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

Abstract

The potential of germanium‐based anodes for sodium‐ion batteries (NIBs) is seriously hindered by the high diffusion barrier of Na ions in the Ge lattice. Herein, a massive and defect‐rich 2D germanene nanosheet based anode is fabricated and exhibits enhanced Na‐storage performance for NIBs. Unlike the typical alloying/dealloying reactions of crystalline Ge, the germanene nanosheets are converted to go through a pseudointercalation mechanism during charge/discharge processes. Accordingly, the diffusion energy barriers of sodium atoms in the germanene nanosheets are significantly reduced, leading to high Na‐storage activity. Combined with its large surface area, high mechanical flexibility, fast electron mobility as well as its defect‐rich structure, the germanene anode delivers an initial capacity of 695 mAh g−1, enhanced cycling performance, and outstanding rate capacities, compared with those of GeH nanosheets and Ge particles. It is believed that the germanene anode not only extends the scope of germanene application, but also provides new insights for adjusting Na‐storage pathways toward superior battery performance.

Zero‐Strain Structure for Efficient Potassium Storage: Nitrogen‐Enriched Carbon Dual‐Confinement CoP Composite

“…[1][2][3] In line with this, because of the abundant reserves of potassium resources, attractive price and the redox potential of K + /K (−2.93 V) comparable to that of Li + /Li (−3.04 V), potassium-ion batteries (PIBs) are expected to harvest fairly good output voltage and energy density with low cost. [4][5][6][7] Nevertheless, serious volume changes causing structural collapse, and sluggish reaction kinetics of electrodes during electrochemical cycling process are still remarkable challenges that need tremendous efforts to improve K + reaction kinetics and structural robustness targeting further to strengthen the potassium storage ability of electrode materials. [8][9][10][11][12] Among a variety of anode materials applicable for PIBs, including metal-based compounds (transition metal phosphides, selenides, sulfides, oxides, and so on), [13][14][15][16][17] alloy phase, [18,19] carbon materials, [20,21] organic materials, [22] etc.…”

State-of-the-art advancements of atomically thin two-dimensional photocatalysts for energy conversion

“…Motivated by the success of graphene, some representative materials emerged and have been also intensively studied, mainly including hexagonal boron nitride (hBN), 16 transition metal dichalcogenides, 17 layered transition oxides, 18 layered double hydroxides (LDHs), 19 black phosphorus (BP), 20 silicene, 21 and germanene. 22 These 2D materials show 2D-limited transport of electrons and phonons, thereby delivering lots of interesting phenomena.…”

The Multicomponent Synergistic Effect of Sandwich Structure Hierarchical Nanofibers for Enhanced Sodium Storage

“…The power law formula i = aν b is generally used to determine the capacitive contribution, where i and v represent the peak currents and scan rates, a is the constant, b can be obtained from the slope of log(i)-log(v) fitting lines. [48][49][50] When b = 0.5 represents a typical diffusion-controlled process, b = 1.0 means the capacitive storage behavior. [51][52][53] The fitting results of main redox peaks for CMZC-1 are shown in Figure 4b.…”