Water-Mediated Spontaneously Dynamic Oxygen Migration on Graphene Oxide with Structural Adaptivity for Biomolecule Adsorption**Supported by the National Natural Science Foundation of China (Grant Nos. 11675138, 11705160, 11605151, U1832150, U1932123 and 11974366), the National Science Fund for Outstanding Young Scholars (Grant No. 11722548), the Key Research Program of Chinese Academy of Sciences (Grant No. QYZDJ-SSW-SLH053), the Fundamental Research Funds for the

Abstract

We theoretically and experimentally show that, with water being adsorbed, the graphene oxide (GO) is converted to a spontaneously dynamic covalent material under ambient conditions, where the dominated epoxy and hydroxyl groups are mediated by water molecules to spontaneously break/reform their C–O bonds to achieve dynamic oxygen migration. This dynamic material presents structural adaptivity for response to biomolecule adsorption. Both density functional theory calculations and ab initio molecular dynamics simulations demonstrate that this spontaneously dynamic characteristics is attributed to the adsorption of water molecules, which sharply reduces the barriers of these oxygen migration reactions on GO to the level less than or comparable to the hydrogen bonding energy in liquid water.