It is well known that the superconducting transition temperature (Tc) of cuprate superconductors can be enhanced by varying certain structural and electronic parameters, such as the flatness of the CuO2 planes or thei...
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It is well known that the superconducting transition temperature (Tc) of cuprate superconductors can be enhanced by varying certain structural and electronic parameters, such as the flatness of the CuO2 planes or their doping level. We determine the uniaxial and hydrostatic pressure derivatives of Tc in the structurally simple tetragonal compound HgBa2CuO4+δ near optimal doping. Our results provide experimental evidence for two further methods to enhance Tc: (i) reducing the area of the CuO2 planes, and (ii) increasing the separation of the CuO2 planar groups. Tc is found to couple much more strongly to the ratio c/a of the lattice constants than to the unit cell volume. A comparison with prior results for structurally more complicated cuprates reveals a general trend of uniaxial pressure derivatives with Tc.
Cyclic ether, such as 1,3-dioxolane (DOL), are promising solvent for low-temperature electrolytes because of the low freezing point. Their use in electrolytes, however, is severely limited since it easily polymerizes ...
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Cyclic ether, such as 1,3-dioxolane (DOL), are promising solvent for low-temperature electrolytes because of the low freezing point. Their use in electrolytes, however, is severely limited since it easily polymerizes in the presence of lithium inorganic salts. The trace water plays a key role via providing the source (proton) for chain initiation, which has, unfortunately, been neglected in most cases. In this work, we present an electrophile, trimethylsilyl isocyanate (Si−NCO), as the water scavenger, which eliminates moisture by a nucleophilic addition reaction. Si−NCO allows DOL to maintain liquid over a wide temperature range even in high-concentration electrolyte. Electrolyte with Si−NCO additive shows promising low-temperature performance. Our finding expands the use of cyclic ether solvents in the presence of inorganic salts and highlights a large space for unexplored design of water scavenger with electrophilic feature for low-temperature electrolytes.
Continuous hydrogen-bond-network in aqueous electrolytes can lead to uncontrollab.e hydrogen transfer, and combining the interfacial parasitic electron consumption cause the side reaction in aqueous zinc metal batteri...
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Continuous hydrogen-bond-network in aqueous electrolytes can lead to uncontrollab.e hydrogen transfer, and combining the interfacial parasitic electron consumption cause the side reaction in aqueous zinc metal batteries (AZMBs). Herein, hydrogen/electron amphiphilic bi-functional 1,5-Pentanediol (PD) molecule was introduced to stabilize the electrode/electrolyte interface. Stronger proton affinity of -OH in PD can break bulk-H 2 O hydrogen-bond-network to inhibit the activity of water, and electron affinity can enhance electron acceptation capability, which ensures that PD is preferentially bound to electrode material over H 2 O. Besides, the participation of PD in the Zn 2+ solvation structure reduces water content at the solid–liquid interface and promotes uniform deposition process by optimizing Zn 2+ de-solvation energy. Accordingly, dense and vertical zinc texture based on intrinsic steric hindrance effect of PD and formed SEI protective layer to induce stable Zinc anode-electrolyte interface. Moreover, an organic–inorganic shielding water layer was formed at the cathode side to suppress vanadium dissolution in vanadium Oxide. Consequently, Zn//Zn symmetric cell could cycle for more than 5600 hours at 1 mAh cm −2 @1 mA cm −2 (more than 250 hours at 50 °C). Besides, the VO 2 and I 2 cathode all achieved stable cycling performance and former pouch cell could reach average capacity of 0.13 Ah.
The S-scheme heterojunction is flourishing in photocatalysis because it concurrently realizes separated charge carriers and sufficient redox ability. Steady-state charge transfer has been confirmed by other methods. H...
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The S-scheme heterojunction is flourishing in photocatalysis because it concurrently realizes separated charge carriers and sufficient redox ability. Steady-state charge transfer has been confirmed by other methods. However, an essential part, the transfer dynamics in S-scheme heterojunctions, is still missing. To compensate, a series of cadmium sulfide/pyrene- alt -difluorinated benzothiadiazole heterojunctions were constructed and the photophysical processes were investigated with femtosecond transient absorption spectroscopy. Encouragingly, an interfacial charge-transfer signal was detected in the spectra of the heterojunction, which provides solid evidence for S-scheme charge transfer to complement the results from well-established methods. Furthermore, the lifetime for interfacial charge transfer was calculated to be ca. 78.6 ps. Moreover, the S-scheme heterojunction photocatalysts exhibit higher photocatalytic conversion of 1,2-diols and H 2 production rates than bare cadmium sulfide.
Crystalline porous organic salts (CPOSs), as an emerging class of porous organic materials, combining the uniform microporous system and distinct polarized channels, have become a highly evolving field of important cu...
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Crystalline porous organic salts (CPOSs), as an emerging class of porous organic materials, combining the uniform microporous system and distinct polarized channels, have become a highly evolving field of important current interest. The unique ionic bond of a CPOS endows the confined channels with high polarity, making CPOSs distinct from other organic frameworks. CPOSs show many fascinating properties, such as proton conductivity and fast transport of polar molecules, which involve the interaction between highly polarized guest molecules and host frameworks. Substantial progress has been made in the synthesis and applications of CPOSs. Herein, an overview is provided to impart a comprehensive understanding of the link between the synthetic approaches and the resultant microporous structure, the structure-function correlation and the state-of-the-art applications of CPOSs. The enhanced mass-transport performance of hierarchically porous structure in combination with the intrinsic polarized channels of CPOSs is very promising to create new applications and contribute to a new research upsurge. The perspective to construct porous hierarchy within the crystalline porous organic salts is assessed and will open a new research avenue. In the conclusion, the current challenges on the synthesis, structural regulation, and applications of CPOSs and the future of hierarchically porous crystalline organic salts are discussed.
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