2D MXene/MBene Superlattice with Narrow Bandgap as Superior Electrocatalyst for High-Performance Lithium-Oxygen Battery.

Lithium-oxygen (Li-O) battery with large theoretical energy density (≈3500 Wh kg) is one of the most promising energy storage and conversion systems. However, the slow kinetics of oxygen electrode reactions inhibit the practical application of Li-O battery. Thus, designing efficient electrocatalysts is crucial to improve battery performance.

Energy level regulation of anions hydrogen bond effects to construct a stable solid electrolyte interface for a high-stability lithium metal anode.

An intermolecular hydrogen bond between 2,5-dihydroxyterephthalic acid and the anions in the Li solvation shell is constructed to promote the formation of a LiF-rich SEI on a metallic Li electrode. Li metal batteries with improved cyclability (140 cycles under an N/P ratio of 4.9) and high capacity retention (90%) are eventually obtained.

Controllable Regulation of the Oxygen Redox Process in Lithium-Oxygen Batteries by High-Configuration-Entropy Spinel with an Asymmetric Octahedral Structure.

Designing bifunctional electrocatalysts to boost oxygen redox reactions is critical for high-performance lithium-oxygen batteries (LOBs). In this work, high-entropy spinel (CoMnNiFeCr)O (HEOS) is fabricated by modulating the internal configuration entropy of spinel and studied as the oxygen electrode catalyst in LOBs. Under the high-entropy atomic environment, the Co-O octahedron in spinel undergoes asymmetric deformation, and the reconfiguration of the electron structure around the Co sites leads to the upward shift of the d-orbital centers of the Co sites toward the Fermi level, which is conducive to the strong adsorption of redox intermediate LiO on the surface of the HEOS, ultimately forming a layer of a highly dispersed LiO thin film.

Structure and Charge Regulation Strategy Enabling Superior Cycling Stability of Ni-Rich Cathode Materials.

Ni-rich layered oxides LiNiCoMnO (NCMs, > 0.8) are the most promising cathode candidates for Li-ion batteries because of their superior specific capacity and cost affordability. Unfortunately, NCMs suffer from a series of formidable challenges such as structural instability and incompatibility with commonly used electrolytes, which seriously hamper their practical applications on a large scale.

Adjusting Li Solvation Structures via Dipole-Dipole Interaction to Construct Inorganic-Rich Interphase for High-Performance Li Metal Batteries.

Practical applications of lithium metal batteries are limited by unstable solid electrolyte interphase (SEI) and uncontrollable dendrite Li deposition. Regulating the solvation structure of Li via modifying electrolyte components enables optimizing the structure of the SEI and realizing dendrite-free Li deposition. In this work, it is found that the ionic-dipole interactions between the electron-deficient B atoms in lithium oxalyldifluoro borate (LiDFOB) and the O atoms in the DME solvent molecule can weaken the interaction between the DME molecule and Li, accelerating the desolvation of Li.

Bimetallic MXene with tailored vanadium d-band as highly efficient electrocatalyst for reversible lithium-oxygen battery.

Lithium-oxygen (Li-O) battery possesses high theoretical energy density of ∼ 3500 Wh kg, yet the sluggish kinetics of oxygen redox reactions hinder its practical application. Herein, TiVC bimetallic MXene solid solution is prepared as the efficient electrocatalyst for Li-O battery. The results of experiment and theoretical calculations reveal that through the formation of Ti-C-V bond in TiVC, electrons transfer from V site to Ti site enhances electron delocalization of V sites, which causes the upshift of d band center of V site and strengthens the adsorption of intermediate products (LiO) on TiVC electrode surface.