A Robust Approach for Efficient Sodium Storage of GeS₂ Hybrid Anode by Electrochemically Driven Amorphization

Abstract

Sodium ion batteries (NIBs) have become attractive promising alternatives to lithium ion batteries in a broad field of future energy storage applications. The development of high‐performance anode materials has become an essential factor and a great challenge toward satisfying the requirements for NIBs, advancement. This work is the first report on GeS2 nanocomposites uniformly distributed on reduced graphene oxide (rGO) as promising anode materials for NIBs prepared via a facile hydrothermal synthesis and a unique carbo‐thermal annealing. The results show that the GeS2/rGO hybrid anode yields a high reversible specific capacity of 805 mA h g−1 beyond the theoretical capacity, an excellent rate capability of 616 mA h g−1 at 5 A g−1, and a cycle retention of 89.4% after 100 cycles. A combined ex situ characterization study reveals that the electrochemically driven amorphization plays a key role in achieving efficient sodium storage by accommodating excess sodium ions in the electrode materials. Understanding the sequential conversion‐alloying reaction mechanism for GeS2/rGO hybrid anodes provides a new approach for developing high‐performance energy storage applications.

Germanene Nanosheets: Achieving Superior Sodium‐Ion Storage via Pseudointercalation Reactions

“…As one of the most promising anode materials for rechargeable alkali ion batteries, germanium (Ge) has been widely studied in LIBs due to its excellent electrical conductivity and considerable storage capacity via the reversible alloying-dealloying reaction. [4][5][6][7][8][9] High retention of capacity and good rate capability have been reported for LIB anodes. Intuition based on experience suggests that Ge would also be suitable as an anode material for NIBs.…”

The novel two-dimensional photocatalyst SnN3with enhanced visible-light absorption for overall water splitting

“…Layered SnP3 is a new type 2D material predicted from GeP3 with ultrahigh carrier mobility (1.15×10 4 cmV -1 s -1 ) and great light absorption capacity [18][19][20][21][22]. Compared with other materials like GeS2 (0.52 Jm -2 ) [23,24], NaSnP (0.81 Jm -2 ) [25], GeP3 (0.91 Jm -2 ) [26], GaN2 (1.09 Jm -2 ) [27], InP3 (1.32 Jm -2 ) [13] and graphene (0.36 Jm -2 ) [28,29], the calculated cleavage energy of 1L and 2L SnP3 are 0.57 Jm -2 and 0.38 Jm -2 [20]. Therefore it is viable to exfoliate from the bulk.…”

Recent Progress in Rechargeable Sodium‐Ion Batteries: toward High‐Power Applications

“…The diffusion coefficient of sodium in germanium was estimated to be ≈10 −13 cm 2 s −1 . When tested as anode in half‐cell, a capacity of 164 mAh g −1 was obtained at charge/discharge rates up to 10 A g −1 (Figure b) . Despite promising electrochemical result has been achieved in some reports, the sophisticated synthesis process and intrinsic sluggish kinetics remain the major obstacles for making Ge anode competitively useful in high power SIBs.…”