Imaging the Self-Healing Dynamics of Single-Nanoparticle Electron Transfer Event Regulated by Local Electron Insertion

The self-healing properties of nanomaterials to resistelectronbeam damage are of great concern, which is inspiring to improve thestability and electron transfer efficiency of nanoelectronic devicesespecially in an abnormal environment. However, the influence of electronbeam insertion on the electron transfer efficiency of single nanoentitiesat a heterogeneous electrochemical interface is still in debate, whichis a concern for the development of in situ liquidcell transmission electron microscopy of the next generation. Herein,we employ an electro-optical imaging technique and directly visualizethe controllable recovery of electron transfer ability for singlePrussian blue nanoparticle (PBNP) after electron beam insertion withdifferent electron doses. While eliminating e-beam damage by decreasingcharge accumulation, the precise control of electron insertion behaviorsinduces a lossless chemical reduction mechanism for metal ions onthe framework structure of PBNP, which leads to static imbalance andtemporarily blocks the electron transfer channels. A subsequent chargerebalance process at a sub-nanoparticle level driven by electrochemicalcycling controllably rebuilds the ion migration channels on the outerlayer of single PBNP to repair the electron transfer path, which isconfirmed by single-nanoparticle spectral characterizations. Thiswork provides a generic methodology to study the electron-particleinterplay and mechanism of electrode materials for eliminating theheterogeneity of electrochemical activity down to a sub-nanoparticlelevel.

Automated summary

This study directly visualizes the controllable recovery of electron transfer ability for single Prussian blue nanoparticles (PBNPs) after electron beam insertion using an electro-optical imaging technique. By eliminating e-beam damage and precisely controlling electron insertion behaviors, a lossless chemical reduction mechanism for metal ions on the framework structure of PBNP is induced, temporarily blocking electron transfer channels. A subsequent charge rebalance process at a sub-nanoparticle level rebuilds ion migration channels on the outer layer of single PBNP, repairing the electron transfer path. This work provides a generic methodology to study the electron-particle interplay and mechanism of electrode materials at a sub-nanoparticle level.