Building insights into the structure-performance relationship of catalysts has been emphasized recently. However, it remains a challenge due to catalysts' various and complex structures, especially the easily overlooked influence of the support material. Here, we reveal the crucial influences of boron introduction on synthesizing 3D carbon nanotube monoliths with embedded multistate Co metals, i.
View Article and Find Full Text PDFAqueous biphasic systems (ABSs) with water-in-salt electrolytes are gaining significant attention for their role in aqueous biphasic interphase studies, particularly in energy storage devices. Aqueous salt-salt biphasic electrolytes are considered a promising alternative to replace traditional liquid electrolytes commonly used in battery technologies, for example, membrane-less redox flow batteries, owing to their low cost and high ionic conductivity. However, the stability of the interphase over time must be considered, as it can impact the long-term electrochemical performance in various applications.
View Article and Find Full Text PDFDeveloping energy- and time-efficient strategies to derive high-performance non-precious electrocatalysts for anodic oxygen evolution reaction (OER), especially stably working at industrial-demanding current density, is still a big challenge. In this work, a concise molten salt erosion scenario was devised to rapidly modulate the smooth surface of the commercial NiMo foam substrate into the rough, electronically coupled, and hierarchically porous Ni/Fe/Mo(oxy)hydroxide catalyst layer assembled by the nanosphere array. This self-supported catalyst is super-hydrophilic for the alkaline electrolyte and distinguished by a balanced Mo leaching/surface-readsorption process to tune the metal d band center and electronic perturbation.
View Article and Find Full Text PDFIn recent decades, more than 100,000 scientific articles have been devoted to the development of electrode materials for supercapacitors and batteries. However, there is still intense debate surrounding the criteria for determining the electrochemical behavior involved in Faradaic reactions, as the issue is often complicated by the electrochemical signals produced by various electrode materials and their different physicochemical properties. The difficulty lies in the inability to determine which electrode type (battery vs.
View Article and Find Full Text PDFA water-in-salt electrolyte is a highly concentrated aqueous solution (i.e., 21 mol LiTFSI in 1 kg H O) that reduces the number of water molecules surrounding salt ions, thereby decreasing the water activity responsible for decomposition.
View Article and Find Full Text PDFSuperconcentrated aqueous electrolytes have recently emerged as a new class of electrolytes, called water-in-salt electrolytes. They are distinguished, in both weight and volume, by a quantity of salt greater than water. Currently, these electrolytes are attracting major interest, particularly for application in aqueous rechargeable batteries.
View Article and Find Full Text PDFThe essence of any electrochemical system is engraved in its electrical double layer (EDL), and we report its unprecedented reorganization by the structural isomerism of molecules, with a direct consequence on their energy storage capability. Electrochemical and spectroscopic analyses in combination with computational and modelling studies demonstrate that an attractive field-effect due to the molecule's structural-isomerism, in contrast to a repulsive field-effect, spatially screens the ion-ion coulombic repulsions in the EDL and reconfigures the local density of anions. In a laboratory-level prototype supercapacitor, those with β-structural isomerism exhibit nearly 6-times elevated energy storage compared to the state-of-the-art electrodes, by delivering ∼535 F g at 1 A g while maintaining high performance metrics even at a rate as high as 50 A g.
View Article and Find Full Text PDFAqueous batteries are regaining interest, thanks to the extended working stability voltage window in a highly concentrated electrolyte, namely the water-in-salt electrolyte. A solid-electrolyte interphase (SEI) forms on the negative electrode to prevent water access to the electrode surface. However, we further reported that the formed SEI layer was not uniform on the surface of the glassy carbon electrode.
View Article and Find Full Text PDFElectrochemical water splitting to hydrogen fuel is highly desirable yet challenging mainly limited by sluggish cathodic oxygen evolution reaction (OER). Urea electrolysis can produce hydrogen more energy-savingly by replacing OER process with urea oxidation reaction (UOR) due to favorable thermodynamic potential, however lacking efficient UOR catalysts restricts the industrial application. Here we reported novel NiMo-based nanorods, Ni/NiMoN/MoO, by thermal ammonolysis of NiMo-based precursor as excellent catalyst for OER and hydrogen evolution reaction (HER) with small overpotentials of 252 mV, and 103 mV to achieve a current density of 10 mA cm in 1.
View Article and Find Full Text PDFMagneto-phosphorescent d-f coordination polymer nanoparticles (f-CPPs) were conveniently synthesized by phosphorescent carboxyl-functionalized iridium complexes as building blocks and magnetic Gd(III) ions as metallic nodes. They reveal uniform hollow spheres with an average diameter of around 60 nm and wall thickness of about 10 nm. Water soluble f-CPPs were obtained by polyvinylpyrolidone modification (denoted as f-CPPs@PVP), which had an intense red phosphorescence, moderate longitudinal relaxivity (r(1)) and low cytotoxicity.
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