425 results
Search Results
2. Photo‐Controllable Ultralong Room‐Temperature Phosphorescence: State of the Art.
- Author
-
Nie, Fei and Yan, Dongpeng
- Subjects
- *
PHOTOCHROMIC materials , *PHOSPHORESCENCE , *ELECTRONIC paper , *INORGANIC polymers , *DIARYLETHENE , *SMALL molecules , *OPTOELECTRONICS , *MOIETIES (Chemistry) - Abstract
In this concept, we showcase the upsurge in the studies of dynamic ultralong room‐temperature phosphorescence (RTP) materials containing inorganic and/or organic components as versatile photo‐responsive platforms. The goal is to provide a comprehensive analysis of photo‐controllable RTP, and meanwhile delve into the underlying RTP properties of various classes of photochromic materials including metal‐organic complexes, organic‐inorganic co‐crystals, purely organic small molecules and organic polymers. In particular, the design principles governing the integration of the photochromic and RTP moieties within a single material system, and the tuning of dynamic RTP in response to light are emphasized. As such, this concept sheds light on the challenges and opportunities of using these tunable RTP materials for potential applications in optoelectronics, particularly highlighting their use of reversible information encryption, erasable light printing and rewritable smart paper. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Building Polyoxometalate "Nano‐Walls" on 3D Porous Carbon Paper: A Solar Steam Generation System for Water Purification.
- Author
-
De, Qingcuomu and Xu, Xinxin
- Subjects
- *
CARBON paper , *WATER purification , *SALINE water conversion , *SOLAR thermal energy , *SOLAR energy conversion , *MARITIME shipping , *WATER efficiency - Abstract
As promising fresh‐water purification devices, solar steam generation systems have attracted significant attention recently. However, in practice, the approach often suffers from a poor solar energy conversion efficiency and a low water production rate due to poor material selection and inefficient microscopic structure design. Here, we fabricate an efficient solar steam generation system by "building" polyoxometalate "nano‐walls" on rice paper‐derived three‐dimensional porous carbon paper. In this solar steam generation system, the height of the vertically aligned CoP4Mo6 "nano‐walls" range from 100 to 150 nm with thicknesses about 15 to 25 nm. Under 1 sun irradiation (1 sun = 1 kW m−2), the surface temperature increases from 29 to 50 °C in a short time with a solar thermal conversion efficiency achieving 92.8 %. The stability and durability of this solar steam generation system, which withstands fifteen cycle continuous tests, also offer good prospects. Its attractive solar energy conversion performance originates from the intense sunlight absorption and high conversion ability of the CoP4Mo6 "nano‐walls", as well as extremely promising heat localization and water transportation properties of the three‐dimensional porous carbon paper. This solar steam generation system, which has produced some inspiring results, is employed for seawater desalination and for purification of water polluted with organic dyes. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
4. Luminescent Organic‐Inorganic Hybrid Metal Halides: An Emerging Class of Stimuli‐Responsive Materials.
- Author
-
Wang, Zeping and Huang, Xiaoying
- Subjects
- *
METAL halides , *ELECTRONIC paper , *ORGANIC conductors , *ORGANOMETALLIC compounds - Abstract
Luminescent organic‐inorganic metal halides (OIMHs) are well known as a new materials family in recent years. Novel materials and applications of luminescent OIMHs have been explored by changing either the organic component or the metal halide species. Thereinto, the stimuli‐responsive (SR) phenomena in OIMHs have drawn much attention recently, for not only their attractive application potential but also the helpfulness in understanding the stability of OIMHs to the external environment. Herein, the luminescent OIMHs that are sensitive to external stimuli including contact, pressure, mechanical grinding, light, heat, and gas molecules, are reviewed, with an emphasis on analyses of the structural change during the SR process. The applications of SR luminescent OIMHs in widespread fields, including gas sensing, information encryption, and rewritable luminescent paper are summarized. Finally, the challenges that deserve to be further explored in this research field are discussed, which provides certain guidance for the future study of SR luminescent OIMHs. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
5. Enhanced Energy Density of Coaxial Fiber Asymmetric Supercapacitor Based on MoS2@Fe2O3/Carbon Nanotube Paper and Ni(OH)2@NiCo2O4/Carbon Nanotube Fiber Electrodes.
- Author
-
He, Hang, Yang, Xijia, Wang, Liying, Zhang, Xueyu, Li, Xuesong, and Lü, Wei
- Subjects
- *
SUPERCAPACITOR electrodes , *ENERGY density , *ENERGY storage equipment , *ENERGY storage , *FIBERS , *POWER density - Abstract
Fiber supercapacitors are promising energy storage devices for potential application in wearable and miniaturized portable electronics, which currently suffer from difficulties in achieving high capacitance and energy density synchronously owing to the limited specific surface area of the electrode materials and material incompatibility between the two electrodes. Herein, a strategy is developed for the manufacture of coaxial asymmetric fiber supercapacitors by wrapping a core of PVA‐KOH gel electrolyte‐coated Ni(OH)2@NiCo2O4/CNT fibers with MoS2@Fe2O3/CNT paper. The as‐prepared coaxial fiber asymmetric supercapacitors exhibit a specific capacitance of 373 mF cm−2 (at a current density of 2 mA cm−2) and energy density of 0.13 mW h cm−2 (at a power density of 3.2 mW cm−2), and also show good rate capability, long cycle life, and excellent flexibility. This work provides the possibility for the practical application of fiber supercapacitors in wearable and portable energy storage equipment. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
6. Light‐Controlled Chemoenzymatic Immobilization of Proteins towards Engineering of Bioactive Papers.
- Author
-
Hilberg, Valentina, Avrutina, Olga, Ebenig, Aileen, Yanakieva, Desislava, Meckel, Tobias, Biesalski, Markus, and Kolmar, Harald
- Subjects
- *
RING formation (Chemistry) , *ENCAPSULATION (Catalysis) , *PERICYCLIC reactions , *CHEMICAL reactions , *SORTASES - Abstract
Efficient and reliable methods for the generation of bioactive papers are of growing interest in relation to point‐of‐care testing devices that do not require extensive analytical equipment. Herein, we report the immobilization of functional proteins on paper fibers using a modular chemoenzymatic approach. The synthetic strategy relies on a combination of highly efficient spatially controllable photo‐triggered cycloaddition followed by site‐specific sortase A‐catalyzed transamidation. This site‐directed and regiospecific method has allowed unidirectional and covalent immobilization of several proteins displaying different functional properties, with ramifications for application in paper‐based diagnostics. Protein‐functionalized paper: A modular approach to covalent protein immobilization on paper fibers is reported, which relies on a set of highly efficient pericyclic reactions in combination with site‐specific enzymatic coupling. Following initial derivatization of a cellulosic surface (see figure), light‐triggered covalent anchoring of an enzyme recognition site ensures enzyme‐promoted ligation of desired proteins with preservation of their function. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
7. Quantifying Biomolecular Binding Constants using Video Paper Analytical Devices.
- Author
-
Miller, Benjamin S., Parolo, Claudio, Turbé, Valérian, Keane, Candice E., Gray, Eleanor R., and McKendry, Rachel A.
- Subjects
- *
BIOMOLECULES , *MICROFLUIDICS , *IMMUNOGLOBULINS , *ANTIGEN analysis , *LANGMUIR isotherms - Abstract
Abstract: A novel ultra‐low‐cost biochemical analysis platform to quantify protein dissociation binding constants and kinetics using paper microfluidics is reported. This approach marries video imaging with one of humankind's oldest materials: paper, requiring no large, expensive laboratory equipment, complex microfluidics or external power. Temporal measurements of nanoparticle–antibody conjugates binding on paper is found to follow the Langmuir Adsorption Model. This is exploited to measure a series of antibody–antigen dissociation constants on paper, showing excellent agreement with a gold‐standard benchtop interferometer. The concept is demonstrated with a camera and low‐end smartphone, 500‐fold cheaper than the reference method, and can be multiplexed to measure ten reactions in parallel. These findings will help to widen access to quantitative analytical biochemistry, for diverse applications spanning disease diagnostics, drug discovery, and environmental analysis in resource‐limited settings. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
8. The Utilization of Metal‐Organic Frameworks and Their Derivatives Composite in Supercapacitor Electrodes.
- Author
-
Liu, Qianwen, Li, Ruidong, Li, Jie, Zheng, Bingyue, Song, Shuxin, Chen, Lihua, Li, Tingxi, and Ma, Yong
- Subjects
- *
METAL-organic frameworks , *CARBON-based materials , *CONDUCTING polymers , *POWER density , *ENERGY industries , *SUPERCAPACITORS , *SUPERCAPACITOR electrodes - Abstract
Up to now, the mainstream adoption of renewable energy has brought about substantial transformations in the electricity and energy sector. This shift has garnered considerable attention within the scientific community. Supercapacitors, known for their exceptional performance metrics like good charge/discharge capability, strong power density, as well as extended cycle longevity, have gained widespread traction across various sectors, including transportation and aviation. Metal‐organic frameworks (MOFs) with unique traits including adaptable structure, highly customizable synthetic methods, and high specific surface area, have emerged as strong candidates for electrode materials. For enhancing the performance, MOFs are commonly compounded with other conducting materials to increase capacitance. This paper provides a detailed analysis of various common preparation strategies and characteristics of MOFs. It summarizes the recent application of MOFs and their derivatives as supercapacitor electrodes alongside other carbon materials, metal compounds, and conductive polymers. Additionally, the challenges encountered by MOFs in the realm of supercapacitor applications are thoroughly discussed. Compared to previous reviews, the content of this paper is more comprehensive, offering readers a deeper understanding of the diverse applications of MOFs. Furthermore, it provides valuable suggestions and guidance for future progress and development in the field of MOFs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Fenton‐Like Reaction: Recent Advances and New Trends.
- Author
-
Xiao, Jiaying, Guo, Sufang, Wang, Dong, and An, Qi
- Subjects
- *
HABER-Weiss reaction , *HYDROGEN peroxide , *SOIL degradation , *IRON ions , *OIL spills , *SOIL pollution - Abstract
The Fenton reaction refers to the reaction in which ferrous ions (Fe2+) produce hydroxyl radicals and other reactive oxidizing substances by decomposing hydrogen peroxide (H2O2). This paper reviews the mechanism, application system, and materials employed in the Fenton reaction including conventional homogeneous and non‐homogeneous Fenton reactions as well as photo‐, electrically‐, ultrasonically‐, and piezoelectrically‐triggered Fenton reactions, and summarizes the applications in the degradation of soil oil pollutions, landfill leachate, textile wastewater, and antibiotics from a practical point of view. The mineralization paths of typical pollutant are elucidated with relevant case studies. The paper concludes with a summary and outlook of the further development of Fenton‐like reactions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Improving Fatigue Resistance and Autonomous Switching of pH Responsive Hydrazones by Pulses of a Chemical Fuel.
- Author
-
Maity, Pankaj, Pradhan, Harekrushna, Das, Asesh, Dalapati, Monotosh, and Samanta, Dipak
- Abstract
The chemically triggered reversible switching of pH‐responsive hydrazones involves rotary motion‐induced configurational changes, serving as a prototype for constructing an array of molecular machines. Typically, the configurational isomerization of such switches into two distinct forms (
E /Z ) occurs through the alteration of the pH the medium, achieved by successive additions of acid and base stimuli. However, this process results in intermittent operation due to the concomitant accumulation of salt after each cycle, limiting switching performance to only a few cycles (5–6). In this context, we introduce a novel strategy for the autonomousE /Z isomerization of hydrazones in acetonitrile using pulses of trichloroacetic acid as a chemical fuel. The use of this transient acid enabled reversible switching of hydrazones even after 50 cycles without causing significant fatigue. To test the broad viability of the fuel, a series ofortho /para‐ substituted hydrazones were synthesized and their switching performance was investigated. The analysis of kinetic data showed a strong dependency of switching operations including the lifetime of transient state, on the electronic properties of substituents. Finally, a distinct color change from yellow to orange due to reversible switching of thepara ‐methoxy substituted hydrazone was employed for the creation of rewritable messages on commercially available paper. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
11. One-Step Synthesis of Silver Nanoparticle-Decorated Hydroxyapatite Nanowires for the Construction of Highly Flexible Free-Standing Paper with High Antibacterial Activity.
- Author
-
Xiong, Zhi-Chao, Zhu, Ying-Jie, Chen, Fei-Fei, Sun, Tuan-Wei, and Shen, Yue-Qin
- Subjects
- *
ANTIBACTERIAL agents , *NANOWIRES , *SILVER ions , *BIOCOMPATIBILITY , *BIOMATERIALS - Abstract
A highly flexible and free-standing paper with high antibacterial activity made from silver nanoparticle (AgNP)-decorated ultralong hydroxyapatite nanowires (HAPNWs) is reported. The HAPNWs@AgNPs nanocomposites were obtained from a facile one-step solvothermal process and utilized for the construction of highly flexible and free-standing inorganic paper through a simple vacuum-filtration procedure. The structure and properties of the HAPNWs@AgNPs paper were characterized in detail. Scanning electron microscope (SEM) and transmission electron microscope (TEM) micrographs show that AgNPs are highly dispersed and stabilized in the nanocomposite and exhibit a narrow particle size distribution. The effects of the concentration of silver nitrate, solvothermal temperature and time on the product were systematically investigated. This method is simple, convenient and reproducible. The as-prepared HAPNWs@AgNPs paper shows long-time sustained silver-ion release, high antibacterial activity against both Gram-negative and Gram-positive bacteria, and good biocompatibility. Overall, this work provides a novel pathway for the preparation of a new type of highly flexible, free-standing and antibacterial inorganic paper made from silver nanoparticle-decorated hydroxyapatite nanowires for various applications, as a promising functional biomaterial. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
12. Degradation Products from Naturally Aged Paper Leaves of a 16th-Century-Printed Book: A Spectrochemical Study.
- Author
-
Bronzato, Maddalena, Calvini, Paolo, Federici, Carlo, Bogialli, Sara, Favaro, Gabriella, Meneghetti, Moreno, Mba, Miriam, Brustolon, Marina, and Zoleo, Alfonso
- Subjects
- *
SPECTRUM analysis , *BOOK deacidification , *PAPER deterioration , *NUCLEAR magnetic resonance , *ELECTRON paramagnetic resonance , *X-ray fluorescence , *INDUCTIVELY coupled plasma spectrometry , *HIGH performance liquid chromatography - Abstract
In this work, we present a wide-range spectrochemical analysis of the degradation products from naturally aged paper. The samples obtained from wash waters used during the de-acidification treatment of leaves from a 16th-century-printed book were analysed through NMR, IR, Raman UV/Vis, EPR and X-ray fluorescence (XRF) spectroscopy and HPLC-MS and inductively coupled plasma (ICP) analysis. By these methods we also studied some of the previous samples treated by acidification (sample AP) and catalytic hydrogenation (sample HP). Crossing all the data, we obtained precise indications about the main functional groups occurring on the degraded, water-soluble cellulose oligomers. These results point out that the chromophores responsible for browning are conjugated carbonyl and carboxyl compounds. As a whole, we show that the analysis of wash waters, used in the usual conservation treatments of paper de-acidification, gives much valuable information about both the conservation state of the book and the degradation reactions occurring on the leaves, due to the huge amount of cellulose by-products contained in the samples. We propose therefore this procedure as a new very convenient general method to obtain precious and normally unavailable information on the cellulose degradation by-products from naturally aged paper. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
13. Unravelling the Role of Free Radicals in Photocatalysis.
- Author
-
Chen, Yao, Xu, Shuyang, Fang Wen, Chun, Zhang, Hanyun, Zhang, Ting, Lv, Fujian, Yue, Yinghong, and Bian, Zhenfeng
- Subjects
- *
FREE radicals , *RADICALS (Chemistry) , *CHEMICAL reactions , *ORGANIC compounds , *PRECIOUS metals , *PHOTOCATALYSIS - Abstract
Free radicals are increasingly recognized as active intermediate reactive species that can participate in various redox processes, significantly influencing the mechanistic pathways of reactions. Numerous researchers have investigated the generation of one or more distinct photogenerated radicals, proposing various hypotheses to explain the reaction mechanisms. Notably, recent research has demonstrated the emergence of photogenerated radicals in innovative processes, including organic chemical reactions and the photocatalytic dissolution of precious metals. To harness the potential of these free radicals more effectively, it is imperative to consolidate and analyze the processes and action modes of these photogenerated radicals. This conceptual paper delves into the latest advancements in understanding the mechanics of photogenerated radicals. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
14. [Gd(HB‐DO3A)]: Equilibrium, Dissociation Kinetic and Structural Differences in a Simple Homolog of [Gd(HP‐DO3A)] (Prohance®).
- Author
-
Versolatto, Silvia, Boccalon, Mariangela, Guidolin, Nicol, Travagin, Fabio, Alessio, Enzo, Aime, Silvio, Balducci, Gabriele, Giovenzana, Giovanni B., and Baranyai, Zsolt
- Subjects
- *
CONTRAST media , *GADOLINIUM , *LIGANDS (Chemistry) , *EQUILIBRIUM , *MAGNETIC resonance imaging - Abstract
[Gd(HP‐DO3A)] (gadoteridol) as an active compound of ProHance® is a widely employed contrast agent in clinical MRI scans in the last 30 years. Recent concerns about the long‐term retention of gadolinium‐based contrast agents (GBCAs) led to a deeper investigation of the structural features underlying the integrity of the paramagnetic metal complex. Several human and nonclinical studies have noted marked differences among the macrocyclic GBCAs, with the least retention of Gd traces and most rapid elimination consistently being reported for [Gd(HP‐DO3A)]. It was deemed of interest to assess how minor structural/electronic changes associated to the ligand structure may affect basic properties of the metal complex with several [Gd(HP‐DO3A)] analogues synthesized and characterized in the last years. We recently reported that the closest homolog of [Gd(HP‐DO3A)], i. e.: [Gd(HB‐DO3A)], in which a (±)‐2‐hydroxy‐1‐propyl pendant arm is replaced by a (±)‐2‐hydroxy‐1‐butyl moiety, showed a significantly different retention behaviour in the model interaction with collagen, despite the apparently very minor structural difference. In this paper we report a comprehensive study of the structural, thermodynamic, kinetic and relaxation properties of [Gd(HB‐DO3A)], compared to the parent [Gd(HP‐DO3A)] and to other closely related macrocyclic GBCAs to assess whether very minor structural changes can modulate the physico‐chemical properties of Gd3+ complexes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
15. Suppressing Cis/Trans 'Ring‐Flipping' in Organoaluminium(III)‐2‐Pyridyl Dimers–Design Strategies Towards Lewis Acid Catalysts for Alkene Oligomerisation.
- Author
-
Choudhury, Dipanjana, Lam, Ching Ching, Farag, Nadia L., Slaughter, Jonathan, Bond, Andrew D., Goodman, Jonathan M., and Wright, Dominic S.
- Subjects
- *
ACID catalysts , *LEWIS acids , *ALKENES , *OXIDATION states , *DEMETHYLATION , *LEWIS acidity - Abstract
Owing to its high natural abundance compared to the commonly used transition (precious) metals, as well as its high Lewis acidity and ability to change oxidation state, aluminium has recently been explored as the basis for a range of single‐site catalysts. This paper aims to establish the ground rules for the development of a new type of cationic alkene oligomerisation catalyst containing two Al(III) ions, with the potential to act co‐operatively in stereoselective assembly. Five new dimers of the type [R2Al(2‐py′)]2 (R=Me, iBu; py′=substituted pyridyl group) with different substituents on the Al atoms and pyridyl rings have been synthesised. The formation of the undesired cis isomers can be suppressed by the presence of substituents on the 6‐position of the pyridyl ring due to steric congestion, with DFT calculations showing that the selection of the trans isomer is thermodynamically controlled. Calculations show that demethylation of the dimers [Me2Al(2‐py′)]2 with Ph3C+ to the cations [{MeAl(2‐py')}2(μ‐Me)]+ is highly favourable and that the desired trans disposition of the 2‐pyridyl ring units is influenced by steric effects. Preliminary experimental studies confirm that demethylation of [Me2Al(6‐MeO‐2‐py)]2 can be achieved using [Ph3C][B(C6F5)4]. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
16. Crystalline CdS/Amorphous Cd(OH)2 Composite for Electrochemical CO2 Reduction to CO in a Wide Potential Window.
- Author
-
Hua, Zhixin, Qi, Kongsheng, Mi, Yulan, Zhao, Yuhua, Wu, Xinjie, Guo, Weiwei, Wan, Xiaoqi, Fan, Zixi, and Yang, Dexin
- Abstract
Electrochemical CO2 reduction is a promising method for converting atmospheric CO2 into valuable low‐carbon chemicals. In this study, a crystalline cadmium sulfide/amorphous cadmium hydroxide composite was successfully deposited on the carbon paper substrate surface by in‐situ chemical bath deposition (named as c‐CdS/a‐Cd(OH)2/CP electrodes) for the efficient electrochemical CO2 reduction to produce CO. The c‐CdS/a‐Cd(OH)2/CP electrode exhibited high CO Faradaic efficiencies (>90 %) under a wide potential window of 1.0 V, with the highest value reaching ~100 % at the applied potential ranging from −2.16 V to −2.46 V vs. ferrocene/ferrocenium (Fc/Fc+), superior to the crystalline counterpart c‐CdS/CP and c‐CdS/c‐Cd(OH)2@CP electrodes. Meanwhile, the CO partial current density reached up to 154.7 mA cm−2 at −2.76 V vs. Fc/Fc+ on the c‐CdS/a‐Cd(OH)2/CP electrode. The excellent performance of this electrode was mainly ascribed to its special three‐dimensional structure and the introduction of a‐Cd(OH)2. These structures could provide more active sites, accelerate the charge transfer, and enhance adsorption of *COOH intermediates, thereby improving the CO selectivity. Moreover, the electrolytes consisting of 1‐butyl‐3‐methylimidazolium tetrafluoroborate and acetonitrile also enhanced the reaction kinetics of electrochemical CO2 reduction to CO. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
17. Recent Advancements in Continuous‐Flow Suzuki‐Miyaura Coupling Utilizing Immobilized Molecular Palladium Complexes.
- Author
-
Zhang, Zhenzhong and Yamada, Yoichi M. A.
- Subjects
- *
PALLADIUM compounds , *CATALYST structure , *CHEMICAL-looping combustion , *HETEROGENEOUS catalysis , *COUPLING reactions (Chemistry) , *CATALYSTS , *BATCH reactors - Abstract
Immobilized Pd‐catalyzed Suzuki‐Miyaura coupling under continuous‐flow conditions using a packed‐bed reactor, representing an efficient, automated, practical, and safe technology compared to conventional batch‐type reactions. The core objective of this study is the development of an active and durable catalyst. In contrast to supported Pd nanoparticles, the attachment of Pd complexes onto solid supports through well‐defined coordination sites is considered a favorable approach for preparing highly dispersed and stabilized Pd species. These species can be directly employed in various flow reactions without the need for pre‐treatment. This concept paper explores recent achievements involving the application of immobilized Pd complexes as precatalysts for continuous‐flow Suzuki‐Miyaura coupling. Our focus is to elucidate the significance of the designed catalyst structures in relation to their catalytic performance under flow conditions. Additionally, we highlight various reaction systems and catalyst packing methods, emphasizing their crucial roles in establishing a practical synthesis process. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. Tailoring the Properties of Gel Polymer Electrolytes for Sodium‐Ion Batteries Using Ionic Liquids: A Review.
- Author
-
Gabryelczyk, Agnieszka and Swiderska‐Mocek, Agnieszka
- Subjects
- *
POLYELECTROLYTES , *POLYMER colloids , *IONIC liquids , *SODIUM ions , *MELTING points , *IONIC conductivity , *IONIC structure , *ENERGY storage - Abstract
Ionic liquids are an extraordinary group of compounds, fully ionic in structure like inorganic salts but with low melting points, that resemble organic molecular solvents. Their chemical, electrochemical, and thermal stability is what draws the attention and enables their use in many applications, including electrochemical power sources. Even though they are no longer considered eco‐friendly because of nonnegligible toxicity and long bioaccumulation, they can still be efficiently recovered, purified, and reused. These attributes can be harvested to enhance the properties of gel polymer electrolytes for the emerging sodium‐ion batteries. The variety of anions and cations for ILs and their influence on the final properties of the compound opens the road to tuning the properties of gel polymer electrolytes. Ionic liquids as plasticizers constitute a major part of gel polymer electrolytes (average of 70 wt%) and hence, they affect the fundamental properties of gel electrolytes like ionic conductivity and electrochemical window. They also improve the safety features of sodium‐ion batteries, which is relevant for their anticipated applications in stationary energy storage and electric vehicles. The presented review paper aims to explain the relationship between the cation and anion in ionic liquid and the properties of gel electrolytes for sodium‐ion batteries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Emergent Properties in Chemistry ‐ Relating Molecular Properties to Bulk Behavior.
- Author
-
Sieroka, Norman, Lossau, Tammo, and Neudecker, Tim
- Subjects
- *
QUANTUM phase transitions , *CHEMICAL properties - Abstract
Certain properties of an object only emerge when a sufficient number of those objects are present in a definite arrangement. For example, one or two water molecules cannot said to be in a liquid state, but a drop of water can be. This concept of emergence has been studied extensively, but only occasionally discussed explicitly in the context of chemistry. In this paper, we aim to show the fruitfulness of the concept of emergence for chemical inquiry by considering four case studies of emergent chemical properties, i. e., the liquidity and freezing of water, structural properties of crystals, thermodynamical phase transitions and quantum mechanical phenomena. We show that some of these properties emerge gradually, some at discrete points, and some should be taken to emerge only when the number of constituents tends to infinity. We argue that studying the way in which chemical properties emerge presents a useful avenue for research that promises greater insight into the nature of those properties. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
20. Palladium‐Catalyzed Enantioselective [4+2] Cycloaddition of 4‐Vinylbenzodioxinones with Barbiturate‐Derived Alkenes: Con‐struction of Chiral Spirobarbiturate−Chromanes.
- Author
-
Tang, Yi, Huang, Mingxia, Ding, Siyuan, Liu, Xinyao, Huyang, Xiaochun, Wang, Bo, and Guo, Hongchao
- Subjects
- *
ALKENES , *RING formation (Chemistry) , *PALLADIUM , *CATALYSIS - Abstract
In this paper, Pd‐catalyzed [4+2] decarboxylative cycloaddition of 4‐vinylbenzodioxinones with barbiturate‐derived alkenes has been developed, leading to various spirobarbiturate−chromane derivatives in high yields with excellent diastereo‐ and enantioselectivities. The scale‐up reaction and further derivation of the product were demonstrated. A plausible reaction mechanism was also proposed. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
21. Recent Advances of Flexible MXene and its Composites for Supercapacitors.
- Author
-
Jiang, Shiben, Lu, Linghong, and Song, Yan
- Subjects
- *
ELECTRIC conductivity , *SURFACE chemistry - Abstract
MXenes have unique properties such as high electrical conductivity, excellent mechanical properties, rich surface chemistry, and convenient processability. These characteristics make them ideal for producing flexible materials with tunable microstructures. This paper reviews the laboratory research progress of flexible MXene and its composite materials for supercapacitors. And introduces the general synthesis method of MXene, as well as the preparation and properties of flexible MXene. By analyzing the current research status, the electrochemical reaction mechanism of MXene was explained from the perspectives of electrolyte and surface terminating groups. This review particularly emphasizes the composite methods of freestanding flexible MXene composite materials. The review points out that the biggest problem with flexible MXene electrodes is severe self‐stacking, which reduces the number of chemically active sites, weakens ion accessibility, and ultimately lowers electrochemical performance. Therefore, it is necessary to composite MXene with other electrode materials and design a good microstructure. This review affirms the enormous potential of flexible MXene and its composite materials in the field of supercapacitors. In addition, the challenges and possible improvements faced by MXene based materials in practical applications were also discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
22. Energy Barriers and Gap Between Two Excited States in a Dual‐Emissive Carborane.
- Author
-
Zhao, Xueyuan, Zhang, Xinning, Li, Xin, Wu, Lin, and Ji, Lei
- Abstract
A thorough understanding of the internal conversion process between excited states is important for the designing of ideal multiple‐emissive materials. However, it is hard to experimentally measure both the energy barriers and gaps between the excited states of a compound. For a long time, it is dubious if what was measured is the energy gap or barrier between two excited states. In this paper, we designed 1‐(pyren‐2’‐yl)‐9,12‐
di (p ‐tolyl)‐o ‐carborane (2 ), which shows dual‐emission in solution. Temperature‐dependent fluorescence measurements show that the two emission bands in hexane are corresponding to two different excited states. The ratio of the emission bands is controlled by thermodynamics at higher temperatures and by kinetics at lower temperatures. Thus, the energy barrier and energy gaps between the two excited states of2 can be experimentally estimated. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
23. Bi(III) Binding Stoichiometry and Domain-Specificity Differences Between Apo and Zn(II)-bound Human Metallothionein 1a.
- Author
-
Korkola, Natalie C., Ostertag, Anne-Lena, Toswell, Emily, and Stillman, Martin J.
- Subjects
- *
METALLOTHIONEIN , *BISMUTH , *DOMAIN specificity , *STOICHIOMETRY , *COPPER , *ELECTROSPRAY ionization mass spectrometry , *BINDING constant - Abstract
Bismuth is a xenobiotic metal with a high affinity to sulfur that is used in a variety of therapeutic applications. Bi(III) induces the cysteine-rich metallothionein (MT), a protein known to form two-domain cluster structures with certain metals such as Zn(II), Cd(II), or Cu(I). The binding of Bi(III) to MTs has been previously studied, but there are conflicting reports on the stoichiometry and binding pathway, which appear to be highly dependent on pH and initial metal-loading status of the MT. Additionally, domain specificity has not been thoroughly investigated. In this paper, ESI-MS was used to determine the binding constants of [Bi(EDTA)]-binding to apo-MT1a and its individual aMT fragment. The results were compared to previous experiments using ßMT1a and βαMT3. Domain specificity was investigated using proteolysis methods and the initial cooperatively formed Bi2MT was found to bind to cysteines that spanned across the traditional metal binding domain regions. Titrations of [Bi-(EDTA)]-into Zn7MT were performed and were found to result in a maximum stoichiometry of Bi7MT, contrasting the Bi6MT formed when [Bi(EDTA)] was added to apo-MT. These results show that the initial structure of the apo-MT determines the stoichiometry of new incoming metals and explains the previously observed differences in stoichiometry. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. Synthesis Strategies, Preparation Methods, and Applications of Chiral Metal‐Organic Frameworks.
- Author
-
Zhang, Hui, Cheng, Qingsong, Pei, Hebing, He, Simin, Guo, Ruibin, Liu, Nijuan, and Mo, Zunli
- Abstract
Chiral Metal‐Organic Frameworks (CMOFs) is a kind of material with great application value in recent years. Formed by the coordination of metal ions or metal clusters with organic ligands. It has ordered and adjustable pores, multi‐dimensional network structure, large specific surface area and excellent adsorption properties. This material structure combines the properties of metal‐organic frameworks (MOFs) with the chiral properties of chiral molecules. It has great advantages in catalysis, adsorption, separation and other fields. Therefore, it has a wide range of applications in chemistry, biology, medicine and materials science. In this paper, various synthesis strategies and preparation methods of chiral metal‐organic frameworks are reviewed from different perspectives, and the advantages of each method are analyzed. In addition, the applications of chiral metal‐organic framework materials in enantiomer recognition and separation, circular polarization luminescence and asymmetric catalysis are systematically summarized, and the corresponding mechanisms are discussed. Finally, the challenges and prospects of the development of chiral metal‐organic frame materials are analyzed in detail. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
25. Total Chemical Synthesis of Aggregation‐Prone Disulfide‐Rich Starfish Peptides.
- Author
-
Wu, Hongkang, Praveen, Praveen, Handley, Thomas N. G., Chandrashekar, Chaitra, Cummins, Scott F., Bathgate, Ross A. D., and Hossain, Mohammed Akhter
- Abstract
A relaxin‐like gonad‐stimulating peptide (RGP), Aso‐RGP, featuring six cysteine residues, was identified in the Crown‐of‐Thorns Starfish (COTS, Acanthaster cf.
solaris ) and initially produced through recombinant yeast expression. This method yielded a single‐chain peptide with an uncleaved C‐peptide (His Tag) and suboptimal purity. Our objective was to chemically synthesize Aso‐RGP in its mature form, comprising two chains (A and B) and three disulfide bridges, omitting the C‐peptide. Furthermore, we aimed to synthesize a newly identified relaxin‐like peptide, Aso‐RLP2, from COTS, which had not been previously synthesized. This paper reports the first total chemical synthesis of Aso‐RGP and Aso‐RLP2. Aso‐RGP synthesis proceeded without major issues, whereas the A‐chain of Aso‐RLP2, in its reduced and unfolded state with two free thiols, presented considerable challenges. These were initially marked by “messy” RP‐HPLC profiles, typically indicative of synthesis failure. Surprisingly, oxidizing the A‐chain significantly improved the RP‐HPLC profile, revealing the main issue was not synthesis failure but the peptide's aggregation tendency, which initially obscured analysis. This discovery highlights the critical need to account for aggregation in peptide synthesis and analysis. Ultimately, our efforts led to the successful synthesis of both peptides with purities exceeding 95 %. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
26. Synthesis of [1]Benzothieno[3,2‐b][1]benzothiophenes through Iodine‐Mediated Sulfur Insertion Reaction.
- Author
-
Ito, Kazuki, Nakamura, Kohei, and Yoshida, Kazuhiro
- Subjects
- *
ORGANIC field-effect transistors , *SULFUR , *THIOPHENES - Abstract
[1]Benzothieno[3,2‐b][1]benzothiophenes (BTBTs) are important molecules that have been extensively studied as high‐performance organic field‐effect transistors (OFETs). Therefore, it is important to develop a simple synthetic method for these molecules. In this paper, a synthetic method to obtain the BTBTs from 2‐arylbenzo[b]thiophenes and elemental sulfur, in which two C−S bonds are formed at once, is described. In this method, molecular iodine plays a very important role as an additive. The role of iodine is discussed in the presumed reaction pathways. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Engineered Nanomaterials for Tumor Immune Microenvironment Modulation in Cancer Immunotherapy.
- Author
-
Xing, Hao and Li, Xiaomin
- Abstract
Tumor immunotherapy, represented by immune checkpoint blocking and chimeric antigen receptor (CAR) T cell therapy, has achieved promising results in clinical applications. However, it faces challenges that hinder its further development, such as limited response rates and poor tumor permeability. The efficiency of tumor immunotherapy is also closely linked to the structure and function of the immune microenvironment where the tumor resides. Recently, nanoparticle‐based tumor immune microenvironment (TIME) modulation strategies have attracted a great deal of attention in cancer immunotherapy. This is primarily due to the distinctive physical characteristics of nanoparticles, which enable them to effectively infiltrate the TIME and selectively modulate its key constituents. This paper reviews recent advances in nanoparticle engineering to improve anti‐cancer immunotherapy. Emerging nanoparticle‐based approaches for modulating immune cells, tumor stroma, cytokines and immune checkpoints are discussed, aiming to overcome current challenges in the clinic. In addition, integrating immunotherapy with various treatment modalities such as chemotherapy and photodynamic therapy can be facilitated through the utilization of nanoparticles, thereby enhancing the efficacy of cancer treatment. The future challenges and opportunities of using nanomaterials to reeducate the suppressive immune microenvironment of tumors are also discussed, with the aim of anticipating further advancements in this growing field. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Versatile Polymerization‐Induced Emission Polymers from Barbier Polymerization of Cinnamic Esters with Tunable Emission.
- Author
-
Sun, Xiao‐Li, Chen, Yu‐Jiao, Cai, Hua‐Wen, Gu, Xi‐Yao, Li, De‐Shan, Wu, Liang‐Tao, and Wan, Wen‐Ming
- Subjects
- *
HYDROXYCINNAMIC acids , *ESTERS , *POLYMERIZATION , *POLYMERS , *CHEMICAL structure , *EXPLOSIVES - Abstract
Cinnamic ester is a common and abundant chemical substance, which can be extracted from natural plants. Compared with traditional esters, cinnamic ester contains α,β‐unsaturated carbonyl structure with multiple reactive sites, resulting in more abundant reactivities and chemical structures. Here, a versatile polymerization‐induced emission (PIE) is successfully demonstrated through Barbier polymerization of cinnamic ester. Attributed to its abundant reactivities of α,β‐unsaturated carbonyl structure, Barbier polymerization of cinnamic esters with different organodihalides gives polyalcohol and polyketone via 1,2‐addition and 1,4‐addition, respectively, which is also confirmed by small molecular model reactions. Meanwhile, these organodihalides dependant polyalcohol and polyketone exhibit different non‐traditional intrinsic luminescence (NTIL) from aggregation‐induced emission (AIE) type to aggregation‐caused quenching (ACQ) type, where novel PIE luminogens (PIEgens) are revealed. Further potential applications in explosive detection are carried out, where it achieves TNT detection sensitivity at ppm level in solution and ng level on the test paper. This work therefore expands the structure and functionality libraries of monomer, polymer and NTIL, which might cause inspirations to different fields including polymer chemistry, NTIL, AIE and PIE. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. Catalyst‐Free Synthesis of Thiosulfonates and 3‐Sulfenylindoles from Sodium Sulfinates in Water.
- Author
-
Li, Shaoke, Huang, Zijun, Wang, Xin, Yingxiong, Hui, Niu, Guohao, Chen, Ziyan, and Zhang, Zhenlei
- Abstract
This paper presents a green and efficient aqueous‐phase method for the synthesis of thiosulfonates, which has the benefits of no need for catalysts or redox reagents and a short reaction time, providing a method with great economic value for synthesizing thiosulfonates. Furthermore, 3‐Sulfenylindoles can be easily synthesized using this method, which expands the potential applications of this reaction. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. Plasma Technology for Advanced Electrochemical Energy Storage.
- Author
-
Liang, Xinqi, Liu, Ping, Qiu, Zhong, Shen, Shenghui, Cao, Feng, Zhang, Yongqi, Chen, Minghua, He, Xinping, Xia, Yang, Wang, Chen, Wan, Wangjun, Zhang, Jun, Huang, Hui, Gan, Yongping, Xia, Xinhui, and Zhang, Wenkui
- Subjects
- *
LITHIUM-air batteries , *ENERGY storage , *LITHIUM sulfur batteries , *CARBON offsetting , *RADICALS (Chemistry) , *LITHIUM-ion batteries - Abstract
"Carbon Peak and Carbon Neutrality" is an important strategic goal for the sustainable development of human society. Typically, a key means to achieve these goals is through electrochemical energy storage technologies and materials. In this context, the rational synthesis and modification of battery materials through new technologies play critical roles. Plasma technology, based on the principles of free radical chemistry, is considered a promising alternative for the construction of advanced battery materials due to its inherent advantages such as superior versatility, high reactivity, excellent conformal properties, low consumption and environmental friendliness. In this perspective paper, we discuss the working principle of plasma and its applied research on battery materials based on plasma conversion, deposition, etching, doping, etc. Furthermore, the new application directions of multiphase plasma associated with solid, liquid and gas sources are proposed and their application examples for batteries (e. g. lithium‐ion batteries, lithium‐sulfur batteries, zinc‐air batteries) are given. Finally, the current challenges and future development trends of plasma technology are briefly summarized to provide guidance for the next generation of energy technologies. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Instant Visual Detection of Picogram Levels of Trinitrotoluene by Using Luminescent Metal-Organic Framework Gel-Coated Filter Paper.
- Author
-
Lee, Ji Ha, Kang, Sunwoo, Lee, Jin Yong, Jaworski, Justyn, and Jung, Jong Hwa
- Subjects
- *
EXPLOSIVES detection , *TNT (Chemical) , *PHOSPHORS , *FILTER paper , *GROUNDWATER pollution , *COLLOIDS - Abstract
There is an ongoing need for explosive detection strategies to uncover threats to human security including illegal transport and terrorist activities. The widespread military use of the explosive trinitrotoluene (TNT) for landmines poses another particular threat to human health in the form of contamination of the surrounding environment and groundwater. The detection of explosives, particularly at low picogram levels, by using a molecular sensor is seen as an important challenge. Herein, we report on the use of a fluorescent metal-organic framework hydrogel that exhibits a higher detection capability for TNT in the gel state compared with that in the solution state. A portable sensor prepared from filter paper coated by the hydrogel was able to detect TNT at the picogram level with a detection limit of 1.82 ppt (parts per trillon). Our results present a simple and new means to provide selective detection of TNT on a surface or in aqueous solution, as afforded by the unique molecular packing through the metal-organic framework structure in the gel formation and the associated photophysical properties. Furthermore, the rheological properties of the MOF-based gel were similar to those of a typical hydrogel. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
32. Self-Powered and Sensitive DNA Detection in a Three-Dimensional Origami-Based Biofuel Cell Based on a Porous Pt-Paper Cathode.
- Author
-
Wang, Yanhu, Ge, Lei, Ma, Chao, Kong, Qingkun, Yan, Mei, Ge, Shenguang, and Yu, Jinghua
- Subjects
- *
BIOMASS energy , *CATHODES , *ORIGAMI , *GOLD nanoparticles , *DNA analysis , *SUPERCAPACITORS , *AMPLIFICATION reactions , *DIGITAL multimeters - Abstract
In this work, a mediator-less and compartment-less glucose/air enzymatic biofuel cell (BFC) was introduced into microfluidic paper-based analytical devices (μ-PADs) with gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs)-modified paper electrode as the anodic and cathodic substrate, respectively, to implement self-powered, sensitive, low-cost and simple DNA detection. As a further development of the analytical equipment, an all-solid-state paper supercapacitor (PS) was designed and integrated into the BFC for current amplification, and a terminal digital multi-meter detector (DMM) was introduced for the current detection. A highly sensitive DNA sensor was fabricated by covalently immobilizing the capture DNA in the AuNPs-modified anode. The nanoporous gold conjugated with bienzymes, glucose oxidase and horseradish peroxidase, which were used as electrochemical labels. The electrons generated at the anode flow through an external circuit to the PtNPs-modified cathode that catalyzed the reduction of oxygen with the participation of protons. In addition, the generated current could be collected and stored by the PS. After that, the PS was automatically shorted under the control of a switch to output an instantaneously amplified current, which could be sensitively detected by the terminal DMM. At the optimal conditions, the paper-based analytical platform can detect DNA at the femtomole level. This approach also shows excellent specificity toward single nucleotide mismatches. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
33. Controlling Cyclic Dienamine Reactivity in Radical tert‐Alkylation for Molecular Diversity to Synthesize Multicyclic Compounds Possessing a Quaternary Carbon.
- Author
-
Kusano, Shinjiro and Nishikata, Takashi
- Subjects
- *
RADICALS (Chemistry) , *ORGANIC synthesis , *ALKYL compounds , *CARBON , *ALKYLATION , *ENAMINES - Abstract
Synthesis of diverse sterically congested molecules from a single important intermediate is one of the ideal synthetic strategies in organic synthesis. In this paper, we found that γ‐oxoalkyl substituted cyclohexenone derivatives (OAC) possessing a quaternary carbon are a useful key intermediate to derive both congested fused [5,6] rings and spirocycles. For this purpose, we have established an efficient synthetic method to obtain OAC by tertiary alkylation of β‐methylcyclohexenone derivatives using α‐bromocarbonyl compounds as a tertiary alkyl source. The key to the success of this reaction is controlling the reactivity of the dienamine intermediate. While there have been many reports on enamine reactions, dienamine reactions have not been well studied. Herein, we report controlling reactivity of dienamines and molecular diversification from OAC. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. One‐Step Photochemical Preparation of CdS/Poly(MMA‐co‐MAA) Composite with Enhanced Photocatalytic Activity.
- Author
-
Huang, Zhenxun, Ma, Qingrong, and Sun, Fengqiang
- Subjects
- *
PHOTOCATALYSTS , *METHYL methacrylate , *METHACRYLIC acid , *ENVIRONMENTAL chemistry , *PHOTODEGRADATION , *SILVER phosphates - Abstract
This paper presents a one‐step photochemical method for the preparation of CdS/Poly(MMA‐co‐MAA) composite photocatalyst, based on the concept of simultaneous photocatalytic polymerization of organic monomers during UV‐light induced formation of CdS. The preparation is carried out in an aqueous solution of Na2S2O3, CdSO4, methyl methacrylate (MMA) and methacrylic acid (MAA), under a UV lamp. The continuously formed CdS particles with photocatalytic activity act the role of initiator to directly initiate the copolymerization of MMA and MAA, resulting in the in situ formation of the composite and full contact of the CdS particles with the oxygen‐containing groups in the polymer. Taking the photocatalytic degradation of methylene blue as a case study, the composite exhibited significantly higher activity under simulated solar light compared to the pure CdS. By analysis on various data, the enhanced photocatalytic activity is attributed to the enhanced visible light absorption, and especially the high electron‐hole separation efficiency caused by the electrostatic interaction between photogenerated holes and carbonyl oxygen atoms with negatively charged features. Furthermore, the composite displays excellent sunlight activity and recyclability, suggesting its potential for practical applications. Such a one‐step construction strategy relying only on photo‐energy is green, low‐cost and promising in obtaining high‐performance semiconductor/polymer composite photocatalysts. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Charge‐Assisted Ionic Hydrogen‐Bonded Organic Frameworks: Designable and Stabilized Multifunctional Materials.
- Author
-
Chen, Xu‐Yong, Cao, Li‐Hui, Bai, Xiang‐Tian, and Cao, Xiao‐Jie
- Subjects
- *
IONIC structure , *GAS absorption & adsorption , *HYDROGEN as fuel , *CRYSTAL structure , *SEPARATION of gases - Abstract
Hydrogen‐bonded organic frameworks (HOFs) are a class of crystalline framework materials assembled by hydrogen bonds. HOFs have the advantages of high crystallinity, mild reaction conditions, good solution processability, and reproducibility. Coupled with the reversibility and flexibility of hydrogen bonds, HOFs can be assembled into a wide diversity of crystalline structures. Since the bonding energy of hydrogen bonds is lower than that of ligand and covalent bonds, the framework of HOFs is prone to collapse after desolventisation and the stability is not high, which limits the development and application of HOFs. In recent years, numerous stable and functional HOFs have been developed by π–π stacking, highly interpenetrated networks, charge‐assisted, ligand‐bond‐assisted, molecular weaving, and covalent cross‐linking. Charge‐assisted ionic HOFs introduce electrostatic attraction into HOFs to improve stability while enriching structural diversity and functionality. In this paper, we review the development, the principles of rational design and assembly of charge‐assisted ionic HOFs, and introduces the different building block construction modes of charge‐assisted ionic HOFs. Highlight the applications of charge‐assisted ionic HOFs in gas adsorption and separation, proton conduction, biological applications, etc., and prospects for the diverse design of charge‐assisted ionic HOFs structures and multifunctional applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Celebrating Maurizio Prato's Passion, Talent and Imagination.
- Author
-
Bianco, Alberto, Bonchio, Marcella, Bonifazi, Davide, Da Ros, Tatiana, Maggini, Michele, Mateo‐Alonso, Aurelio, and Tecilla, Paolo
- Subjects
- *
YLIDES , *NANOSCIENCE , *MATERIALS science , *PHOTOINDUCED electron transfer , *EDUCATORS , *ORGANIC reaction mechanisms , *CHLOROPLASTS , *ORGANIC chemistry - Abstract
This article introduces a special collection of papers dedicated to Maurizio Prato, a renowned scientist in the field of carbon nanostructures and molecular nanoscience. The collection showcases Prato's team's achievements in integrating complex frontier research with groundbreaking advancements in these fields. Prato's work focuses on designing and synthesizing carbon nanostructures for applications in regenerative medicine and solar energy research. The article highlights Prato's scientific journey, his contributions to sustainable materials, and his impact on shaping functional nano-interfaces through precision chemistry. The Prato lab has made significant contributions to nanotechnology, particularly in the area of functionalized carbon nanotubes (f-CNT). Their research has shown that f-CNT are more biocompatible and easily cleared from the body compared to nonfunctionalized CNT. The lab has applied this knowledge to develop solutions for challenging problems such as healing spinal cord injuries and using water as a solar fuel. Their work in regenerative medicine has shown promising results in repairing severe and irreversible nervous system lesions, while their research in energy conversion has explored the use of f-CNT for solar energy conversion. Maurizio Prato, the leader of the lab, has fostered an interdisciplinary and collaborative environment, encouraging his team to explore diverse research avenues and promoting intellectual freedom. His mentorship and open-mindedness have been instrumental in the lab's success. [Extracted from the article]
- Published
- 2024
- Full Text
- View/download PDF
37. Pd‐Catalysed Direct Arylation of Distyrylbenzene: Strong Dual‐state Fluorescence and Electrochromism.
- Author
-
Nipate, Atul B. and Rao, M. Rajeswara
- Subjects
- *
FLUORESCENCE yield , *ELECTROCHROMIC effect , *ARYLATION , *FLUORESCENCE , *ARYL group , *CARBAZOLE , *TRIPHENYLAMINE - Abstract
Distyrylbenzenes (DSBs) are well‐known for their strong multicolour fluorescence. Fluorescence tuning of DSB via further functionalization/arylation, on the other hand, is uncommon. This paper reports a Pd‐catalysed direct arylation approach for introducing different aryl groups onto fluorobenzene‐containing DSB moiety (7) in high yields (67–72 %). The versatile methodology allows the substitution of neutral [tolyl (1)], electron‐deficient [p‐formyl benzene (2), p‐acetyl benzene (3), p‐nitrobenzene (4)] and electron‐rich [carbazole (5), triphenylamine (6)] aryl groups. The electron‐deficient aryls render mono‐substitution, while the electron‐rich counterparts promote di‐substitution. The compounds (1–6) show blue, green, and yellow fluorescence in both the solution and solid states; the fluorescence quantum yields reach >98 % and the peak maxima span from 425 to 560 nm. The mono‐carbazole DSB (5) exhibit white light emission (WLM) in polar solvents (acetone, DMF, CH3CN, DMSO and NMP) with very high fluorescence quantum yields (φf) of 60–80 %. For WLM, such high efficiency (φf) is somewhat uncommon. Moreover, visible‐to‐NIR reversible electrochromism is demonstrated by the TPA‐integrated DSB (6). The colour of 6 changes from pristine light yellow to orange, and the absorption maxima shifts from 372 to 1500 nm when a positive potential of 1.0 V vs Ag/Ag+ is applied. Moreover, the system shows high colouration efficiency in the NIR region with fast switching speeds for colouration and decolouration as fast as 0.98 s and 1.05 s. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Nucleophilic Substitution at Phosphorus Centres – Old and Recent Studies and a Final Solution of Mechanistic and Related Stereochemical Problems.
- Author
-
Mikołajczyk, Marian
- Subjects
- *
NUCLEOPHILIC substitution reactions , *PHOSPHORUS compounds , *PHOSPHORUS , *CYCLIC compounds , *STEREOCHEMISTRY , *PHOSPHORUS in water , *SUBSTITUTION reactions - Abstract
Among many problems of a fundamental value in the heteroatom chemistry the mechanism and stereochemistry of the nucleophilic substitution reaction at the phosphorus and other heteroatom centres have attracted great attention of phosphorus chemists already in the middle of the last century. This review, which does not have a comprehensive character, summarizes the selected original contributions aimed at solution of the mechanism of SN2−P reaction and its relationship with stereochemistry. The breakthrough in these studies was the Westheimer's concept and his rules which is presented at the beginning of this article. Next, a series of papers is presented where the stereochemistry of the substitution at phosphorus was investigated in cyclic five‐, four‐ and six‐membered ring phosphorus compound. The majority of these reactions have been found to occur with retention of the P‐configuration. In the third part of this account, the selected examples of substitution reactions at phosphorus in acyclic compounds are discussed. As the results of all the investigations discussed did not allow to undoubtedly ascribe the mechanism (SN2 or A−E) to the investigated reactions, in the last part the SN‐P reactions are presented, the mechanism of which has been established by combination of the stereochemical and DFT‐studies. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. Dansylated Nitrile N‐Oxide as the Fluorescent Dye Clickable to Unsaturated Bonds without Catalyst.
- Author
-
Oku, Yuki, Nakajima, Noriyuki, Hamada, Masahiro, and Koyama, Yasuhito
- Subjects
- *
FLUORESCENT dyes , *THREE-dimensional printing , *NITRILE oxides , *FLUORESCENCE spectroscopy , *NITRILE derivatives , *POLYMER blends , *MOLECULAR spectra - Abstract
Fluorescent polymeric materials have been exploited in the fields of aesthetical purposes, biomedical engineering, and three‐dimensional printing applications. While the fluorescent materials are prepared by the polymerization of fluorescent monomer or the blending a fluorescent dye with common polymer, the covalent immobilization of fluorescent dye onto common polymers is not the practical technique. In this paper, dansylated nitrile N‐oxide (Dansyl‐NO) has been designed and synthesized to be a stable nitrile N‐oxide as the derivative of 2‐hydroxy‐1‐naphthaldehyde. While Dansyl‐NO shows good reactivity to an alkene and an alkyne to give fluorescent Dansyl‐Ene and Dansyl‐Yne, respectively, it hardly reacts to a nitrile. The results indicate that Dansyl‐NO serves as a fluorescent dye clickable to alkenes and alkynes. To know the effects of solvent on the fluorescent properties, the UV‐vis and fluorescence spectra of Dansyl‐Ene are measured in three solvents. Dansyl‐Ene shows fluorescent solvatochromism, which appears to be red‐shifted along with the increase in solvent polarity. Poly(styrene‐co‐butadiene) directly reacts with Dansyl‐NO to give fluorescent modified SB. The emission spectrum of modified SB is blue‐shifted compared with that of Dansyl‐Ene. The blue‐shift could be possibly attributed to the presence of less polar polymer skeleton around the dansyl moieties of modified SB. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. Covalent Organic Frameworks as Electrode Materials for Alkali Metal‐ion Batteries.
- Author
-
Cui, Shuzhen, Miao, Wenxing, Peng, Hui, Ma, Guofu, Lei, Ziqiang, Zhu, Lei, and Xu, Yuxi
- Subjects
- *
CARBON-based materials , *ALKALIES , *POROSITY , *ELECTRODES , *COVALENT bonds , *CONJUGATED polymers - Abstract
Covalent organic frameworks (COFs) are a class of porous crystalline polymeric materials constructed by linking organic small molecules through covalent bonds. COFs have the advantages of strong covalent bond network, adjustable pore structure, large specific surface area and excellent thermal stability, and have broad application prospects in various fields. Based on these advantages, rational COFs design strategies such as the introduction of active sites, construction of conjugated structures, and carbon material composite, etc. can effectively improve the conductivity and stability of the electrode materials in the field of batteries. This paper introduces the latest research results of high‐performance COFs electrode materials in alkali metal‐ion batteries (LIBs, SIBs, PIBs and LSBs) and other advanced batteries. The current challenges and future design directions of COFs‐based electrode are discussed. It provides useful insights for the design of novel COFs structures and the development of high‐performance alkali metal‐ion batteries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. "Bubble‐Diode" Breathable Electrodes for Fast Gas Transport.
- Author
-
He, Yi and Tan, Peng
- Abstract
Bubbles arising from wild gas evolution commonly exist in electrochemical systems, particularly in water electrolysis and rechargeable aqueous batteries (e. g. Zn‐air batteries). Substantial energy dissipation occurs due to the obstruction of active sites and ion‐conducting pathways by evolving bubbles. Efforts are made to elucidate effective strategies for fast gas transport, most of which focus on minimizing bubble size and facilitating their timely detachment through complex techniques such as constructing super‐hydrophilic nano‐structure electrodes, flowing electrolytes, and ultrasonic oscillation. Recently, an innovative, facile, and highly efficient method utilizing a breathable electrode design to promote gaseous molecules to the external environment emerges as a promising approach since it avoids remarkable bubble accumulation while remaining free of additional accessories. This paper highlights the origin and evolution of this promising design. Starting with introducing the basic concept of traditional breathable electrodes based on hydrophobic polymer networks and discussing the current progress made in underlying mechanisms, a detailed description of the advanced design inspired by a "bubble‐diode" concept with superior breathability follows. This Concept aims to contribute to a deep understanding of this technology and paves the way for further advancements in this renewable energy era. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
42. Temperature Control of the Self‐Assembly Process of 4‐Aminoquinoline Amphiphile: Selective Construction of Perforated Vesicles and Nanofibers, and Structural Restoration Capability.
- Author
-
Hisamatsu, Yosuke, Toriyama, Go, Yamamoto, Katsuhiro, Takase, Hiroshi, Higuchi, Tsunehiko, and Umezawa, Naoki
- Abstract
The construction of diverse and distinctive self‐assembled structures in water, based on the control of the self‐assembly processes of artificial small molecules, has received considerable attention in supramolecular chemistry. Cage‐like perforated vesicles are distinctive and interesting self‐assembled structures. However, the development of self‐assembling molecules that can easily form perforated vesicles remains challenging. This paper reports a lower critical solution temperature (LCST) behavior‐triggered self‐assembly property of a 4‐aminoquinoline (4‐AQ)‐based amphiphile with a tetra(ethylene glycol) chain, in HEPES buffer (pH 7.4). This property allows to form perforated vesicles after heating at 80 °C (> LCST). The self‐assembly process of the 4‐AQ amphiphile can be controlled by heating at 80 °C (> LCST) or 60 °C (< LCST). After cooling to room temperature, the selective construction of the perforated vesicles and nanofibers was achieved from the same 4‐AQ amphiphile. Furthermore, the perforated vesicles exhibited slow morphological transformation into intertwined‐like nanofibers but were easily restored by brief heating above the LCST. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Direct Lithium Extraction Using Intercalation Materials.
- Author
-
Wang, Jing and Koenig, Gary M.
- Subjects
- *
CHEMICAL processes , *SUSTAINABLE development , *ELECTRIC vehicles , *ELECTRIC vehicle batteries , *LITHIUM , *CHEMICAL purification - Abstract
Worldwide lithium demand has surged in recent years due to increased production of Li‐ion batteries for electric vehicles and stationary storage. Li supply and production will need to increase such that the transition towards increased electrification in the energy sector does not become cost prohibitive. Many countries have taken policy steps such as listing Li as a critical mineral. Current commercial Li mining is mostly from dedicated mine sources, including ores, clays, and brines. The conventional ways to extract Li+ from those resources are through chemical processing and includes steps of calcination, leaching, precipitation, and purification. The environmental and economic sustainability of conventional Li processing has recently received increased scrutiny. Routes such as direct Li+ extraction may provide advantages relative to conventional Li+ extraction technologies, and one possible route to direct Li+ extraction includes leveraging intercalation materials. Intercalation material processing has recently demonstrated high selectivity towards Li+ as opposed to other cations. Reviews and reports of direct Li+ extraction with intercalation materials are limited, even as this technology has started to show promise in smaller‐scale demonstrations. This paper will review selective Li+ extraction via intercalation materials, including both electrochemical and chemical methods to drive Li+ in and out, and efforts to characterize the Li+ insertion/deinsertion processes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. Elucidating the Electronic Nature of Rh‐based Paddlewheel Catalysts from 103Rh NMR Chemical Shifts: Insights from Quantum Mechanical Calculations.
- Author
-
Gui, Xin, Sorbelli, Diego, Caló, Fabio P., Leutzsch, Markus, Patzer, Michael, Fürstner, Alois, Bistoni, Giovanni, and Auer, Alexander A.
- Subjects
- *
RHODIUM catalysts , *NUCLEAR magnetic resonance spectroscopy , *CATALYST structure , *LIGANDS , *CATALYSTS , *ELECTRONIC structure - Abstract
The tremendous importance of dirhodium paddlewheel complexes for asymmetric catalysis is largely the result of an empirical optimization of the chiral ligand sphere about the bimetallic core. It was only recently that a H(C)Rh triple resonance 103Rh NMR experiment provided the long‐awaited opportunity to examine – with previously inconceivable accuracy – how variation of the ligands impacts on the electronic structure of such catalysts. The recorded effects are dramatic: formal replacement of only one out of eight O‐atoms surrounding the metal centers in a dirhodium tetracarboxylate by an N‐atom results in a shielding of the corresponding Rh‐site of no less than 1000 ppm. The current paper provides the theoretical framework that allows this and related experimental observations made with a set of 19 representative rhodium complexes to be interpreted. In line with symmetry considerations, it is shown that the shielding tensor responds only to the donor ability of the equatorial ligands along the perpendicular principal axis. Axial ligands, in contrast, have no direct effect on shielding but may come into play via the electronic cis ${cis}$ ‐effect that they exert onto the neighboring equatorial sites. On top of these fundamental interactions, charge redistribution within the core as well as the electronic trans ${trans}$ ‐effect of ligands of different donor strengths is reflected in the recorded 103Rh NMR shifts. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. Iron Porphyrin Allows Fast and Selective Electrocatalytic Conversion of CO2 to CO in a Flow Cell.
- Author
-
Torbensen, Kristian, Han, Cheng, Boudy, Benjamin, Wolff, Niklas, Bertail, Caroline, Braun, Waldemar, and Robert, Marc
- Subjects
- *
IRON porphyrins , *ELECTROLYTIC reduction , *CARBON paper , *CARBON-black , *BASE catalysts , *FISCHER-Tropsch process - Abstract
Molecular catalysts have been shown to have high selectivity for CO2 electrochemical reduction to CO, but with current densities significantly below those obtained with solid‐state materials. By depositing a simple Fe porphyrin mixed with carbon black onto a carbon paper support, it was possible to obtain a catalytic material that could be used in a flow cell for fast and selective conversion of CO2 to CO. At neutral pH (7.3) a current density as high as 83.7 mA cm−2 was obtained with a CO selectivity close to 98 %. In basic solution (pH 14), a current density of 27 mA cm−2 was maintained for 24 h with 99.7 % selectivity for CO at only 50 mV overpotential, leading to a record energy efficiency of 71 %. In addition, a current density for CO production as high as 152 mA cm−2 (>98 % selectivity) was obtained at a low overpotential of 470 mV, outperforming state‐of‐the‐art noble metal based catalysts. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
46. Thioxanthylium Cations: Highly Reversible Hydrochromic Mate‐rials with Tunable Color and Moisture Sensitivity.
- Author
-
Chua, Ming Hui, Soo, Xiang Yun Debbie, Goh, Wei Peng, Png, Zhuang Mao, Zhu, Qiang, and Xu, Jianwei
- Subjects
- *
MOISTURE , *CATIONS , *TRIFLUOROACETIC acid , *COLOR , *HUMIDITY - Abstract
Hydrochromic materials, which change color in response to moisture, are highly sought‐after due to some unique applications such as moisture detection, humidity monitoring, anti‐counterfeiting, and sweat‐pore mapping. We herein report a new thioxanthene‐9‐ols/thioxanthylium cations hydrochromic system. The hydrochromic thioxanthylium cations can be generated/regenerated by exposing a chemically stable thioxanthene‐9‐ol to trifluoroacetic acid (TFA). The intensely colored thioxanthylium cations can be chemically reverted to the colorless thioxanthene‐9‐ol. Interestingly, the conversion between thioxanthene‐9‐ol and its cation species was found to be highly reversible in most cases (up to 50 activation‐deactivation cycles). The color and moisture‐sensitivity of thioxanthylium cations were also validated to be tunable via functionalization of the thioxanthene core with different aliphatic and aromatic groups at its 9 or 2,7‐positions. Finally, paper probes were prepared using solution‐immersion and inkjet‐printing techniques to demonstrate the system's potential applications in humidity sensing and anti‐counterfeiting [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
47. A Novel C Doped MoS2/CoP/MoO2 Ternary Heterostructure Nanoflower for Hydrogen Evolution Reaction at Wide pH Range and Efficient Overall Water Splitting in Alkaline Media.
- Author
-
Wang, Yan, Gao, Shanshan, Jiang, Yu, Song, Xiaoming, Tang, Guofeng, and Zhang, Xiangbin
- Subjects
- *
HYDROGEN evolution reactions , *OXYGEN evolution reactions , *WATER electrolysis , *HYDROGEN production , *REDUCING agents - Abstract
The development of low‐cost and high‐efficiency bifunctional catalysts is still a challenge for hydrogen production through overall water splitting. This paper reports the in‐situ synthesis of C‐doped MoS2/CoP/MoO2 using bacterial cellulose (BC) as the reducing agent and the source of C and using BC (MoS2/Co1.2MoO4.2 ⋅ 1.2H2O/BC) as the template. Heterogeneous structure for hydrogen evolution reaction (HER) and alkaline water electrolysis in a wide pH range. Due to the large number of defect sites caused by C doping and the synergy between these three active components (MoS2, CoP and MoO2), the HER and oxygen evolution reaction (OER) activities of the catalyst have been greatly improved. Therefore, during HER, a small initial overpotential (27 mV) was achieved in 1.0 M KOH. In 0.5 M H2SO4, 0.1 M PBS and 1.0 M KOH, the current density reached 10 mA cm−2 at overpotentials of 123.4, 150, and 139 mV, respectively. For OER, an overpotential of 268 mV was required to achieve 10 mA cm−2. The alkaline two‐electrode device composed of C doped MoS2/CoP/MoO2 delivers 10 mA cm−2 at a low potential of 1.51 V and can be easily driven by a single AA battery. This work provides a new design strategy of C doped ternary heterostructures for electrocatalysis and related energy applications. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. A Greener Pathway to Enantiopurity: Mechanochemical Deracemization through Abrasive Grinding.
- Author
-
Lopes, Chrystal, Cartigny, Yohann, Brandel, Clément, Dupray, Valérie, Body, Carole, Shemchuk, Oleksii, and Leyssens, Tom
- Subjects
- *
DERACEMIZATION , *PLANT growth , *MANUFACTURING processes , *PACLOBUTRAZOL , *ABRASIVES , *MECHANICAL abrasion - Abstract
We report the first case of mechanochemical deracemization by using liquid‐assisted abrasive grinding. The target molecule is a precursor of Paclobutrazol, an important fungicide and plant growth inhibitor. Using mechanochemical deracemization, we are even able to transform a 10 % ee scalemic mixture of this latter in an enantioenriched product of 97 % ee in a couple of hours. This is substantially shorter compared to solution‐based deracemization methodologies. The present paper thus introduces an efficient and greener process to enantiopure material. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. DFT Mechanistic Investigation on Manganese Pincer Complex Catalysed Cross‐Coupling of Methanol with Benzyl Alcohol to Afford Methyl Benzoate.
- Author
-
Ali, Qaim, Li, Zhewei, Zhang, Lin, Luo, Chenguang, Pu, Min, and Lei, Ming
- Subjects
- *
BENZYL alcohol , *METHYL benzoate , *METHANOL , *FORMIC acid , *ACTIVATION energy , *MANGANESE , *DENSITY functional theory - Abstract
In this paper the density functional theory (DFT) method was employed to investigate the cross‐coupling of methanol with benzyl alcohol to afford methyl benzoate, catalysed by Mn‐PNN pincer complex. The whole reaction process mainly includes three stages: the dehydrogenation of benzyl alcohol to benzaldehyde, the coupling of benzaldehyde with methanol to hemiacetal and the dehydrogenation of hemiacetal to methyl benzoate. The calculated results indicated that two dehydrogenation processes are influenced by two competitive mechanisms of inner and outer spheres. Dehydrogenation of benzyl alcohol to benzaldehyde is the rate‐determining step of the whole reaction, with the energy barrier of 22.1 kcal/mol. In addition, the regeneration of catalyst is also extremely important. Compared with direct dehydrogenation, the dehydrogenation mode assisted by formic acid is more advantageous. This work might provide theoretical insights and shed light on the design of cheap transition‐metal catalysts for the dehydrogenation reaction. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
50. Metallic and Dimensional Optimization of Metal–Organic Frameworks for High‐Performance Lithium‐Sulfur Batteries.
- Author
-
Li, Xinyi, Zhang, Xuguang, Xu, Yifan, Wang, Yige, Huang, Yang, and Ma, Mengtao
- Subjects
- *
METAL-organic frameworks , *LITHIUM sulfur batteries , *POLYSULFIDES , *ENERGY storage , *ENERGY density - Abstract
Lithium‐sulfur batteries (LSBs) have been considered as one of the most promising energy storage systems owing to their high theoretical energy density and abundant sulfuric resources. However, their commercial application is limited by rapid capacity decline and low Coulombic efficiency. Metal–organic frameworks (MOFs) made of metallic nodes and organic ligands can suppress polysulfide shuttling and promote redox kinetics. In this paper, the effects of crystallographic dimensions and metallic categories on chemical performance of LSBs have been meticulously explored electrochemical performance. As a result, exposed Ni active sites in a lamellar Ni‐MOF was found to deliver a superior electrochemical performance. The as‐assembled LSBs with 2D‐Ni‐MOF/CNTs cathode deliver a much superior initial discharge capacity, (820 mAh g−1 at 0.5 C), and exhibit excellent cycling stability over 550 cycles than those analogues of 3D stereoscopic Ni‐MOF and 2D lamellar Co‐MOF. This work proposed a perspective in elevating LSBs performance through synergistic optimization of the MOFs dimensions and the metallic nuclei in the cathodes. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.