High-Entropy Rock-Salt Surface Layer Stabilizes the Ultrahigh-Ni Single-Crystal Cathode.

Single-crystalline Ni-rich layered oxides are one of the most promising cathode materials for lithium-ion batteries due to their superior structural stability. However, sluggish lithium-ion diffusion kinetics and interfacial issues hinder their practical applications. These issues intensify with increasing Ni content in the ultrahigh-Ni regime (≥90%), significantly threatening the practical viability of the single-crystalline strategy for ultrahigh-Ni layered oxide cathodes.

Nanolaminated Ternary Transition Metal Carbide (MAX Phase)-Derived Core-Shell Structure Electrocatalysts for Hydrogen Evolution and Oxygen Evolution Reactions in Alkaline Electrolytes.

The development of abundant, cheap, and highly active catalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is important for hydrogen production. Nanolaminate ternary transition metal carbides (MAX phases) and their derived two-dimensional transition metal carbides (MXenes) have attracted considerable interest for electrocatalyst applications. Herein, four new MAX@MXene core-shell structures (TaCoC@TaCT, TaNiC@TaCT, NbCoC@NbCT, and NbNiC@NbCT), in which the core region is Co/Ni-MAX phases while the edge region is MXenes, have been prepared.

Determination of Crystallographic Orientation and Exposed Facets of Titanium Oxide Nanocrystals.

Titanium dioxide (TiO ) nanocrystals have attracted great attention in heterogeneous photocatalysis and photoelectricity fields for decades. However, contradicting conclusions on the crystallographic orientation and exposed facets of TiO nanocrystals frequently appear in the literature. Herein, using anatase TiO nanocrystals with highly exposed {001} facets as a model, the misleading conclusions that exist on anatase nanocrystals are clarified.

Hydrogenated CsAgBiBr for significantly improved efficiency of lead-free inorganic double perovskite solar cell.

Development of lead-free inorganic perovskite material, such as CsAgBiBr, is of great importance to solve the toxicity and stability issues of traditional lead halide perovskite solar cells. However, due to a wide bandgap of CsAgBiBr film, its light absorption ability is largely limited and the photoelectronic conversion efficiency is normally lower than 4.23%.

In CH NH PbI Perovskite Film, the Surface Termination Layer Dominates the Moisture Degradation Pathway.

Theoretical studies have shown that surface terminations, such as MAI or PbI layers, greatly affect the environmental stability of organic-inorganic perovskite. However, until now, there has been little effort to experimentally detect the existence of MAI or PbI terminations on MAPbI grains, let alone disclose their effects on the humidity degradation pathway of perovskite solar cell. Here, we successfully modified and detected the surface terminations of MAI and PbI species on polycrystalline MAPbI films.