Energy & Environmental Science最新文献

The importance of the solid–electrolyte-interphase (SEI) is well-established in lithium-ion (Li-ion) batteries, but the technical story behind its formation remains incomplete. Current research has largely focused on the nature of the deposited layer, while the formation dynamics, particularly those occurring in the solution phase, remain elusive. Here, by employing operando infrared fiber evanescent wave spectroscopy (IR-FEWS) to conduct real-time monitoring of the chemical dynamics of ethylene carbonate-based electrolytes and graphite anodes, we reveal that the assembly of the SEI layer follows a classical heterogeneous nucleation and growth process under appropriate kinetic constraints. Our findings, supported by various other in situ/ex situ techniques, show that during charging, the newly generated species (e.g. lithium ethylene dicarbonate (LEDC) and Li₂CO₃), that are destined for the SEI, can also diffuse away from the graphite–electrolyte interface into the electrolyte. The deposition of the species occurs via a heterogeneous nucleation process with the low-solubility inorganic species (e.g. Li₂CO₃) preferentially nucleating on the graphite surface, followed by more-soluble organic species (e.g. LEDC). Limiting diffusion to promote the deposition is crucial for facilitating efficient SEI formation with competitive deposition kinetics depending not only on the charging rate and temperature, but also the electrolyte quantity. When the formation parameter-space is intentionally modified by employing a high current pulse during initial charging followed immediately by an ageing step, a more stable SEI with lower resistance is developed, leading to longer lifetimes for the Li-ion pouch cells prepared with this new protocol. Collectively, these findings deepen our mechanistic understanding of SEI formation from the “solution” phase perspective and offer an enriched framework for defining initial charging protocols for battery manufacturing.

Zinc–air self-charging batteries integrate energy harvesting, storage, and conversion by utilizing ambient oxygen to drive spontaneous redox reactions, but their practical application is limited by sluggish self-charging kinetics and unstable aqueous interfaces. Here we introduce a hybrid electrolyte of N,N-dimethylacetamide (DMAC) with 10 vol% H₂O that achieves rapid and durable Zn–air self-rechargeability. DMAC offers low vapor pressure, high oxygen solubility, and resistance to reactive oxygen species, while the controlled water content supplies protons essential for Zn²⁺ intercalation. This synergy drives the formation of a porous, oxygen-permeable interfacial layer that accelerates Zn²⁺ transport and continuous oxygen reduction. Consequently, the batteries self-charge to 0.9 V within 13 min in an oxygen atmosphere, deliver a record cumulative discharge capacity of 37 392 mAh g⁻¹ over 200 cycles, and maintain high-rate capability. This electrolyte design overcomes intrinsic limitations of aqueous systems and establishes a pathway toward safe, high-performance air self-charging batteries.

The global crises of resource scarcity, energy shortages, and environmental degradation demand innovative solutions for sustainable development. Solar-driven interfacial evaporation (SIE) has emerged as a transformative technology for recovering resource/energy from seawater or wastewater. Despite SIE's high evaporation efficiency at the gas–liquid interface, significant challenges persist, including volatile organic compound (VOC) enrichment, selective separation limitations, and energy trade-offs in multifunctional systems. Accordingly, this work provides a comprehensive overview of recent SIE systems for resource/energy recovery while establishing novel dynamics and thermodynamics frameworks to guide their design and application. By shifting the paradigm from “water purification” to a “resource/energy factory”, SIE systems can offer a promising pathway toward carbon neutrality.

Pseudocapacitive materials store electrochemical energy through fast and reversible surface charge transfer reactions. Titanium carbide MXenes are two-dimensional materials which have shown redox or intercalation pseudocapacitive properties depending on the electrolyte. Nevertheless, the intrinsic pseudocapacitive charging mechanism in individual MXene flakes remains unresolved. Here, we employ in situ scanning transmission X-ray microscopy (STXM) to map the local chemical changes in individual Ti₃C₂T_x MXene flakes during spontaneous and electrochemical intercalation of protons and lithium ions in aqueous electrolytes. Our investigations reveal that proton and lithium-ion intercalation induces a reduction and an oxidation, respectively, of the titanium atoms in the MXene. This difference reveals a profoundly different chemical origin between redox and intercalation pseudocapacitive processes. By elucidating the interplay between ion hydration, MXene surface chemistry and flake morphology, our study highlights the relevance of chemical imaging in single entities for the fundamental understanding of electrochemical charge storage mechanisms.