Oxidation-resistant vitamin C/MXene foam via surface hydrogen bonding for stable electromagnetic interference shielding in air ambient

MXenes have been the spotlight of interest as electromagnetic (EM) functional materials. However, the susceptibility (e.g., easy oxidation and fast decomposition) of MXenes leads to the fast fading of EM interference shielding effectiveness (EMI SE), which can be attributed to the easy degredation of MXene by reaction with water and oxygen in air. In this work, a series ofoxidation-resistant vitamin C/Ti₃C₂T_X foam composites were developed as an EMI shielding material. The vitamin C/Ti₃C₂T_X foam composites exhibited improved EM SE stability due to the protection of vitamin C by donating electrons. After exposing to air for 10 days, the EMI SE of vitamin C/Ti₃C₂T_X foam decreased slightly from 42.5 dB to 41 dB while the EMI SE of Ti₃C₂T_X foam dropped significantly from 47 dB to 35 dB. The EMI SE of vitamin C/Ti₃C₂T_X foam and Ti₃C₂T_X foam decreased correspondingly with further increase of exposuring time in air. However, the decreasing rate of vitamin C/Ti₃C₂T_X foam is always slower than that of the Ti₃C₂T_X foam. This work offers an effective way for the designing of oxidation-resistant MXene-based EMI shielding materials.