Dual Intermediates in C-C Coupling Reactions and High-Performance Sodium-Iodine Batteries: In Situ Generated Quasi-Graphene in Anthraquinone-Inserted Layered Double Hydroxide.

Abstract

Na-I₂ batteries are a cost-effective alternative to conventional energy storage technologies. However, their development is hindered by highly soluble polyiodides and sluggish redox kinetics. Herein, the issues are solved by a 1,8-dianthraquinone (AQ)-inserted layered double hydroxide (CoNi LDH-AQ) formulated as Co_1.65Ni_4.35(CO₃)_1.5(OH)₃(AQ)₃, whose interlayer channel not only immobilizes polyiodides but also acts as a confined vessel for the C-C couplings of AQ into functionalized quasi-graphene (F-GO). The in situ generated I⁺ not only promotes the I^-/I₂/I⁺ multielectron conversion to boost redox kinetics, eliminate shuttle effect, and achieve superior capacities/lifespans but also accelerates the couplings of AQ with low barriers. The work proposes a two-in-one strategy, which combines inorganic and organic reactions together with the same intermediate. It provides a routine to synthesize quasi-graphene based on the couplings of small organic species in a confined space to suppress aggregation. And the good conductivity of quasi-graphene in turn facilitates electron transfer in Na-I₂ batteries.