Electrochemical water splitting for H2 production is limited by the sluggish anode oxygen evolution reaction (OER), thus using hydrazine oxidation reaction (HzOR) to replace OER has received great ...attention. Here we report the hierarchical porous nanosheet arrays with abundant Ni3N‐Co3N heterointerfaces on Ni foam with superior hydrogen evolution reaction (HER) and HzOR activity, realizing working potentials of −43 and −88 mV for 10 mA cm−2, respectively, and achieving an industry‐level 1000 mA cm−2 at 200 mV for HzOR. The two‐electrode overall hydrazine splitting (OHzS) electrolyzer requires the cell voltages of 0.071 and 0.76 V for 10 and 400 mA cm−2, respectively. The H2 production powered by a direct hydrazine fuel cell (DHzFC) and a commercial solar cell are investigated to inspire future practical applications. DFT calculations decipher that heterointerfaces simultaneously optimize the hydrogen adsorption free energy (ΔGH*) and promote the hydrazine dehydrogenation kinetics. This work provides a rationale for advanced bifunctional electrocatalysts, and propels the practical energy‐saving H2 generation techniques.
An efficient bifunctional electrocatalyst toward hydrazine‐assisted H2 production was designed by constructing the Ni3N‐Co3N heterointerfaces on Ni foam (Ni3N‐Co3N PNAs/NF). The catalyst can achieve energy‐saving hydrogen production in an overall hydrazine splitting (OHzS) unit, showing its potential for practical applications.
Replacing dipolar and aprotic solvents with environmentally benign media has emerged as a new facet of green chemistry. In this paper, a sulfone‐containing imidazolium‐based Brønsted acid ionic ...liquid was prepared and used as a recyclable acid catalyst. The ionic liquid catalyst enables the use of an industrially acceptable and environmentally benign solvent, butyl acetate, as the reaction medium. The ionic liquid/butyl acetate biphasic system was successfully utilized in many organic reactions, which generally relied heavily on dipolar and aprotic solvents.
Dipolar and aprotic solvents are often required in acid‐catalyzed reactions, however, many of them are listed in solvent selection guides as not‐recommended due to their toxicity or explosivity. A ...catalytically functionalized ionic liquid, namely a sulfone‐containing imidazolium‐based Brønsted acid ionic liquid, was synthesized. It alleviates the detrimental effect of classical dipolar aprotic solvents because this ionic liquid integrates the function of a dipolar aprotic solvent able to stabilize carbocation intermediates and the activating effect of a strong Brønsted acid on electrophiles. The use of this tailor‐made ionic liquid was exemplified in some transformation reactions of indoles, which proceeded with high yield and selectivity using a green and an industrially acceptable solvent, butyl acetate. The recyclability of the ionic liquid catalyst was also demonstrated.
Industrially acceptable: Dipolar and aprotic solvents are widely used in organic synthesis. These solvents are however generally toxic and hazardous. We created a new ionic liquid that allow the acid‐catalyzed reactions performed very well in green and an industrially acceptable solvent, butyl acetate. Indole transformations are model reactions to show the proof‐of‐the‐concept.
An efficient strategy for the synthesis of bicyclic and tricyclic (aza‐)arenes from a nucleophilic (aza‐)arene with an electrophilic side arm was developed. The (aza‐)arene precursor has both ...nucleophilic and electrophilic sites, which were fixed at a 1,4‐distance. The bicyclic and tricyclic (aza‐)arene products were constructed via 4+2 annulation by using scandium(III) triflate as a catalyst and enolizable ketones or aldehydes as the counterpart reagents. A variety of six‐membered carbocycles and heterocycles, such as indolizines, indoles, naphthalenes, carbazoles, and pyrido1,2‐αindoles, were successfully synthesized. Some one‐pot sequential reactions were also developed, in which the 1,4‐donor‐acceptor precursors can be synthesized via oxidation of alcohols or a proper condensation reaction.
In ant-aphid interactions, various aphid species offer honeydew to the ant partner and increase their density by ant attendance, whilst others never attend ant species, in which case ants tend to ...treat them as prey. In this regard, ants should have the ability to distinguish myrmecophile aphid species from non-mutualistic species, so that mutualistic aphids will be accepted as partners rather than prey. Although ant-aphid interactions are now the focus of chemical ecology studies, the role of the different chemical stimuli in determining mutualistic interactions has not been completely clarified. Therefore, we have investigated the cuticular hydrocarbon profile of four myrmecophiles aphid species using GC-MS. We also investigated the behavior of the worker-ants (Lasius niger L., Hymenoptera: Formicidae) to different chemical stimuli derived from aphids. We applied four treatments and found that the behavior of the ant workers varied depending on the source of the different treatments. In particular, the real aphid Aphis pomi and the sugar solution proved to be the most attractive to the ants, while the presence of pure extract of the individuals is enough to disturb the behavior of the ants. We provide evidence that the key stimuli of the tending behavior could be the CHC patterns of the aphids and the CHC profile of the aphids tends to be genus specific. This research will promote further investigations to test the behavior of ant workers towards other species of aphids and treatment combinations.
A straightforward access to tricyclic indoles bearing 3,4-fused seven-membered rings has been established by using 4-aminoindoles as 1,4-bisnucleophiles in three-component reactions. ...1H-Azepino4,3,2-cdindoles, 4,6-dihydro-1H-azepino4,3,2-cdindoles and 1,3,4,6-tetrahydro-5H-azepino4,3,2-cdindol-5-ones could thus be synthesized in one pot in moderate to good yields. Beyond opening access to 3,4-fused tricyclic indoles, the use of easily accessible 4-aminoindoles as C,N-1,4-bisnucleophiles also provides a new platform to be used in a diversity-oriented synthesis strategy, fully displaying its benefits of maximizing molecular complexity and reaction diversity.
•SEK research has been classified into horizontal, vertical, and mixed processes.•The majority of SEK research has focused on the horizontal approach.•Horizontal SEK research has been divided into 19 ...subsections.•Vertical SEK research has been divided into 11 subsections.•Mixed SEK research has been divided into 7 subsections.
Since the early 1990s, soil electrokinetic remediation (SEKR) has been exploited for removing organic, inorganic, and radioactive material from contaminated soil. However, the application of SEKR has been met with multiple obstacles; thus, trials have been introduced to overcome these limitations. The present study provides a comprehensive review of various modifications applied to SEKR process designs. We classified the SEKR designs in horizontal, vertical, and mixed (horizontal and vertical) types as per the movement of contaminants. SEKR is conducted via four mechanisms, namely electromigration, electroosmosis, diffusion, and electrophoresis, when a direct current electrical field is applied among two electrodes to achieve contaminant movement from one location to another. During SEKR operation, the removal rate can be adversely affected by factors such as the formation of a pH jumping zone, very high (low) pH around the cathode (anode), polarization, and reduced current efficiency with increase in time. Accordingly, in a previous research, the regular design of SEKR has been modified to address these and other limitations. Moreover, soil electrokinetic (SEK) has been used for other applications such as land restoration, geophysics, dewatering, and consolidation. This review primarily aims to provide a comprehensive summary of the major design modification made to SEK processes in the past 28 years, (1993–2020) to facilitate research on the major aspects of SEK. As per our extensive literature survey, most relevant studies focused on the horizontal SEK design. This study discusses relevant SEK studies in which process design modification is considered.
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Sodium and potassium ions energy storage systems with low cost and high energy/power densities have recently drawn increasing interest as promising candidates for grid-level applications, while the ...lack of suitable anode materials with fast ion diffusion kinetics highly hinders their development. Herein, we develop a nanoscale confined in situ oxidation polymerization process followed by a conventional carbonization treatment to generate phosphorus and nitrogen dual-doped hollow carbon spheres (PNHCS), which can realize superior sodium and potassium ion storage performance. Importantly, the density functional theory calculation and combined characterizations, e.g., in situ Raman spectroscopy and ex situ X-ray photoelectron spectroscopy, decipher that the P/N doping can enhance the electronic transfer dynamics and ion adsorption capability, which are responsible for enhanced electrochemical performance. Inspiringly, the practicability of the PNHCS anode is demonstrated by assembling the potassium ion hybrid capacitors (KIHCs), where the prominent energy density is 178.80 Wh kg–1 at a power density of 197.65 W kg–1, with excellent cycling stability, can be achieved. This work not only promotes the development of efficient anode material for sodium/potassium ion storage devices but also deciphers the embedded ion storage mechanism.
•SEKR intensification process has been divided to six categories.•During 2017–2020, SEKR studies focused on inorganic and organic contaminants remediation.•During 2017–2020, few SEKR studies have ...focused on solidification and soil improvement.•SEKR is a proven suitable approach for low permeable soil remediation.
This review is a follow-up to our previous review titled “comprehensive review of progress made in soil electrokinetic research during 1993–2020, Part I: process design modifications with brief summaries of main output”. In this review, we have summarized the material additives that are utilized for the enhancement of soil electrokinetic remediation (SEKR) efficiency within the last four years (2017–2020). This review has been divided into six subjects according to determined SEKR categories including removal of inorganic contaminants, removal of organic contaminants, SEKR enhancement using permeable reactive barrier (PRB), SEKR for solidification and soil improvement, SEKR enhancement using an oxidation process, and SEKR enhancement using bioremediation and phytoremediation. Various enhancement materials have been added to improve the primary endeavors of SEKR and the summaries of the output were included in this review. In the SEKR experiments in which inorganic and organic contaminants were removed, the process was evaluated based on the process driving mechanism, particularly electromigration and electro-osmosis. Once the performance of SEKR was inefficient, the SEKR processing was integrated with PRB, oxidation, and bioremediation for significant improvements in SEKR performance. Therefore, the primary aim of our review is to provide a comparison of material additives for the SEKR removal intensification process from 2017 to 2020 to provide a review of the past materials that improved the SEKR performances and to simplify future innovation. During 2017–2020, SEKR studies focused on inorganic and organic contaminants remediation, whereas, few SEKR studies have focused on solidification and soil improvement. The SEKR has been utilized for dewatering, but in this case, the materials added were limited. The insufficient of relevant information on this subject was our primary motivation to write this review.
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