Modification Of Functional Groups Research Articles

Construction of aldehyde-based, ester-based hyper-cross-linked polar resin and its selective adsorption mechanism for phenol in coal chemical wastewater

Efficient and precise recovery of phenol from coal chemical wastewater (CCW) poses a significant challenge, prompting the development of a novel aldehyde-based, ester-based hyper-cross-linked polar resin (DES–COOC–CHO) in this study. Two distinct functional group modification methods were employed to enhance the screening effect of the resin. SEM, FT-IR, NMR, XPS, and BET characterizations confirmed the successful construction of the hyper-cross-linked polar resin, incorporation aldehyde and ester groups, exhibiting a special surface area of 627.2 m2/g and a microporous specific surface area percentage of 29.94%. DES–COOC–CHO adhered to the pseudo-second-order kinetic model and Langmuir model (maximum adsorption capacity of 118.0 mg/g). Its adsorption of phenol was spontaneous chemisorption, monolayer adsorption. Notably, even after undergoing 20 adsorption–desorption cycles, the resin maintained a stable adsorption capacity, showcasing excellent recoverability. In the presence of phenols sharing similar properties, DES–COOC–CHO exhibited superior selectivity for phenol. In real CCW, it achieved a remarkable 90% selective removal rate of phenol. The primary selective mechanism relied on the hydrogen bonding effect facilitated by aldehyde and ester groups, coupled with microporous sieving of appropriate size. In comparison with other adsorbent materials, DES–COOC–CHO exhibited superior adsorption properties, coupled with a cost-effective preparation process, presenting significant potential for practical applications.

Efficient construction of high-quality sulfonated porous aromatic frameworks by optimizing the swelling state of porous structures.

Conventional post-modification methods usually face the fundamental challenge of balancing the high content of functional groups and large surface area for porous organic polymers (POPs). The reason, presumably, stems from ineffective and insufficient swelling of the porous structure of POP materials, which is detrimental to mass transfer and modification of functional groups, especially with large-sized ones. It is important to note that significant differences exist in the porous structures of POP materials in a solvent-free state after thermal activation and solvent swelling state. Herein, we propose that the improvement of the swelling state of the porous structure of POP materials is more conducive to obtaining high-quality sulfonated POP materials, and employ a one-pot modification strategy for preparing sulfonated porous aromatic frameworks (PAFs) to prove the proposal. These results show that the specific surface area of the resulting polymer is 580 m2 g-1 with a sulfur content of up to 13.2 wt%, which is superior to most sulfonated porous materials and the control sample. More importantly, we have also shown that the same conclusion is reached by performing similar treatments on hyper-crosslinked polymers (HCPs) and conjugated microporous polymers (CMPs), proving that our hypothesis is effective and feasible when compared to the conventional post-sulfonation method. The excellent hydrophilicity, rich content of sulfonic acid groups, high specific surface area and hierarchical pore structure make the resulting polymer an ideal adsorbent for micro-pollutants in water. The maximum adsorption capacities for Rhodamine B (RhB), Methylene Blue (MB), Tetracycline (TC) and Ciprofloxacin (CIP) are 1075 mg g-1, 1020 mg g-1, 826 mg g-1 and 1134 mg g-1, respectively. This study not only demonstrates the preparation of efficient sulfonated porous adsorbents for the efficient removal of cationic dyes and antibiotics but also illustrates an effective method for constructing high-quality functional POP materials by optimizing the swelling state of the porous structure.

Synthesis and structural confirmation of selaginpulvilin X.

We report the first total synthesis of the natural product selaginpulvilin X, a selaginellaceae polyphenol class of compounds. Our synthetic strategy employs cross-coupling reactions and an organolithium addition to construct the carbon framework. Subsequently, the functional group modifications and deprotection yield the natural product. Spectral analysis confirms the proposed structure by comparing natural and synthetic samples.

Metal-free functionalization of tyrosine residues in short peptides and study of the morphological alterations.

An efficient functionalization of tyrosine residues in phenolic regions is achieved under metal-free conditions. The strategy involves the conversion of a tyrosine residue to 4-amino phenylalanine or 4-amino-3-methoxy phenylalanine in short peptides through a controlled oxidative dearomatization. This transformation is achieved in one pot with good yields and excellent regioselectivity. Consequently, the self-assembly of the peptide compounds has been studied at the nanoscopic level before and after functionalization. The results suggest that the peptide derivatives comprising amide groups promote intermolecular H-bonding interactions and the difference in -OH and -NH2 functional groups is found to be responsible for the morphological changes. Morphological transitions from 1D nanowires to 2D nanosheets were observed during functional group modification.

Polyether-based polyurethane electrolyte for lithium metal battery: a perspective.

Polyurethane (PU)-based electrolyte has become one of the most important research directions because of its unique repeating 'soft-hard' segment co-polymer structure. Its 'soft segment' composition includes polyethylene oxide, polysiloxane, polycarbonate, cellulose and polyether. Among them, polyether-based polyurethane electrolytes (PPES) have the advantages of simple synthesis, molecular structure optimization and functional group modification, which can greatly improve the ionic conductivity of the system and form a good ion transport interface. To date, a few separate and detailed reviews of advances in PPES have been reported. In this paper, the research progress of PPES is reviewed from the aspects of structural design strategy, molecular synthesis, conductivity modification methods, specific functions and interfacial ion transport behavior in lithium metal batteries (LMBs). In addition, the synthetic route of PPES and the development prospect of PPES are discussed. We also provide guidance for developing high-performance PPES for next-generation LMBs.

ReaxFF molecular dynamics of graphene oxide/NaCl aqueous solution interfaces.

In this work, the interaction of NaCl aqueous solution with graphene (G), graphene oxide (GO), and graphite oxide (GTO) is studied using the ReaxFF module of Amsterdam Modeling Suite (AMS) software. We consider four models using the NaCl aqueous solution, containing a graphene sheet (G), a single sheet of GO with epoxide and hydroxyl groups on its surface, 4 layers of GO to model GTO, and a bulk NaCl solution as a reference. The structural and dynamical properties of G, GO, and GTO were quantified by analyzing the functional groups, radial distribution functions, density profiles and diffusivities of water and ions. Due to the reactive force field, the systems underwent spontaneous modification of surface functional groups during the first 750 ps after which the structure stabilizes (the energy stabilizes in less than 400 ps). Pristine graphene in contact with the NaCl solution formed hydroxyl groups on the edges, i.e., converted to partially reduced graphene oxide. The epoxy groups (Oe) on the initial GO were rather unstable, leading to a reduction of their number, however, there was an increase in the number of hydroxyl groups (Oh), mainly at the edges. The interactions of NaCl with the carbon-based sheets are rather weak, including GO and GTO which are decorated with numerous functional groups. Diffusion coefficients of water agree with the available data, but discrepancies in Na+ and Cl- diffusivity compared to other references underscore the need for further development in the dynamic parameters of the reactive force field used. In essence, our research provides specific data previously unreported, laying a foundation for advancing water desalination system design. The study's novelty lies in its realistic approach to graphene/graphene oxide modification, comprehensive characterization, and the application of the reactive force field to explore the graphene oxide-NaCl aqueous interface, contributing to the development of a practical membrane system for water desalination.

Temperature dependence of MXenes plasmons induced hot carrier generation and transport

Unlike conventional optoelectronic devices, plasmon-driven optoelectronic devices can efficiently realize energy conversion and regulate the energy distribution of hot carriers through high-energy, non-equilibrium “hot” electron-hole pairs (hot carriers) generated by surface plasmon non-radiative decay, thereby presenting new opportunities for realizing hot carrier optoelectronic devices. As the basis for the practical application of plasmon optoelectronic devices, searching for plasmon metal materials with exceptional performance has always been an important topic in the field of hot carrier optoelectronic devices. Currently, MXenes can be synthesized on a large scale and has excellent photoelectric properties, so it can be used to build a variety of hot carrier photodetectors with unique structures and functions. Unlike the fixed surface ends of two-dimensional materials such as graphene, MoS<sub>2</sub> and borophene, MXenes has an abundance of surface functional groups. However, the increase of ambient temperature will accelerate the oxidation modification of surface functional groups, thus affecting the life and performance stability of optoelectronic devices. In view of the inherent limitations of experimental research on dynamic characteristics of hot carriers at continuous temperatures, we study the temperature effects on the electronic state distributions and scattering effects by using the theory of multi-body perturbation and quantum mechanics. Particularly, we introduce temperature effect into interband electron transition and phonon-assisted electron transition process to obtain temperature dependent dielectric function. From the perspective of non-radiative decay of surface plasmon, we quantify the hot carrier generation efficiency, energy distribution and transport characteristics by first principles calculations, in order to systematically study the ambient temperature dependence of plasmon-induced hot carriers in MXenes. The results show that the interband transition and the phonon-assisted electron transition in MXenes together efficiently produce high-energy hot hole-dominated carriers with a long lifetime and transport distance, which is comparable to borophene. The increase of ambient temperature significantly improves the hot carrier generation efficiency in the infrared range. Meanwhile, the physical mechanism of hot carrier generation in visible light is almost unaffected by the increase of ambient temperature, and the generated hot holes show excellent ambient temperature stability. In addition, the lifetime and transport distance of hot carriers decrease with ambient temperature increasing, which is mainly due to the enhanced scattering of electrons and optical phonons. The research results will provide theoretical and data support for quantitatively evaluating the ambient temperature stability of MXenes plasmon optoelectronic devices in practical environment.

Transcriptome analysis reveals diverse Curvularia tsudae strategies in response to cadmium stress

Cadmium (Cd) is a highly toxic heavy metal that poses significant threats to living organisms. Curvularia tsudae has demonstrated remarkable survival capabilities in the presence of high Cd concentrations, exhibiting its exceptional Cd tolerance. Although some physiological studies have been conducted, the molecular mechanisms underlying Cd tolerance in C. tsudae is largely unknown. In this study, a comparative transcriptome analysis was performed to explore the molecular mechanisms of C. tsudae under Cd stress. Among the 10,498 identified unigenes, 2526 differentially expressed genes (DEGs) were identified between the Cd-free and Cd-treated samples. Functional annotation and enrichment analysis of these DEGs identified several key biological processes involved in coping with Cd stress. Genes related to cell wall modification and organic acid metabolism contributes to Cd binding or chelation. Fourier transform infrared spectroscopy (FTIR) analysis further highlighted the modifications in functional groups with the cell wall under Cd stress. Furthermore, the transporters tended to be modulated in response to Cd stress, and up-regulated genes involved in antioxidants likely contributes to high Cd tolerance. The processes from DNA to protein metabolism appeared to responsive to the presence of Cd stress as well. These results contribute to the advance of the current knowledge about the response of C. tsudae to Cd stress and lay the foundation for further advancements in using fungi for the remediation of Cd-polluted environments.

D-Ring Modifications of Tetracyclines Determine Their Ability to Induce Resistance Genes in the Environment.

The widespread utilization of tetracyclines (TCs) in agriculture and medicine has led to the borderless spread of tetracycline resistance in humans, animals, and the environment, posing huge risks to both the ecosystem and human society. Changes in the functional group modifications resulted in a higher bacteriostatic efficacy of the new generation of TCs, but their effect on the emergence and evolution of antibiotic resistance genes (ARGs) is not yet known. To this end, four TCs from three generations were chosen to compare their structural effects on influencing the evolution of ARGs in soil microbial communities. The findings revealed that low-generation TCs, such as tetracycline and oxytetracycline, exhibited a greater propensity to stimulate the production and proliferation of ARGs than did high-generation tigecycline. Molecular docking analysis demonstrated that modifications of the D-ring functional group determined the binding capacity of TCs to the substrate-binding pocket of transcriptional regulators and efflux pumps mainly involved in drug resistance. This can be further evidenced by reverse transcription-quantitative polymerase chain reaction quantification and intracellular antibiotic accumulation assessment. This study sheds light on the mechanism of the structural effect of antibiotic-induced ARG production from the perspective of compound-protein binding, therefore providing theoretical support for controlling the dissemination of antibiotic resistance.

Synthesis of Waixenicin A: Exploring Strategies for Nine-Membered Ring Formation.

We present a comprehensive account on our efforts behind the recently published synthesis of waixenicin A. Our approach for constructing the dihydropyran ring relied on an Achmatowicz rearrangement. For the assembly of the nine-membered ring, four distinct strategies were investigated. Our initial attempts using radical-based addition/fragmentation reactions targeting the C7-C11 bond proved unsuitable for accessing the 6/9-bicycle. By employing anionic fragmentation conditions at the furfuryl alcohol stage, we successfully reached a 5/9-bicycle. However, subsequent ring-expansion was unsuccessful. Alternative approaches, such as Nozaki-Hiyama-Kishi or Heck reactions to connect the C6-C7 bond, also encountered difficulties, with no nine-membered ring formation observed. Our first breakthrough came from our attempts to install the C5-C6 bond via an intramolecular alkylation. Surprisingly, subsequent functional group modifications proved unexpectedly challenging, necessitating a redesign of our synthetic route. Drawing from all our investigations, we concluded that construction of the C9-C10 bond would enable efficient nine-membered ring alkylation and would facilitate the installation of the desired substitution pattern along the southern periphery. Exploration of this strategy yielded further surprises but ultimately led to the successful synthesis of waixenicin A and 9-deacetoxy-14,15-deepoxyxeniculin. For the latter compound, a bioinspired one-step rearrangement to xeniafauranol A was achieved.

Coffee charcoal as a green catalyst for oxidative dehydrogenation

Nitrogen heterocyclic (N-heterocyclic) compounds are extensively present in natural products and active drug molecules. However, their synthesis typically requires the use of noble metal catalysts and harsh conditions. In this study, we report a novel approach using coffee charcoal as a green catalyst for the mildly mechanically driven oxidative dehydrogenation of N-heterocyclic compounds. A one-step strategy was employed to construct a microporous coffee charcoal catalyst with C defects, in-situ co-doping of multi-atoms (N, O), and abundant modification of functional groups (–OH and –COOH). Under room temperature and with H2O as solvent, the coffee charcoal catalyst demonstrates a high yield of approximately 94 % and allows for gram-scale reactions with H2O being the only by-product. Moreover, the catalyst exhibits excellent reusability, maintaining its activity for over 13 cycles. Results indicate that the defects and atom doping can enhance the adsorption of O2, which is then activated to singlet oxygen (1O2) through the conversion of –OH functional groups on the catalyst’s surface. The singlet oxygen (1O2) can strengthen the oxidative dehydrogenation of N-heterocyclic compounds. Furthermore, the mechanically driven technique both activates the reaction interface and supplies the necessary reactive energy, thus providing a comprehensive explanation for the mild reaction conditions observed. In conclusion, our research proposes a sustainable and environmentally friendly method for the oxidative dehydrogenation of N-heterocyclic compounds, which can drive crucial reactions with significant relevance to sustainability.

Bubble Management for Electrolytic Water Splitting by Surface Engineering: A Review.

During electrocatalytic water splitting, the management of bubbles possesses great importance to reduce the overpotential and improve the stability of the electrode. Bubble evolution is accomplished by nucleation, growth, and detachment. The expanding nucleation sites, decreasing bubble size, and timely detachment of bubbles from the electrode surface are key factors in bubble management. Recently, the surface engineering of electrodes has emerged as a promising strategy for bubble management in practical water splitting due to its reliability and efficiency. In this review, we start with a discussion of the bubble behavior on the electrodes during water splitting. Then we summarize recent progress in the management of bubbles from the perspective of surface physical (electrocatalytic surface morphology) and surface chemical (surface composition) considerations, focusing on the surface texture design, three-dimensional construction, wettability coating technology, and functional group modification. Finally, we present the principles of bubble management, followed by an insightful perspective and critical challenges for further development.

Effect of functionalization on thermal conductivity of hexagonal boron nitride/epoxy composites

Electronic equipment generates a significant amount of heat during operation with the trend of integrated circuit chips and electronic components towards miniaturization and multi-functionality. Consequently, guaranteeing safe and dependable functioning while appropriately dispersing heat has become a critical challenge in the development of the microelectronics sector. The emergence of thermal interface materials (TIMs) with high thermal conductivity can effectively address this issue. In this study, simulations and experiments were used to investigate the effects of functional groups, including hydroxyl (-OH), dopamine (DA) and silane coupling agent (KH550), and their grafting ratios on the thermal conductivity of hexagonal boron nitride/epoxy (h-BN/EP) composites. The interface thermal conduction results demonstrated that the modification of functional groups with a higher grafting ratio exhibited a larger enhancement, and KH550 outperformed DA and -OH in terms of the enhancing effect. Moreover, according to the effective medium theory (EMT), the simulated thermal conductivity of BN-KH550/EP composite (2 % grafting ratio of KH550, 10 vol% filling ratio of BN) was 0.692 W·m−1·K−1, 224.9% higher than that of pure epoxy resin. Additionally, the experimentally measured thermal conductivity was 0.703 W·m−1·K−1, showing good agreement with the simulation result and indicating EMT's accurate prediction for the h-BN/EP composites.

Tiny Windows in Reticular Nanomaterials for Molecular Sieving Gas Separation Membranes

AbstractThe current state of reticular chemistry enables the synthesis of a wide range of highly porous nanomaterials for gas separation, including metal‐organic frameworks (MOFs), covalent organic frameworks (COFs), porous organic cages (POCs), metal‐organic cages (MOCs), and polyhedra (MOPs). This perspective focuses on membrane technology, a key player in energy‐efficient gas separations. It explores the world of reticular materials, taking a glance at tiny pore windows with narrow openings, which are ideal for high‐resolution molecular sieving, and how to design them. Promising concepts in this field are membranes consisting of neat materials, but also mixed matrix membranes, where polymeric films incorporate reticular fillers, creating cost‐efficient membranes. This article sheds light on the potential use of reticular materials as membrane components. The reticular synthesis of MOFs offers the ability to separate gas molecules with minimal size differences effectively. For COFs, the crucial factor lies in reducing their pore size, preferably through functional group modifications. Porous cage compounds can achieve fine distribution from homogeneous dispersions into polymers making them excellent candidates for mixed matrix membranes. This perspective provides strategies and guiding principles for the future of reticular nanomaterials‐based membranes, addressing the pressing need for advanced and efficient separation technologies.

An integrated experimental and computational investigation of N,9,10-trihydroxyoctadecanamide as a potential collector for the flotation separation of fluorite and calcite

Hydrofluoric acid production heavily depends on fluorite (CaF2), a mineral frequently occurring alongside other calcium-rich minerals such as calcite (CaCO3). To separate fluorite from calcite and other associated minerals, flotation is the primary method employed. Oleic acid serves as the most commonly used collector in fluorite flotation. However, oleic acid exhibits poor selectivity and limited solubility at low temperatures. A novel fluorite flotation collector, N,9,10-trihydroxyoctadecanamide (THODA), is developed through the modification of the polar functional group of oleic acid, carboxyl, to an N-hydroxy amide group. Additionally, two hydroxy groups are introduced at the double bond position of oleic acid. Flotation experiments demonstrate that employing THODA as a collector can yield a fluorite recovery of approximately 90%, while the recovery rate of calcite ranges between 10% and 20%. THODA exhibits a superior selectivity in the flotation separation of fluorite and calcite compared to oleic acid. Zeta potential experiments reveal that following the treatment with oleic acid, the zeta potential of calcite surface rapidly decreases, whereas after the treatment with THODA, the zeta potential of calcite surface decreases to a lesser extent. This suggests that, under identical dosage conditions, THODA adsorbs less onto calcite surface compared to oleic acid. Consequently, THODA exhibits a weaker ability to collect calcite in comparison to oleic acid, thereby resulting in its enhanced selectivity over oleic acid.

In vitro cytotoxic effect of stigmasterol derivatives against breast cancer cells

BackgroundStigmasterol is an unsaturated phytosterol that belong to the class of tetracyclic steroids abundant in Rhoicissus tridentata. Stigmasterol is an important constituent since it has shown impressive pharmacological effects such as anti-osteoarthritis, anticancer, anti-diabetic, anti-inflammatory, antiparasitic, immunomodulatory, antifungal, antioxidant, antibacterial, and neuroprotective activities. Furthermore, due to the presence of π system and hydroxyl group, stigmasterol is readily derivatized through substitution and addition reactions, allowing for the synthesis of a wide variety of stigmasterol derivatives.MethodsStigmasterol (1) isolated from Rhoicissus tridentata was used as starting material to yield eight bio-active derivatives (2–9) through acetylation, epoxidation, epoxide ring opening, oxidation, and dihydroxylation reactions. The structures of all the compounds were established using spectroscopic techniques, NMR, IR, MS, and melting points. The synthesized stigmasterol derivatives were screened for cytotoxicity against the hormone receptor-positive breast cancer (MCF-7), triple-negative breast cancer (HCC70), and non-tumorigenic mammary epithelial (MCF-12 A) cell lines using the resazurin assay.ResultsEight stigmasterol derivatives were successfully synthesized namely; Stigmasterol acetate (2), Stigmasta-5,22-dien-3,7-dione (3), 5,6-Epoxystigmast-22-en-3β-ol (4), 5,6-Epoxystigmasta-3β,22,23-triol (5), Stigmastane-3β,5,6,22,23-pentol (6), Stigmasta-5-en-3,7-dion-22,23-diol (7), Stigmasta-3,7-dion-5,6,22,23-ol (8) and Stigmast-5-ene-3β,22,23-triol (9). This is the first report of Stigmasta-5-en-3,7-dion-22,23-diol (7) and Stigmasta-3,7-dion-5,6,22,23-ol (8). The synthesized stigmasterol analogues showed improved cytotoxic activity overall compared to the stigmasterol (1), which was not toxic to the three cell lines tested (EC50 ˃ 250 µM). In particular, 5,6-Epoxystigmast-22-en-3β-ol (4) and stigmast-5-ene-3β,22,23-triol (9) displayed improved cytotoxicity and selectivity against MCF-7 breast cancer cells (EC50 values of 21.92 and 22.94 µM, respectively), while stigmastane-3β,5,6,22,23-pentol (6) showed improved cytotoxic activity against the HCC70 cell line (EC50: 16.82 µM).ConclusionNatural products from Rhoicissus tridentata and their derivatives exhibit a wide range of pharmacological activities, including anticancer activity. The results obtained from this study indicate that molecular modification of stigmasterol functional groups can generate structural analogues with improved anticancer activity. Stigmasterol derivatives have potential as candidates for novel anticancer drugs.

Synthesis of metalla-dual-azulenes with fluoride ion recognition properties

Azulene-based conjugated systems are of great interests due to their unusual structures and photophysical properties. Incorporation of a transition metal into azulene skeleton presents an intriguing opportunity to combine the dπ-pπ and pπ-pπ conjugated properties. No such metallaazulene skeleton however has been reported to date. Here, we describe our development of an efficient [5 + 2] annulation reaction to rapid construction of a unique metal-containing [5-5-7] scaffold, termed metalla-dual-azulene (MDA), which includes a metallaazulene and a metal-free organic azulene intertwined by sharing the tropylium motif. The two azulene motifs in MDA exhibit distinct reactivities. The azulene motif readily undergoes nucleophilic addition, leading to N-, O- and S-substituted cycloheptanetrienyl species. Demetalation of the metallaazulene moiety occurs when it reacts with nBu4NF, which enables highly selective recognition of fluoride anion and a noticeable color change. The practical [5 + 2] annulation methodology, facile functional-group modification, high and selective fluoride detection make this new π-conjugated polycyclic system very suitable for potential applications in photoelectric and sensing materials.

Modulating Electronic Structure Engineering of Atomically Dispersed Cobalt Catalyst in Fenton-like Reaction for Efficient Degradation of Organic Pollutants.

Currently, the lack of model catalysts limits the understanding of the catalytic essence. Herein, we report the functional group modification of model single atom catalysts (SACs) with an accurately regulated electronic structure for accelerating the sluggish kinetics of the Fenton-like reaction. The amino-modified cobalt phthalocyanine anchored on graphene (CoPc/G-NH2) shows superior catalytic performance in the peroxymonosulfate (PMS) based Fenton-like reaction with Co mass-normalized pseudo-first-order reaction rate constants (kobs, 0.2935 min-1), which is increased by 4 and 163 times compared to those of CoPc/G (0.0737 min-1) and Co3O4/G (0.0018 min-1). Density functional theory (DFT) calculations demonstrate that the modification of the -NH2 group narrows the gap between the d-band center and the Fermi level of a single Co atom, which strengthens the charge transfer rate at the reaction interface and reduces the free energy barrier for the activation of PMS. Moreover, the scale-up experiment realizes 100% phenol removal at 7200-bed volumes during 240 h continuous operation without obvious decline in catalytic performance. This work provides in-depth insight into the catalytic mechanism of Fenton-like reactions and demonstrates the electronic engineering of SACs as an effective strategy for improving the Fenton-like activity to achieve the goal of practical application.

Interfacial superionic conductor towards solidified lithium-ion batteries with superb rate performance and long cycle life

The poor interface contact between the electrode and solid electrolyte is a major obstacle damaging the cycle performance and stability of solid-state lithium-ion batteries. Adding inorganic or organic layer as the buffers on the electrode/electrolyte interface can improve the physical contact, but still hardly achieve high rate capability due to the slow ion-diffusion kinetics on the interface. Here, we design an organic interfacial superionic conductor (ISC) with high ion-conductivity based on polyether polyols (PPG) through polar functional-group modification to enhance the ion-diffusion kinetics on the polyurethane-based electrolyte/cathode interface and construct ion-conductive framework in LFP cathode, which was verified by cryogenic electron microscopy (Cryo-EM) and surface enhanced Raman spectroscopy (SERS). Consequently, the assembled LFP cathode demonstrated a high specific capacity of ∼95.7 mAh/g with retention of ∼92% after 1000 cycles at 10 C.

Novel Strategy for Optimizing the Antibacterial Activity of Psidium guajava Against Clinical Isolates of Escherichia coli, Staphylococcus aureus, Salmonella spp., and Streptococcus spp.

The development of a new antibiotic is a challenging task, with an estimated failure rate of 95%. Minor changes in the chemical structure of a drug, such as stereochemistry, geometry, or functional group modifications, can significantly impact its medicinal activity. In this study, we aim to devise novel strategies for optimizing the antimicrobial properties of guava leaf extract through simple reactions, either by self-reaction or combination reactions with a reagent, drug, or different plant extract. Fourier transform infrared spectroscopy analysis revealed conjugation and formation of new functional groups in the prepared sample of Guava Guava (GG) and Guava Aspirin Guava (GAG), which were further confirmed by weight analysis. The results demonstrated that the antimicrobial activity of medicinal plants can be improved or optimized through simple reactions, such as combining the plant extract with a non-antimicrobial drug like aspirins or adding a small volume of concentrated sulfuric acid to the plant extract by heating at a temperature range of 100 – 110°C. Among the two combinatory methods used, GG exhibited better performance in inhibiting the growth of all tested bacterial strains at a concentration of 0.1 mg/mL compared to GAG at the same concentration, which inhibited the growth of only two bacterial strains: Escherichia coli and Streptococcus spp. These methods can be further explored and applied in various studies, including antifungal, anti-inflammatory, antiviral, and anticancer research, leveraging the availability and diverse range of natural products found in medicinal plants.