Jing-Hua Tian

The widespread use of Ni‐rich LiNi _0.8 Co _0.1 Mn _0.1 O ₂ (NCM811) cathodes in high‐energy batteries remains limited by structural degradation, side reactions, and oxygen release, yet most modification strategies prove incompatible with commercial materials. This work presents a facile solid‐state method that achieves synergistic cerium ion (Ce ³⁺ ) doping and CeO ₂ coating on commercial NCM811 by mixing with CeO ₂ nanoparticles followed by calcination. Structural and morphological analyses confirm Ce incorporation into the near‐surface lattice and the formation of a nanoscale CeO ₂ layer without disturbing the layered framework. Electrochemical tests demonstrate that the optimal 1 wt.% Ce‐modified sample exhibits superior rate capability and long‐term stability, retaining 82.04% of its initial capacity after 500 cycles at 1 C, compared to 74.10% for pristine, owing to suppressed cation mixing, enhanced structural stability, and improved Li ⁺ diffusion kinetics. Crucially, differential electrochemical mass spectrometry shows Ce modification curtails O ₂ release and reduces H ₂ and CO ₂ generation across various rates, effectively mitigating gas evolution associated with safety degradation. Accelerating rate calorimetry further confirms delayed thermal runaway and improved adiabatic stability. Overall, this work establishes a scalable post‐treatment route to simultaneously boost the electrochemical performance and safety of commercial nickel‐rich cathodes, offering a practical solution for next‐generation lithium‐ion batteries.

The stability of aqueous zinc‐ion batteries (AZIBs) is compromised by uncontrolled dendrite growth and parasitic side reactions, largely attributed to the high reactivity of interfacial water within the electric double layer (EDL). Regulating the composition of interfacial water emerges as a key strategy for stabilizing AZIBs, this task is fraught with substantial complexities owing to the dynamic and intricate nature of the EDL microenvironment. Here, we introduce a zincophilic structure additive to reconstruct the Zn ²⁺ solvation shell and enforce interfacial water regulation, which effectively suppresses parasitic side reactions and mitigates cathode dissolution. In situ Raman spectroscopy revealed the dynamic evolution of interfacial water, demonstrating that 4‐hydroxy‐L‐proline reconstructs the interfacial hydrogen‐bond network to create a Zn ²⁺ ‐enriched interface with stable Zn ²⁺ flux, promoting the stabilization of the interface. In the optimized electrolyte, Zn//Zn cells achieve exceptional cycling stability exceeding 8000 h; Zn//Cu asymmetric cells achieve an average Coulombic efficiency of 99.71% over 4000 cycles; and Zn//MnO ₂ full cells exhibit stable cycling for 4000 cycles. This work provides a fundamental insight for interfacial water management in high‐performance AZIBs.

The oxygen reduction reaction (ORR) constitutes a central process in electrochemical energy conversion technologies such as fuel cells and metal‐air batteries, yet it is severely limited by sluggish kinetics and large overpotentials. Beyond catalyst design, electrolyte regulation plays a critical role in determining ORR activity. In this study, through a combination of kinetic measurements, spectroscopic analyses, and theoretical calculations, we demonstrate that ORR in the choline chloride (ChCl)‐based deep eutectic solvent (DES) Ethaline is thermodynamically more favorable but kinetically more constrained than in ionic liquids. The introduction of O ₂ is found to substantially perturb the intrinsic hydrogen‐bond network of the DES, while the hydrogen‐bonded environment in turn facilitates the activation of O ₂ toward reduction. On this basis, we propose a novel “hydrogen‐bond network‐activated O ₂ ” mechanism for ORR in DESs, which can be classified as a CEC pathway, wherein O ₂ undergoes a solvent‐induced activation step prior to electron transfer in electrolytes featuring complex hydrogen‐bond networks such as Ethaline. This mechanism provides new insights into electrolyte regulation of ORR and opens new avenues for the design of efficient electrocatalytic systems.

Electrocatalytic CO2 reduction reaction (CO2RR) for CH4 production presents a promising strategy to address carbon neutrality, and the incorporation of a second metal has been proven effective in enhancing catalyst performance. Nevertheless, there remains limited comprehension regarding the fundamental factors responsible for the improved performance. Herein, the critical role of Pd in electrocatalytic CO2 reduction to CH4 on Cu-based catalysts has been revealed at a molecular level using in situ surface-enhanced Raman spectroscopy (SERS). A “borrowing” SERS strategy has been developed by depositing Cu–Pd overlayers on plasmonic Au nanoparticles to achieve the in situ monitoring of the dynamic change of the intermediate during CO2RR. Electrochemical tests demonstrate that Pd incorporation significantly enhances selectivity toward CH4 production, and the Faradaic efficiency (FE) of CH4 is more than two times higher than that for the catalysts without Pd. The key intermediates, including *CO2−, *CO, and *OH, have been directly identified under CO2RR conditions, and their evolution with the electrochemical environments has been determined. It is found that Pd incorporation promotes the activation of both CO2 and H2O molecules and accelerates the formation of abundant active *CO and hydrogen species, thus enhancing the CH4 selectivity. This work offers fundamental insights into the understanding of the molecular mechanism of CO2RR and opens up possibilities for designing more efficient electrocatalysts.

Zinc-air batteries (ZABs) belong to the category of metal-air batteries, with high theoretical energy density, safety, and low cost. Nevertheless, there are still many challenges that need to be solved for the practical application of ZABs, including high overpotential, poor cycle life, and so on. This article first briefly introduced the principle of ZABs, covering the key components, functions of each element, and challenges faced by the system. Subsequently, seven methods for studying ZABs in-situ or operando were introduced, including X-ray computed tomography (XCT), optical microscopy imaging (OMI), transmission electron microscopy (TEM), nuclear magnetic resonance imaging (MRI), X-ray diffraction (XRD), Raman spectroscopy, and X-ray absorption spectroscopy (XAS), accompanied by specific research examples. The future perspectives of ZAB characterization have also been discussed.