Electrospun conductive carbon nanofiber hosts for stable zinc metal anode

Abstract

Summary Rechargeable zinc metal batteries (RZMBs) are emerging as promising candidates to replace lithium‐ion batteries due to their low cost, safety, and stability under ambient atmosphere. As the conductive substrates lower the actual current density, it is considered a chemical strategy to resolve the dendrite issue of RZMB. Herein, we propose to use the carbon nanofiber as a conductive substrate for the anode of RZMBs, which was prepared via heat treatment of electrospun PAN‐derived nanofiber. Through CV and SEM results performed at a constant current rate of 20 mA cm−2, the optimum amount of zinc deposited on the CNF was determined to be 10 mAh cm−2. Symmetric cell test for 400 hours showed 60.1% reduction in plating/stripping overpotential when zinc deposited carbon nanofiber was used. This overpotential reduction was attributed to the macroporous structure of ZnCNF and the preferred orientation of zinc to the (002) plane as confirmed by post mortem analyses. RZMB full cells pairing ZnCNF with β‐MnO2 were configured to deliver the 5C‐rate capacity of 106.54 mAh g−1, which was higher 34.13 mAh g−1 with bare zinc. Finally, the long‐term cyclability of ZnCNF|| MnO2 with much lower N/P ratio of 18.0 was confirmed, demonstrating the capacity retention of 89.4%, greater than 73% of bare zinc||MnO2 cell with the N/P ratio of 234.6 over 300 cycles.

Stable Sn@Cu foam enables long cycling life of zinc metal anode for aqueous zinc batteries

“…[13][14][15][16][17] To date, various measures have been taken to tackle these problems, including constructing artificial solid elctrolyte interphase (SEI) layers, [18][19][20][21] optimizing electrolyte components, [22][23][24][25] ZnX alloying (X = Sb, Ag, Cu) , [26][27][28] and designing substrate structure. [29][30][31] Of these, constructing three-dimensional (3D) conductive frameworks [32][33][34][35][36][37][38] which have excellent electrical conductivity, high surface area, relative structural rigidity, chemical inertness, and high porosity, is a highly effective strategy. It can not only reduce charge/mass transfer resistance and provide stable electric field distribution, 35 but also overcome volume variation of Zn deposits.…”

Bio‐Inspired Polyanionic Electrolytes for Highly Stable Zinc‐Ion Batteries

“…To quantify the intensity difference, Harris' method was applied by normalising the intensity of a particular plane to the sum of the rest intensities regarding the standard of JCDPS 04-0831. [24] As displayed in Table S1, the intensity ratio of (002) for SAcoated Zn is 0.795 compared to 0.555 for pristine Zn further confirming the domination of the parallel plating. This is consistent with the results from the TEM images after cycling that illustrate before.…”

Design Strategies toward High‐Utilization Zinc Anodes for Practical Zinc‐Metal Batteries

“…On the contrary, 3D carbon frameworks offer advantages such as low cost, stable electrochemical and mechanical performance, and the ability to undergo various chemical modifications, which can replace metal foams as conductive substrates for Zn anodes. Baek et al [49] developed a conductive substrate for the Zn anode by depositing Zn on carbon nanofibers (ZnCNF). The CNF was prepared via heat treating electrospun polyacrylonitrile (PAN) nanofibers (Figure 6b).…”