Si L, Wang J, Xu X. Reduced Graphene Oxide-Coated Separator to Activate Dead Potassium for Efficient Potassium Batteries.
MATERIALS (BASEL, SWITZERLAND) 2022;
15:5505. [PMID:
36013642 PMCID:
PMC9412676 DOI:
10.3390/ma15165505]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 08/01/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Potassium (K) metal batteries (KMBs) have the advantages of relatively low electric potential (-2.93 V), high specific capacity (687 mAh g-1), and low cost, which are highly appealing to manufacturers of portable electric products and vehicles. However, the large amounts of "dead K" caused by K dendrite growth and volumetric expansion can cause severe K metal anode deactivation. Here, a thin layer of conductive reduced graphene oxide (rGO) was coated on a GF separator (rGO@GF) to activate the generated dead K. Compared with the batteries adopting an original separator, those adopting a modified separator have significantly improved specific capacity and cycling stability. The life of full-cell of KMBs combining an rGO@GF separator with synthesized K0.51V2O5 is expected to exceed 400 cycles, with an initial capacity of 92 mAh g-1 at 0.5 A g-1 and an attenuation rate per cycle as low as 0.03%. Our work demonstrates that a composite separator of high conductivity is beneficial for high performance KMBs.
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