High-Performance Nickel-Bismuth Oxide Electrocatalysts Applicable to Both the HER and OER in Alkaline Water Electrolysis.

As an electrocatalyst for water electrolysis, nickel oxide (NiO) has received significant attention due to its cost-effectiveness and high reactivity among non-noble-metal-based catalytic materials. However, NiO still exhibits poor alkaline hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) kinetics compared to conventional noble metal-based catalysts. This is because NiO has a strong interaction with protons for the HER and too low free energy of the OH* state, resulting in slower rate-determining step (RDS) kinetics for the OER.

Galvanic hydrogenation reaction in metal oxide.

Rational reforming of metal oxide has a potential importance to modulate their inherent properties toward appealing characteristics for various applications. Here, we present a detailed fundamental study of the proton migration phenomena between mediums and propose the methodology for controllable metal oxide hydrogenation through galvanic reactions with metallic cation under ambient atmosphere. As a proof of concept for hydrogenation, we study the role of proton adoption on the structural properties of molybdenum trioxide, as a representative, and its impact on redox characteristics in Li-ion battery (LiB) systems using electrochemical experiments and first-principles calculation.

An Inorganic-Rich SEI Layer by the Catalyzed Reduction of LiNO Enabled by Surface-Abundant Hydrogen Bonding for Stable Lithium Metal Batteries.

Lithium (Li) metal anodes (LMAs) are promising anode candidates for realizing high-energy-density batteries. However, the formation of unstable solid electrolyte interphase (SEI) layers on Li metal is harmful for stable Li cycling; hence, enhancing the physical/chemical properties of SEI layers is important for stabilizing LMAs. Herein, thiourea (TU, CH N S) is introduced as a new catalyzing agent for LiNO reduction to form robust inorganic-rich SEI layers containing abundant Li N.

Realization of a 594 Wh kg Lithium-Metal Battery Using a Lithium-Free V O Cathode with Enhanced Performances by Nanoarchitecturing.

To realize a high-energy lithium metal battery (LMB) using a high-capacity Li-free cathode, in this work, nanoplate-stacked V O with dominantly exposed (010) facets and a relatively short [010] length is proposed to be used as a cathode. The V O nanostructure can be fabricated via a modified hydrothermal method, including a Li crystallization inhibitor, followed by heat treatment. In particular, the enlargement of the favorable Li diffusion pathway in the [010] direction and the formation of a robust hierarchical nanoplate-stacked structure in the modified V O improves the electrochemical kinetics and stability; as a result, the nanoplate-stacked V O electrode exhibits a higher capacity and rate performance (258 mAh g at 50 mA g [0.

Spontaneous and Selective Nanowelding of Silver Nanowires by Electrochemical Ostwald Ripening and High Electrostatic Potential at the Junctions for High-Performance Stretchable Transparent Electrodes.

Metal nanowires have been gaining increasing attention as the most promising stretchable transparent electrodes for emerging field of stretchable optoelectronic devices. Nanowelding technology is a major challenge in the fabrication of metal nanowire networks because the optoelectronic performances of metal nanowire networks are mostly limited by the high junction resistance between nanowires. We demonstrate the spontaneous and selective welding of Ag nanowires (AgNWs) by Ag solders via an electrochemical Ostwald ripening process and high electrostatic potential at the junctions of AgNWs.