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Aqueous zinc‐ion batteries are promising alternatives to lithium‐ion batteries due to their cost‐effectiveness and improved safety. However, several challenges, including corrosion, dendrites, and water decomposition at the Zn anode, hinder their performance. Herein, an approach is proposed, that deviates from the conventional design by adding water into a propylene carbonate‐based organic electrolyte to prepare a non‐flammable “water‐in‐organic” electrolyte. The chaotropic salt Zn(ClO₄)₂exploits the Hofmeister effect to promote the miscibility of immiscible liquid phases. Interactions between propylene carbonate and water restrict water activity and mitigate unfavorable reactions. This electrolyte facilitates preferential Zn (002) deposition and the formation of solid electrolyte interphase. Consequently, the “water‐in‐organic” electrolyte achieves a 99.5% Coulombic efficiency at 1 mA cm⁻²over 1000 cycles in Zn/Cu cells, and constant cycling over 1000 h in Zn/Zn symmetric cells. A Na_0.33V₂O₅/Zn battery exhibits impressive cycling stability with a capacity of 175 mAh g⁻¹for 800 cycles at 2 A g⁻¹. Additionally, this electrolyte enables sustainable cycling across a wide temperature range from −20 to 50 °C. The design of a “water‐in‐organic” electrolyte employing a chaotropic salt presents a potential strategy for high‐performance electrolytes in zinc‐ion batteries with a large stability window and a wide temperature range.

The impact ofin situelectrooxidation in a Ni₃N electrocatalyst on its hydrogen evolution activity and electrochemical stability was investigated in alkaline media.

Calculations with high accuracy for atomic and inter-atomic properties, such as nuclear magnetic resonance (NMR) spectroscopy and bond dissociation energies (BDEs) are valuable for pharmaceutical molecule structural analysis, drug exploration, and screening. It is important that these calculations should include relativistic effects, which are computationally expensive to treat. Non-relativistic calculations are less expensive but their results are less accurate. In this study, we present a computational framework for predicting atomic and inter-atomic properties by using machine-learning in a non-relativistic but accurate and computationally inexpensive framework. The accurate atomic and inter-atomic properties are obtained with a low dimensional deep neural network (DNN) embedded in a fragment-based graph convolutional neural network (F-GCN). The F-GCN acts as an atomic fingerprint generator that converts the atomistic local environments into data for the DNN, which improves the learning ability, resulting in accurate results as compared to experiments. Using this framework, the 13C/1H NMR chemical shifts of Nevirapine and phenol O–H BDEs are predicted to be in good agreement with experimental measurement.

Aqueous zinc metal batteries are emerging as a promising alternative for energy storage due to their high safety and low cost. However, their development is hindered by the formation of Zn dendrites and side reactions. Herein, a macromolecular crowding electrolyte (MCE40) is prepared by incorporating polyvinylpyrrolidone (PVP) into the aqueous solutions, exhibiting an enlarged electrochemical stability window and anti‐freezing properties. Notably, through electrochemical measurements and characterizations, it is discovered that the mass transfer limitation near the electrode surface within the MCE40 electrolyte inhibits the (002) facets. This leads to the crystallographic reorientation of Zn deposition to expose the (100) and (101) textures, which undergo a “nucleation‐merge‐growth” process to form a uniform and compact Zn deposition. Consequently, the MCE40 enables highly reversible and stable Zn plating/stripping in Zn/Cu half cells over 600 cycles and in Zn/Zn symmetric cells for over 3000 hours at 1.0 mA cm⁻². Furthermore, Na_0.33V₂O₅/Zn and α‐MnO₂/Zn full cells display promising capacity and sustained stability over 500 cycles at room and sub‐zero temperatures. This study highlights a novel electrochemical mechanism for achieving preferential Zn deposition, introducing a unique strategy for fabricating dendrite‐free zinc metal batteries.

Aqueous zinc metal batteries are emerging as a promising alternative for energy storage due to their high safety and low cost. However, their development is hindered by the formation of Zn dendrites and side reactions. Herein, a macromolecular crowding electrolyte (MCE40) is prepared by incorporating polyvinylpyrrolidone (PVP) into the aqueous solutions, exhibiting an enlarged electrochemical stability window and anti‐freezing properties. Notably, through electrochemical measurements and characterizations, it is discovered that the mass transfer limitation near the electrode surface within the MCE40 electrolyte inhibits the (002) facets. This leads to the crystallographic reorientation of Zn deposition to expose the (100) and (101) textures, which undergo a “nucleation‐merge‐growth” process to form a uniform and compact Zn deposition. Consequently, the MCE40 enables highly reversible and stable Zn plating/stripping in Zn/Cu half cells over 600 cycles and in Zn/Zn symmetric cells for over 3000 hours at 1.0 mA cm⁻². Furthermore, Na_0.33V₂O₅/Zn and α‐MnO₂/Zn full cells display promising capacity and sustained stability over 500 cycles at room and sub‐zero temperatures. This study highlights a novel electrochemical mechanism for achieving preferential Zn deposition, introducing a unique strategy for fabricating dendrite‐free zinc metal batteries.

Herein, aqueous nitrate (NO₃⁻) reduction is used to explore composition‐selectivity relationships of randomly alloyed ruthenium‐palladium nanoparticle catalysts to provide insights into the factors affecting selectivity during this and other industrially relevant catalytic reactions. NO₃⁻reduction proceeds through nitrite (NO₂⁻) and then nitric oxide (NO), before diverging to form either dinitrogen (N₂) or ammonium (NH₄⁺) as final products, with N₂preferred in potable water treatment but NH₄⁺preferred for nitrogen recovery. It is shown that the NO₃⁻and NO starting feedstocks favor NH₄⁺formation using Ru‐rich catalysts, while Pd‐rich catalysts favor N₂formation. Conversely, a NO₂⁻starting feedstock favors NH₄⁺at ≈50 atomic‐% Ru and selectivity decreases with higher Ru content. Mechanistic differences have been probed using density functional theory (DFT). Results show that, for NO₃⁻and NO feedstocks, the thermodynamics of the competing pathways for N–H and N–N formation lead to preferential NH₄⁺ or N₂production, respectively, while Ru‐rich surfaces are susceptible to poisoning by NO₂⁻feedstock, which displaces H atoms. This leads to a decrease in overall reduction activity and an increase in selectivity toward N₂production. Together, these results demonstrate the importance of tailoring both the reaction pathway thermodynamics and initial reactant binding energies to control overall reaction selectivity.