Thermally Stable Cellulose-Based Triboelectric Nanogenerators with Ultrahigh Charge Density Enabled by Deep Traps and Multiple Noncovalent Interactions

Abstract

Stable high-output for triboelectric nanogenerators (TENGs) in extreme environments is challenged by high charge dissipation rates and friction layer degradation at high temperatures. This study introduces a triboelectric material design that ensures stable high-output at high temperatures through a synergistic approach of multilayer noncovalent bonding and increased surface deep trap density. By grafting sulfonic acid groups onto cellulose and incorporating self-assembled molecules with large energy gaps, we significantly enhance the dielectric’s charge storage capacity and reduce charge dissipation by 82%. The modified cellulose exhibits a notable increase in deep trap density and improved mechanical properties through enhanced high-enthalpy states from noncovalent interactions. As a result, TENGs achieve an ultrahigh surface charge density of 152 μC/m² at 250 °C. This strategy presents a simple method for constructing TENGs with stabilized electrical output in high-temperature settings, facilitating their use as self-powered sensors in extreme conditions.