Main observation and conclusion The application of lithium-ion batteries in cold climates has been hindered due to the decline in performance at low temperatures. The increased de-solvation energy and formation of Li dendrites at the anode surface emerge as the major challenges, which rely on the development of stable anode and compatible electrolytes. Herein, a self-healing GaInSn liquid metal (LM) based electrode coupled with a multi-solvent electrolyte is proposed toward reversible Li-storage at low temperatures. By using methyl butyrate (MB) as a co-solvent in 1 mol·L –1 LiTFSI of ethylene carbonate and diethyl carbonate, the electrolyte viscosity decreases from 52.07 to 13.75 mPa·s, while the ionic conductivity increases from 1.38 to 3.44 mS·cm –1 at –20 °C. Moreover, the Li/MXene@LM cells can display a discharge capacity of 500 mAh·g –1 , with capacity retention of 78% at –20 °C after 120 cycles. It is disclosed that a uniform LiF-rich solid electrolyte interface (SEI) layer on the anode is formed upon the addition of MB, which promotes the desolvation of Li ions at the interface of electrode/electrolyte especially at low temperatures. These results prove that MB as the co-solvent is well compatible with LM based anodes and holds great potential for the exploration of low-temperature energy devices.
Aqueous zinc-ion batteries (ZIBs) have garnered significant attention due to their high energy, intrinsic safety, and environmental friendliness. NASICON-type compounds are promising cathode candidates in aqueous batteries due to their high ionic conductivity , and high operating voltage. However, these materials, e.g., Na 3 V 2 (PO 4 ) 3 , suffer from inevitable structural degradation and dissolution in aqueous electrolytes, thus hampering their practical performance in aqueous batteries. Interfacial chemistry modulation by electrolyte engineering is beneficial for stabilizing Zn metal anode and high-voltage cathodes in ZIBs . Herein, the interfacial chemistries in an engineered non-concentrated aqueous electrolyte by co-solvent strategy are reported, which synergistically enables high reversibility of Zn anode and long cycling stability of Na 3 V 2 (PO 4 ) 3 cathode. Consequently, the Zn||Na 3 V 2 (PO 4 ) 3 full-cell exhibits high Coulombic efficiency (∼99.3% in average) with a prolonged cycling life, which can be ascribed to the synergistic-effect of the solid-electrolyte interphases with unique organic/inorganic hybrid structures on the electrodes. This work discloses the structures of the interphases formed on the electrodes induced by co-solvent strategy in aqueous electrolytes and their working mechanisms in stabilizing the aqueous Zn batteries, which will guide the future design of advanced aqueous electrolytes with unique interfacial chemistries for batteries.
The processing solvents strongly impact the crystallization and optoelectronic properties of the resultant perovskites. However, limited by the solubility of perovskites, available processing solvents for perovskite light-emitting diodes (PeLEDs) are restricted to only a few strongly coordinated and polar solvents, such as dimethyl sulfoxide (DMSO). The strong coordination capability of DMSO with Pb 2+ excessively affects the crystallization of perovskites, often necessitating anti-solvent engineering to regulate the crystallization process. Here, a strategy of weakly coordinated co-solvent comprising 2-methoxyethanol (2-ME) and propylene carbonate (PC) is proposed to fabricate quasi-2Dperovskites and PeLEDs. This co-solvent exhibits synergistic properties—complementary coordination capability and dielectric constant—yielding superior solvation capability compared to either solvent alone. Crucially, the tunable, moderate solvation strength of the 2-ME:PC mixture facilitates perovskites crystallization while suppressing detrimental low-dimensional phase growth, enabling anti-solvent-free fabrication of high-quality formamidinium-based quasi-2D perovskites. Employing this optimized co-solvent, pure green PeLEDs are achieved that comply with Rec. 2020 standards, boasting a remarkable external quantum efficiency of 26.2%. This work presents an effective strategy for the facile fabrication of high-performance PeLEDs, while also guiding the selection of additional perovskite processing solvents.
危险品化学品经营许可证（带存储）