Synchronous Promotion in Sodiophilicity and Conductivity of Flexible Host via Vertical Graphene Cultivator for Longevous Sodium Metal Batteries

Abstract

Sodium (Na) metal batteries are nowadays appealing due to high specific capacity and low cost. However, major caveats including severe Na dendrite growth, unstable solid electrolyte interphase formation, and poor mechanical robustness have hampered its practicability. In this report, a highly sodiophilic and conductive host harnessing hierarchical vertical graphene (VG) cultivator and Co nanoparticle/N‐doped carbon decorator (Co‐VG/CC) is designed to accommodate Na metal throughout a facile infusion route. The strong interaction between Co‐VG/CC and Na is realized by sodiophilic Co nanoparticle/N‐doped carbon hybrid, resulting in excellent structural stability of the electrode. The well‐regulated Na adsorption behavior and uniform stripping/plating mechanism is systematically investigated via theoretical simulation in harmonization with in situ/ex situ electroanalytical analysis. In consequence, as‐derived Na@Co‐VG/CC electrode effectively inhibits the dendrite formation, resulting in promising electrochemical performances in symmetric cell configuration (functioning at an elevated rate of 5.0 mA cm−2 under 5.0 mAh cm−2 for 280 h, delivering a high capacity of 6.0 mAh cm−2 at 3.0 mA cm−2 for 1000 h and maintaining an ultralong lifespan up to 2000 h). Meanwhile, assembled flexible Na metal battery full cell can sustain to work for 120 h, representing a great advance in practical energy storage applications.

Synergizing Conformal Lithiophilic Granule and Dealloyed Porous Skeleton toward Pragmatic Li Metal Anodes

“…To gain deeper insight into the optimized Li nucleation behavior on D‐Cu@CuSe host, finite‐element method implemented by COMSOL Multiphysics was utilized to probe the local current density and Li‐ion concentration at the interface of anode/electrolyte (Figure S18, Supporting Information). [ 54–56 ] It is demonstrated in Figure a that the electric field presents a uniform distribution on the surface of D‐Cu@CuSe, which possibly benefits from the hexagonal CuSe plates. In terms of B‐Cu, current tends to aggregate toward a few tips, leading to an obvious intensity gradient (Figure 5b).…”

Design Principles of Sodium/Potassium Protection Layer for High‐Power High‐Energy Sodium/Potassium‐Metal Batteries in Carbonate Electrolytes: a Case Study of Na2Te/K2Te

“…Compared to traditional anode materials, the sodium‐ and potassium‐metal anodes possess high theoretical specific capacity (1165 and 687 mAh g −1 for Na and K, respectively), low redox potential (−2.71 (Na) and −2.93 V (K) vs standard hydrogen electrode), and abundant resources (2.8 wt% (Na) and 1.5 wt% (K) in the Earth's crust). [ 1–6 ] Additionally, the sodium‐ and potassium‐metal anodes can pair with high capacity cathodes to achieve high energy and power density, including Na/K‐O 2 , [ 7,8 ] Na/K‐CO 2 , [ 9,10 ] Na/K‐S, [ 11–13 ] and Na/K‐organic batteries. [ 14 ] Therefore, the sodium‐metal batteries (SMBs) and potassium‐metal batteries (PMBs) have been considered as the most promising potential candidates for low‐cost and large‐scale energy storage systems.…”

A 3D Hierarchical Host with Enhanced Sodiophilicity Enabling Anode‐Free Sodium‐Metal Batteries

“…Furthermore, the calculated cumulative areal capacity as a function of current density further demonstrates the superior performance and long-term stability of the PC-CFe symmetric cell compared to the previous SMA systems (Figure 3d). [30,31,34,38,[65][66][67] In order to evaluate the effect of the carbon coating on Fe NP on enhanced sodiophilicity, DFT calculations of the Na adsorption energy on Cu(111), graphene (Gr), and carbon-coated Fe NPs (CFe), which are representative model structures of Cu foil, PC, and PC-CFe, respectively, were performed. In addition to the pristine graphene surface (P-Gr), various point defects were also considered for Gr or CFe structures such as monovacancy (MV), divacancy (DV), trivacancy (TV), and Stone-Wales (SW) defects (Figure S18, Supporting Information).…”

“…Furthermore, the calculated cumulative areal capacity as a function of current density further demonstrates the superior performance and long‐term stability of the PC‐CFe symmetric cell compared to the previous SMA systems (Figure 3d). [ 30,31,34,38,65–67 ]…”