SearcharxivSearch

arXiv subjects

Shuangying Wei

Publications and source records attributed to Shuangying Wei.

2 recordsLinked to original sources

An Ultrathin Laterally Conductive Mesh Interphase Enables Spatially Extended Zinc Deposition for Aqueous Zinc Batteries

Zn metal anodes often suffer from nonuniform interfacial reactions during cycling, resulting in uneven deposition and dendrite growth. Existing artificial interphases can mitigate side reactions or regulate nucleation, but rarely achieve regulation of the interfacial electron/field distribution to sustain uniform deposition at the evolving Zn/electrolyte interface. Here, we develop an Au mesh interphase (AuMI), an ultrathin two-dimensional Au aerogel network that couples lateral electron redistribution with open pathways for ions. During Zn plating/stripping, the conductive AuMI distributes electron transport across the Zn surface, while its porous mesh preserves Zn$^{2+}$ access, enabling more uniform interfacial reactions. Experiments and simulations show that AuMI homogenizes the interfacial electric field and current distribution, promotes more uniform Zn plating/stripping, and limits dendrite growth. As a result, this regulated interfacial reaction mode enables AuMI Zn symmetric cells to operate stably for 3000 h at 1 mA cm$^{-2}$/1 mAh cm$^{-2}$ and for 1100 h at 10 mA cm$^{-2}$/10 mAh cm$^{-2}$, while AuMI Zn||NVO (NaV$_3$O$_8$\cdot$1.5H$_2$O) full cells retain 80.8 % capacity after over 5000 cycles at 1 A g$^{-1}$. These findings highlight the importance of combining ultrathin architecture, lateral electron transport, and open Zn2+ access in artificial interphases for stable aqueous Zn metal anodes.

cond-mat.mtrl-sci

Synthesis of a High-Capacity α-Fe2O3@C Conversion Anode and a High-Voltage LiNi0.5Mn1.5O4 Spinel Cathode and Their Combination in a Li-Ion Battery

A Li-conversion alpha-Fe2O3@C nanocomposite anode and a high-voltage LiNi0.5Mn1.5O4 cathode are synthesized in parallel, characterized, and combined in a Li-ion battery. alpha-Fe2O3@C is prepared via annealing of maghemite iron oxide and sucrose under an argon atmosphere and subsequent oxidation in air. The nanocomposite exhibits a satisfactory electrochemical response in a lithium half-cell, delivering almost 900 mA h g-1, as well as a significantly longer cycle life and higher rate capability compared to the bare iron oxide precursor. The LiNi0.5Mn1.5O4 cathode, achieved using a modified co-precipitation approach, reveals a well-defined spinel structure without impurities, a sub-micrometrical morphology, and a reversible capacity of ca. 120 mA h g-1 in a lithium half-cell with an operating voltage of 4.8 V. Hence, a lithium-ion battery is assembled by coupling the alpha-Fe2O3@C anode with the LiNi0.5Mn1.5O4 cathode. This cell operates at about 3.2 V, delivering a stable capacity of 110 mA h g-1 (referred to the cathode mass) with a Coulombic efficiency exceeding 97%. Therefore, this cell is suggested as a promising energy storage system with expected low economic and environmental impacts.

physics.chem-ph