Dendrite-Free and High-Rate Potassium Metal Batteries Sustained by an Inorganic-Rich SEI.

Potassium metal battery is an appealing candidate for future energy storage. However, its application is plagued by the notorious dendrite proliferation at the anode side, which entails the formation of vulnerable solid electrolyte interphase (SEI) and non-uniform potassium deposition on the current collector. Here, this work reports a dual-modification design of aluminum current collector to render dendrite-free potassium anodes with favorable reversibility. This work achieves to modulate the electronic structure of the designed current collector and accordingly attain an SEI architecture with robust inorganic-rich constituents, which is evidenced by detailed cryo-EM inspection and X-ray depth profiling. The thus-produced SEI manages to expedite ionic conductivity and guide homogeneous potassium deposition. Compared to the potassium metal cells assembled using typical aluminum current collector, cells based on the designed current collector realize improved rate capability (maintaining 400 h under 50 mA cm-2 ) and low-temperature durability (stable operation at -50 °C). Moreover, scalable production of the current collector allows for the sustainable construction of high-safety potassium metal batteries, with the potential for reducing the manufacturing cost.

Rationalized Electroepitaxy toward Scalable Single-Crystal Zn Anodes.

Electroepitaxy is recognized as an effective approach to prepare metal electrodes with nearly complete reversibility. Nevertheless, large-scale manipulation is still not attainable owing to complicated interfacial chemistry. Here, the feasibility of extending Zn electroepitaxy toward the bulk phase over a mass-produced mono-oriented Cu(111) foil is demonstrated. Interfacial Cu-Zn alloy and turbulent electroosmosis are circumvented by adopting a potentiostatic electrodeposition protocol. The as-prepared Zn single-crystalline anode enables stable cycling of symmetric cells at a stringent current density of 50.0 mA cm-2 . The assembled full cell further sustaines a capacity retention of 95.7% at 5.0 A g-1 for 1500 cycles, accompanied by a controllably low N/P ratio of 7.5. In addition to Zn, Ni electroepitaxy can be realized by using the same approach. This study may inspire rational exploration of the design of high-end metal electrodes.

Synthesis, crystal structure, vibrational spectra and theoretical calculation of 1-carboxymethyl-3-methylimidazolium chloride.

In this paper, the structure of 1-carboxymethyl-3-methylimidazolium chloride was studied by X-ray diffraction, density functional theory, and FT-IR and Raman spectroscopic techniques for the first time. Title compound crystallizes in the orthorhombic space group Pca2(1) with the cell dimensions a=13.445 (6) Å, b=6.382 (3) Å, c=9.727 (5) Å and V=834.6 (7) Å(3). All the geometrical parameters have been calculated using by B3LYP with 6-311G++(d,p) basis set. Optimized geometries have been compared with the experimental data, and the hydrogen bond and short contact interactions were discussed. The vibrational frequencies, infrared intensities and Raman scattering activities of the title compound were calculated at the same level. The observed bands were assigned based on the theoretical calculations. The scaled vibrational frequencies seem to coincide with the experimental data with acceptable deviations.

Calf thymus DNA binding studies of the new neodymium-naproxen complex.

Fluorescence spectroscopy in combination with UV absorption spectroscopy was carried out to investigate the interaction between the neodymium-naproxen complex (Nd-NAP) and calf thymus DNA (ctDNA). The experimental results showed that Nd-NAP intercalated with the ctDNA base pairs. Analysis of fluorescence quenching data of Nd-NAP by ctDNA at different temperatures using a Stern-Volmer equation revealed that dynamic and static quenching occurred simultaneously. The binding constants and the number of binding sites at 293 and 310 K were obtained as 2.904 × 10(4) L mol(-1), 1.172 and 2.432 × 10(4) L mol(-1), 1.143, respectively. The thermodynamic parameters ΔG, ΔH, and ΔS calculated at different temperatures indicated that hydrogen bonding and van der Waals force were the main binding forces.