Zn₂GeO₄@C Core–Shell Nanorods as Highly Reversible Anode Materials for Lithium‐Ion Batteries

Abstract

We report the synthesis of Zn2GeO4 nanorods using a simple hydrothermal process. After the coating of a carbon layer by the thermal decomposition of acetylene gas, the Zn2GeO4@C core–shell nanorods were obtained. The as‐synthesized Zn2GeO4@C core–shell nanorods were used as anode materials of lithium‐ion batteries, which showed good cycling and rate performance. A highly reversible specific capacity of 718 mAh g−1 after 400 cycles was achieved at a current density of 400 mA g−1. The core–shell nanostructures and partially amorphous and porous nanostructures helped to alleviate the volume change and enhance the conductivity during the charge/discharge process, which may be responsible for the good performance.

Continuous Hydrothermal Synthesis of Metal Germanates (M2GeO4; M = Co, Mn, Zn) for High‐Capacity Negative Electrodes in Li‐Ion Batteries

“…At potentials below 0.3 V vs. Li/Li + , another peak arose as the result of the formation of Li x Ge alloy. [42,43] Upon delithiation, two peaks appeared, centred at ca. 0.5 and 1.1 V vs. Li/Li + .…”

“…They were previously been assigned to the delithiation of the Li x Ge alloy and the combined delithiation of the Li x Zn as well as the partial oxidation of Zn and Ge, respectively. [42,43] This means that the lithiation and delithiation mechanism could be broadly expected to be as follows (see Equations 4 to 8);…”

Carbon Free Nanostructured Plate like WS2 with Excellent Lithium Storage Properties

“…Lithium-ion batteries (LIBs) have been realized as a most potential electrochemical energy storage system (EES) to power the portable electronics and electric vehicles because of their high energy density and long cycle life with costeffectiveness. [1][2][3][4][5][6] In order to further improve the energy density of state-of-art LIBs, there is a need for searching electrode materials with higher specific capacities than the currently used commercial graphitic carbon based anode. [7][8][9] The commercial graphite anodes with the most famous two-dimensional and layered structured can only provide a theoretical specific capacity of 372 mA h g -1 .…”