Design of Highly Positive Triboelectric Materials Via Controlling Local Dipole

Abstract

The design of positive triboelectric materials is highly required to realize high-performance triboelectric generators. Here, we establish a novel design protocol for highly positive triboelectric materials via the maximization of local dipole and suggest nitrogen-based dimethylol urea, diazolidinyl urea, and imidazolidinyl urea as promising positive triboelectric materials. The mechanism that nitrogen-based materials provide highly positive triboelectric properties is investigated using density functional theory calculation. Highly electronegative atoms (e.g. nitrogen and oxygen) attract electrons from neighboring atoms, resulting in the formation of negative local dipoles in the highest occupied molecular orbital consisting of non-bonding electrons, thereby forming an electron-donating environment. We confirmed the proposed design protocol by quantitatively investigating the triboelectric properties of nitrogen-based materials and analyzing the charge transfer characteristics based on local dipole interactions.