Unveiling the "Proton Lubricant" Chemistry in Aqueous Zinc-MoS2 Batteries

Angew Chem Int Ed Engl. 2022 Dec 12;61(50):e202211478. doi: 10.1002/anie.202211478. Epub 2022 Nov 16.

Abstract

Proton insertion chemistry in aqueous zinc-ion batteries (AZIBs) is becoming a research hotspot owing to its fast kinetics and additional capacities. However, H+ storage mechanism has not been deciphered in the popular MoS2 -based AZIBs. Herein, we innovatively prepared a MoS2 /poly(3,4-ethylenedioxythiophene) (MoS2 /PEDOT) hybrid, where the intercalated PEDOT not only increases the interlayer spacing (from 0.62 to 1.29 nm) and electronic conductivity of MoS2 , but also activates the proton insertion chemistry. Thus, highly efficient and reversible H+ /Zn2+ co-insertion/extraction behaviors are demonstrated for the first time in aqueous Zn-MoS2 batteries. More intriguingly, the co-inserted protons can act as lubricants to effectively shield the electrostatic interactions between MoS2 /PEDOT host and divalent Zn2+ , enabling the accelerated ion-diffusion kinetics and exceptional rate performance. This work proposes a new concept of "proton lubricant" driving Zn2+ transport and broadens the horizons of Zn-MoS2 batteries.

Keywords: Aqueous Zn-Ion Batteries; Cathode; DFT Computations; MoS2; Proton Lubricant.