Binary sulfuric effect on ZnO laminated carbon nanofibers hybrid structure for ultrafast lithium storage capability

Abstract

The hybrid structure of high conductive carbon materials with large capacitive metal compounds is one of promising strategies for achieving high specific capacity, cycling stability, and ultrafast Li-ion storage capability due to their synergistic effects. This article will demonstrate the novel hybrid structure of a zinc oxysulfide (ZnOS) lamination layer on a sulfur (S)-doped carbon nanofiber (SCNF) matrix via an electrospinning method with sequential atomic layer deposition (ALD) process and will also present the structural advantages for ultrafast Li-ion batteries (LIBs). As a double-anion material, ZnOS has benefits compared with single ZnO and ZnS during the charge/discharge process, which is accompanied with consecutive conversion and alloying reactions. To verify these factors, structural analysis at the atomic scale and various electrochemical properties were evaluated. The resultant ZnOS/SCNF electrode showed superior electrochemical performance such as high specific capacity (672.8 mAh g−1 at 100 mA g−1), good capacity retention (87.8% after 100 cycles), and excellent cycling stability (85.4% after 500 cycles). This is attributed to the facilitated kinetic properties including electron and ion transfer efficiency during the electrochemical reactions, accompanied with the ZnOS/SCNF hybrid structure. In this regards, we believe that the ZnOS/SCNF electrode could be a great reference as a promising research strategy for accomplishing ultrafast LIBs.