PNNL

Abstract

Alloy materials have been emerged to achieve compatible properties in various applications. The structural manipulation, however, requires sensitive and complicated synthetic process. Herein, we report atomic-scale combination of germanium-zinc distorted alloy exhibiting uncertain eutectic point in a phase diagram can imply a great potential to form atomically collaborated array via a simple fabrication method. When interconnected together, it prevents a fatal sublimation of germanium/germanium oxide during gas-solid phase reduction reaction and allows outstanding electronic conductivity as well as high available capacity in lithium-ion batteries, leading to structural and electrochemical evolution of germanium/zinc distorted array. Further, the unique features are clearly confirmed through in situ analysis. Besides, as-prepared battery anodes remarkably highlights outstanding rate capabilities (capacity retention of ~50% at 20 C compared to 0.2 C-rate) and cycle retention (73% at 3.0 C-rate) with a capacity of 546 mAh g-1 even after 1000 cycles. Even when assembled in a full cell, it notably facilitates considerable energy density during 400 cycles with 99.4% of average coulombic efficiency, which is suitable for a large-scale energy storage system.