step toward commercial hydrogen production. Herein, a hierarchical NiMo-MoO3-x hollow nanotube (NiMo-MoO3-x-HNT) with bifunctional groups as an efficient HER electrocatalyst was strategically invented using an MoO3 nanorod (MoO3−NR) as the precursor. The synthesis mechanism of the NiMo-MoO3-x-HNT is established based on in-depth investigations using diffraction, spectral, and microscopy results. Experimental results suggest that the NiMo-MoO3-x-HNT exhibits excellent electrocatalytic HER performance in 1 M KOH, with a low overpotential of 26.5 mV@10.0 mA cm-2 and a small Tafel slope of 32.6 mV dec–1. These values are comparable to those of cutting-edge electrocatalysts based on platinum-group metals. Moreover, it exhibits an almost unaffected cyclic stability over 50,000 cycles and robust durability over 98 h. This remarkable performance is attributed to its bifunctional groups and the porous hierarchical hollow nanotubular morphology. In summary, this study proposes a novel, efficient, and cost-effective strategy for the development of noble metal-free, high-performance HER electrocatalysts.

A Synergistic Bimetallic Ti/Co-Catalyzed Isomerization of Epoxides to Allylic Alcohols Enabled by Two-State Reactivity.

Isomerization of epoxides into versatile allylic alcohols is an atom-economical synthetic method to afford vicinal bifunctional groups. Comprehensive density functional theory (DFT) calculations were carried out to elucidate the complex mechanism of a bimetallic Ti/Co-catalyzed selective isomerization of epoxides to allyl alcohols by examining several possible pathways. Our results suggest a possible mechanism involving (1) radical-type epoxide ring opening catalyzed by Cp2Ti(III)Cl leading to a Ti(IV)-bound β-alkyl radical, (2) hydrogen-atom transfer (HAT) catalyzed by the Co(II) catalyst to form the Ti(IV)-enolate and Co(III)-H intermediate, (3) protonation to give the alcohols, and (4) proton abstraction to form the Co(I) species followed by electron transfer to regenerate the active Co(II) and Ti(III) species. Moreover, bimetallic catalysis and two-state reactivity enable the key rate-determining HAT step. Furthermore, a subtle balance between dispersion-driven bimetallic processes and entropy-driven monometallic processes determines the most favorable pathway, among which the monometallic process is energetically more favorable in all steps except the vital hydrogen-atom transfer step. Our study should provide an in-depth mechanistic understanding of bimetallic catalysis.

Novel magnetic porous organic polymer containing amino and triazine bifunctional groups for efficient adsorption of nitroimidazoles

In this paper, a novel magnetic hyper-crosslinked polymer with amino and triazine bifunctional groups (M-NH2-THCP) was developed. M-NH2-THCP has strong nitroimidazoles (NDZs) enrichment effect, and therefore it was used as an adsorbent to extract five NDZs from lake water, catfish and shrimp meat prior to HPLC. Polar interaction, π-π stacking interaction, hydrogen bond and Lewis acid-base interaction were attested to be the major adsorption mechanism. The method has a good linearity in the range of 0.1–100 ng mL−1 for lake water, 10–400 ng g−1 for catfish and shrimp muscle with R2 > 0.9964. The limits of detection of NDZs were 0.03–0.04 ng mL−1 for lake water, 1.0–2.0 ng g−1 for catfish and 2.0–2.5 ng g−1 for shrimp, which is superior to most reported method. The method recoveries were 87.6–119 %, and relative standard deviations were less than 8.7 %. M-NH2-THCP holds great application potential in pollutants enrichment, separation and removal.

Regulating the continuous and concentrated distribution of Quasi-2D perovskite phases to achieve Sky-Blue Light-Emitting diodes with efficiency approaching 17%

Blue perovskite light-emitting diodes (PeLEDs) are increasingly crucial for manufacturing high-definition full-color displays due to their outstanding electroluminescent properties. Quasi-two-dimensional (quasi-2D) perovskite stands out as the most promising material for blue light-emitting layer, given its robust quantum/dielectric confinement. In this study, we present the preparation of PeLEDs with a tunable blue emission wavelength using pure bromide perovskite components by adjusting the content of halogenated organic ammonium bromide [2-bromoethylamine hydrobromide (BEABr)]. The bifunctional ligand BEABr not only achieves an excellent phase distribution of quasi-2D perovskite but also reduces the weak van der Waals gap between individual perovskite layers, facilitating effective energy transfer in perovskite films. Additionally, the bifunctional groups passivate perovskite defects and inhibit phase separation, leading to efficient and stable sky-blue luminescence. The BEABr-doped sky-blue PeLED demonstrated superior device performance, achieving a maximum external quantum efficiency of 16.98 % at 493 nm. This work serves as inspiration for further exploration of efficient and stable commercial blue PeLED devices.

Bifunctional lignocellulose nanofiber hydrogel possessing intriguing pH-responsiveness and self-healing capability towards wound healing applications

Lignocellulose nanofibers (LCNF) obtained from agricultural waste are potential candidates for enhancing composite materials because of their excellent mechanical properties, abundant groups and high biocompatibility. However, the application of LCNF has received limited attention to date from researchers in the healthcare field. Herein, based on the bifunctional group (carboxyl and aldehyde groups) modified LCNF (DCLCNF) and chitosan (CS), we developed a multifunctional bio-based hydrogel (CS-DCLCNF). The addition of lignin-containing DCLCNF strengthened the internal crosslinking and the intermolecular interaction of hydrogels, and the presence of lignin and carboxyl groups increased the mechanical strength of the hydrogel and the adsorption of aromatic drugs. Results revealed that the hydrogels exhibited self-healing, injectable, and high swelling rates. The hydrogels had favorable mechanical strength (G'max of ~16.60 kPa), and the maximum compressive stress was 24 kPa. Moreover, the entire tetracycline hydrochloride (TH) release process was slow and pH-responsive, because of the rich noncovalent and π–π interactions between DCLCNF and TH. The hydrogels also exhibited excellent biocompatibility and antibacterial properties. Notably, the wound healing experiment showed that the hydrogels were beneficial in accelerating wounds healing, which could heal completely in 13 days. Therefore, CS-DCLCNF hydrogels may have promising applications in drug delivery for wound healing.

Fluorescence-plane polarization for the real-time monitoring of transferase migration in living cells.

Transferases are enzymes that exhibit multisite migration characteristics. Significantly, enzyme activity undergoes changes during this migration process, which inevitably impacts the physiological function of living organisms and can even lead to related malignant diseases. However, research in this field has been severely hindered by the lack of tools for the simultaneous and differential monitoring of site-specific transferase activity. Herein, we propose a novel strategy that integrates a fluorescence signal response with high sensitivity and an optical rotation signal response with superior spatial resolution. To validate the feasibility of this strategy, transferase γ-glutamyltransferase (GGT) was used as a model system to develop dual-mode chiral probes ACx-GGTB (AC17-GGTB and AC15-GGTB) using chiral amino acids as specific bifunctional recognition groups. The probes undergo structural changes under GGT, resulting in the release of bifunctional recognition groups (chiral amino acids) and simultaneously generate fluorescence signals and optical rotation signals. This dual-mode output exhibits high sensitivity and facilitates differentiation of sites. Furthermore, it enables simultaneous and differential detection of GGT activity at different sites during migration. We anticipate that probes developed based on this strategy will facilitate imaging-based monitoring of the activity for other transferases, thus providing an imaging platform suitable for the real-time tracking of transferase activity changes during migration.

Sucralose with bifunctional groups as a functional additive enhancing the interfacial stability of zinc metal anodes via interfacial molecular chemistry regulation

Sucralose is proposed as a functional electrolyte additive to regulate the solvation structure of Zn2+ near the interface of electrode/electrolyte for inhibiting dendrite formation and facilitating uniform Zn metal plating.

In situ bifunctional solid acids bearing B–OH and –COOH groups for efficient hydrolysis of cellulose to sugar in a pure aqueous phase

Pyruvaldehyde as a carbon source is synthesized together with boric acid to produce a carbon-based solid catalyst with in situ bifunctional groups, which is utilized to induce the hydrolysis of cellulose to sugar in a pure aqueous phase.

Synthesis, Characterization, and Evaluation of Antioxidant and Physical Properties of New Bifunctional Aromatic Monomers Containing Imine and Heterocyclic Rings in The Main Chain.

New various monomers with di amine functional groups have been synthesized, containing di azomethine or di seven-membered heterocyclic rings in the backbone. A condensation reaction of benzidine with 4-amino benzaldehyde with some drops of glacial acetic acid in ethanol absolute prepared bi-functional amino groups monomer with azomethine core P1(4-[(1E)-[4[4-(E)-(4-aminophenyl)methylidene]amino]phenyl}phenylimino methyl aniline). The next step was the Cycloaddition reaction of P1 with succinic, malic, and phthalic anhydrides used to obtain aromatic heterocyclic monomers with oxazepane and oxazepine rings containing lactone and lactam groups. All the synthesized monomers were characterized spectrally with many techniques (FT.IR,1 H1.NMR, C13-NMR) that were used to investigate the functional groups in the structure of monomers. Monitoring the progress and completion of the reaction was performed using thin-layer chromatography (TLC). Physical characterizations, including detecting the melting point, purity, colour, retardation factor, molecular formula, and molecular weight, the polarized optical microscope (POM) used for Image-based microscopic interpretation of prepared compounds. All the prepared monomers are considered effective antioxidant agents as they give free radicals scavenging over 60%, reaching 80 %; this activity makes them useful in large numbers of industries as they can scavenge the free radicals that the industrial product may be exposed, which increases its shelf life and enhance its effectiveness.