Probing enhanced lithium-ion transport kinetics in 2d holey nanoarchitectured electrodes

Nanostructuring has been proved effective towards improving many energy storage and conversion devices, and is feasible for a wide range of materials. In particular, secondary nanoarchitectured materials exhibit collective advantages compared with nano-sized primary building blocks. Despite the manifold efforts in designed nanoarchitectures and synthetic routes, the underlying ion diffusion kinetics and phase transformation behaviors within nanoarchitectures still remain less explored. Herein, we probed enhanced lithium-ion transport behaviors using 2D holey zinc ferrite (ZFO) nanosheets as a model material, to demonstrate how self-assembled 2D holey nanoarchitectured electrodes can feature efficient ion diffusion channels, robust yet continuous electron transfer framework, and enlarged surface area, contributing to the superior performance over the ZFO nanoparticles without secondary structures. By revealing kinetic parameters through combined spectroscopic measurements and electrochemical techniques, our study manifests increased lithium-ion diffusion coefficients, higher capacitive charge storage contribution and reduced charge transfer impedance in holey nanosheets compared to randomly aggregated nanoparticles. Our results promote deeper understanding of significantly enhanced electrochemical energy storage properties of these 2D holey nanoarchitectured electrodes resulted from more uniform and complete phase transformation and better active material utilization.