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1.
Small ; 20(1): e2305119, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37653595

RESUMO

Rampant dendrite growth, electrode passivation and severe corrosion originate from the uncontrolled ions migration behavior of Zn2+ , SO4 2- , and H+ , which are largely compromising the aqueous zinc ion batteries (AZIBs) performance. Exploring the ultimate strategy to eliminate all the Zn anode issues is challenging but urgent at present. Herein, a fluorinated separator interface (PVDF@GF) is constructed simply by grafting the polyvinylidene difluoride (PVDF) on the GF surface to realize high-performance AZIBs. Experimental and theoretical studies reveal that the strong interaction between C─F bonds in the PVDF and Zn2+ ions enables evenly redistributed Zn2+ ions concentration at the electrode interface and accelerates the Zn transportation kinetics, leading to homogeneous and fast Zn deposition. Furthermore, the electronegative separator interface can spontaneously repel the SO4 2- and anchor H+ ions to alleviate the passivation and corrosion. Accordingly, the Zn|Zn symmetric cell with PVDF@GF harvests a superior cycling stability of 500 h at 10 mAh cm-2 , and the Zn|VOX full cell delivers 76.8% capacity retention after 1000 cycles at 2 A g-1 . This work offers an all-round solution and provides new insights for the design of advanced separators with ionic sieve function toward stable and reversible Zn metal anode chemistry.

2.
Chemistry ; 30(10): e202303461, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38050714

RESUMO

With the increasing demand for low-cost and high-safety portable batteries, aqueous zinc-ion batteries (ZIBs) have been regarded as a potential alternative to the lithium-ion batteries, bringing about extensive research dedicated in the exploration of high-performance and highly reversible ZIBs. Although separators are generally considered as non-active components in conventional research on ZIBs, advanced separators designs seem to offer effective solutions to the majority of issues within ZIBs system. These issues encompass concerns related to the zinc anode, cathode, and electrolyte. Initially, we delve into the origins and implications of various inherent problems within the ZIBs system. Subsequently, we present the latest research advancements in addressing these challenges through separators engineering. This includes a comprehensive, detailed exploration of various strategies, coupled with instances of advanced characterizations to provide a more profound insight into the mechanisms that influence the separators. Finally, we undertake a multi-criteria evaluation, based on application standards for diverse substrate separators, while proposing guiding principles for the optimal design of separators in zinc batteries. This review aims to furnish valuable guidance for the future development of advanced separators, thereby nurturing progress in the field of ZIBs.

3.
J Org Chem ; 89(10): 7216-7224, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38693864

RESUMO

An organoselenium-catalyzed C2,3-diarylation of unprotected N-H indoles with electron-rich aromatics has been developed. This one-pot multicomponent tandem cross-dehydrogenation coupling reaction allows for the incorporation of two different aromatic groups to indoles. More importantly, this approach offers significant advantages, including a high atom and step economy, eliminating the need for prepreparation of the reaction substrates, streamlining the synthetic process and enhancing its practicality. Overall, this organoselenium-catalyzed C2,3-diarylation reaction presents an efficient and versatile strategy for the functionalization of indole derivatives.

4.
J Org Chem ; 89(14): 10272-10282, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38967436

RESUMO

The exploration of remote functionalization of indoles is impeded by the inherently dominant reactivity intrinsic to the pyrrole moiety. Herein, we delineate a novel strategy facilitated by Lewis acid mediation, enabling the remote C-H functionalization, which culminates in the synthesis of an array of selectively functionalized indole derivatives, encompassing 3-trifluoroacetyl and 5-benzoyl motifs, utilizing trifluoroacetic anhydride and various acyl chlorides. Notably, the protocol exhibits versatility, as epitomized by the extension of C5-acylation to alkylation and sulfonation reactions. This methodology is distinguished by its exemplary regio- and chemo-selectivity, extensive substrate scope, commendable tolerance to a diverse array of functional groups, and the employment of comparatively mild reaction conditions.

5.
J Org Chem ; 89(15): 10953-10964, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39016014

RESUMO

Regiodivergent transition-metal-catalyzed oxidative C5- and ortho-alkynylation of 2-arylthiazoles have been demonstrated. Namely, Pd(II)-catalysis selectively generated C5-alkynylated products from the reaction of 2-arylthiazoles and terminal alkynes. In contrast, Ru(II)-catalysis exclusively provided ortho-alkynylated products from the same substrates. This protocol features a wide substrate scope, good functional group tolerance, high atom-economy, and exclusive regioselectivity. The alkynylated products can be readily converted into highly valuable synthons, which hold potential for applications in the fields of medicinal chemistry and materials science.

6.
Chem Commun (Camb) ; 60(52): 6679-6682, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38860866

RESUMO

Two complementary regiodivergent C-H alkynylations of 2-arylthiazoles are reported. When RuII catalysis is employed, an aryl ortho-alkynylation process is favored. The alkynylated products are gained in good yields. With the use of PdII catalysis, a thiazole C5-alkynylation process is developed, allowing for the construction of C5-alkynylated products. This strategy not only expands the methods for the functionalization of 2-arylthiazoles, but also provides new opportunities for the rapid assembly of complex molecular structures, which may have great potential in organic synthesis, medicinal chemistry, and materials science.

7.
Sci Total Environ ; 927: 172258, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583618

RESUMO

Population outbreaks of the crown-of-thorns starfish (COTS) seriously threaten the sustainability of coral reef ecosystems. However, traditional ecological monitoring techniques cannot provide early warning before the outbreaks, thus preventing timely intervention. Therefore, there is an urgent need for a more accurate and faster technology to predict the outbreaks of COTS. In this work, we developed an electrochemical biosensor based on a programmed catalytic hairpin assembly (CHA) and hybridization chain reaction (HCR) cyclic amplification strategy for sensitive and selective detection of COTS environmental DNA (eDNA) in water bodies. This biosensor exhibited excellent electrochemical characteristics, including a low limit of detection (LOD = 18.4 fM), low limit of quantification (LOQ = 41.1 fM), and wide linear range (50 fM - 10 nM). The biosensing technology successfully allowed the detection of COTS eDNA in the aquarium environment, and the results also demonstrated a significant correlation between eDNA concentration and COTS number (r = 0.990; P < 0.001). The reliability and accuracy of the biosensor results have been further validated through comparison with digital droplet PCR (ddPCR). Moreover, the applicability and accuracy of the biosensor were reconfirmed in field tests at the COTS outbreak site in the South China Sea, which has shown potential application in dynamically monitoring the larvae before the COTS outbreak. Therefore, this efficient electrochemical biosensing technology offers a new solution for on-site monitoring and early warning of the COTS outbreak.


Assuntos
Técnicas Biossensoriais , DNA Ambiental , Monitoramento Ambiental , Estrelas-do-Mar , Técnicas Biossensoriais/métodos , Animais , Monitoramento Ambiental/métodos , Recifes de Corais , China
8.
Org Lett ; 26(36): 7672-7677, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39230956

RESUMO

A one-pot strategy for iron-catalyzed C2,3-H arylphosphorylation of electron-deficient quinoxalines with phosphines and aryl compounds is reported. The proposed method features the use of non-noble metal catalysts, the capacity of utilizing multiple aryl compounds as substrates, the simultaneous formation of C-P and C-C bonds in one pot, the simplicity of its operation, the mildness of the reaction conditions, and its compatibility with a wide range of substrates. Moreover, it offers a practical route for direct access to 2-aryl-3-phosphino N-heteroarenes, a class of potential cyclometalated C^N and N^P bidentate ligands that are difficult to prepare with existing C(sp2)-H functionalization methods.

9.
Environ Sci Pollut Res Int ; 30(25): 67758-67770, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37115443

RESUMO

Endocrine-disrupting compounds (EDCs) are increasingly polluting water, making it of practical value to develop novel desirable adsorbents for removing these pollutants from wastewater. Here, a simple cross-linking strategy combined with gentle chemical activation was demonstrated to prepare starch polyurethane-activated carbon (STPU-AC) for adsorbing BPA in water. The adsorbents were characterized by various techniques such as FTIR, XPS, Raman, BET, SEM, and zeta potential, and their adsorption properties were investigated comprehensively. Results show that STPU-AC possesses a large surface area (1862.55 m2·g-1) and an abundance of functional groups, which exhibited superior adsorption capacity for BPA (543.4 mg·g-1) and favorable regenerative abilities. The adsorption of BPA by STPU-AC follows a pseudo-second-order kinetic model and a Freundlich isotherm model. The effect of aqueous solution chemistry (pH and ionic strength) and the presence of other contaminants (phenol, heavy metals, and dyes) on BPA adsorption was also analyzed. Moreover, theoretical studies further demonstrate that hydroxyl oxygen and pyrrole nitrogen are the primary adsorption sites. We found that the efficient recovery of BPA was associated with pore filling, hydrogen-bonding interaction, hydrophobic effects, and π-π stacking. These findings demonstrate the promising practical application of STPU-AC and provide a basis for the rational design of starch-derived porous carbon.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Carvão Vegetal/química , Poliuretanos , Amido , Poluentes Químicos da Água/análise , Fenóis/química , Água , Compostos Benzidrílicos/química , Adsorção , Cinética , Concentração de Íons de Hidrogênio
10.
ACS Omega ; 7(11): 9951-9957, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35350307

RESUMO

Bioreduction of gold ions by the thiol-modified M13 bacteriophage (M13-SH) has been exploited as the potential alternative to conventional methods based on toxic chemicals, due to the gold affinity of the thiol groups, inherent gold reduction, and high specific surface area of the filamentous virus. Such efforts have been hindered by harsh conditions involving strong reducing agents and extreme pH that are harmful to the virus. Herein, a virus-friendly and greener method of bioreduction of AuCl4 - at neutral pH based on M13-SH is demonstrated. M13-SH was prepared by coupling the virus with N-succinimidyl S-acetylthioacetate, followed by deacylation in the presence of hydroxylamine·HCl to expose the thiol groups. The key finding is that without time-consuming purification, the mixture after deacylation consisting of M13-SH, residual hydroxylamine, and so forth can directly turn ionic gold species into gold, leading to macroscopic precipitated products with interconnected linear structures consisting of fused gold nanoparticles. Besides working as the virus-friendly reducing agent with a unique autocatalytic style, hydroxylamine diminishes disulfide bonding-induced intervirus bundling of M13-SH so as to maintain its efficient biosorption of ionic gold precursors. This work demonstrates a general and green strategy of bioreduction of gold via combination of the gold-affinity proteins or organisms and the unique autocatalytic reduction of hydroxylamine.

11.
Int J Biol Macromol ; 193(Pt A): 71-80, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34637817

RESUMO

Herein, a TEMPO-oxidized cellulose-grafted-polystyrene hypercrosslinked polymer (TOC-PS-HCP) was synthesized facilely by TEMPO oxidation, grafting copolymerization and post crosslinking route. Based on the structural characterization, it was confirmed that TOC-PS-HCP mainly consisted of polystyrene chain on cellulose and rigid crosslinked bridge. Additionally, the as-prepared TOC-PS-HCP displayed appropriate hydrophobicity (water contact angle = 102.44°) and high specific surface area (SBET = 601.20 m2·g--1), which could efficiently recover ethylbenzene and styrene from PO/SM wastewater. The adsorption experiment was conducted to study the recovery performance for ethylbenzene and styrene in the aqueous phase. The results showed that TOC-PS-HCP could recover ethylbenzene and styrene quickly by adsorption process, and maintain a stable recovery rate both in different aqueous conditions and recycle experiments. The adsorption experiment in the simulated wastewater solution showed that TOC-PS-HCP exhibited the greater affinity for ethylbenzene and styrene than other substrates. Furthermore, a possible mechanism for the efficient recovery of ethylbenzene and styrene was suggested on the basis of experimental and theoretical results, which may be associated with van der Waals force and π-π stacking.


Assuntos
Celulose/química , Óxidos N-Cíclicos/química , Polímeros/química , Águas Residuárias/química , Purificação da Água/métodos , Adsorção
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