Investigation of Contact Electrification between 2D MXenes and MoS₂ through Density Functional Theory and Triboelectric Probes

Abstract

Contact electrification (triboelectrification) (CE) is a universal phenomenon in ambient environment and has been recorded for more than 2600 years. Nonetheless, the intrinsic mechanism of CE still remains controversial. Herein, based on first-principles theory, the underlying mechanism in CE is systematically investigated between metallic MXenes and semiconductive MoS 2 . The results show that the work functions of contacting materials dominate the direction of electron transfer during CE process. That is, the electron will be transferred from the material with low work function to the one with high work function. The theoretical prediction is verified experimentally through investigating triboelectric probes based on MXenes and MoS 2 nanomaterials. Additionally, it is noted that the interfacial potential barrier and the work function difference together modulate the amount of transferred electron. Electron transfer mainly occurs in the repulsive forces region where the interaction distance between the two materials is shorter than the normal bonding length. The quantum calculation results agree well with the Wang transition theory. Furthermore, it is also noticed that, due to the wave-particle duality of electron, electron transfer will obviously occur at the attractive force region when the two contacting materials exhibit a larger work function difference.

Exploring Water/Ion Transport through the Polarized Lamellar Channels

“…29 Additionally, atomic charges calculated by theoretical methods, such as DFT, have a large discrepancy. 25,28,29,39,40 It is generally explained by the absence of a clear distinction of the electron density between atoms. 41 The partial charge values of the h-BN membrane used in the previous literature range from 0 to 1.05 e. 25,29,40,42,43 Generally, the partial charge on N and B atoms determined by DFT calculation is about ±0.4 e without water, and ±1.0 e in water.…”

Triboelectric Nanogenerator Based on Copper Foam with Graded Porous Architectures for Energy Harvesting and Human Motion Monitoring

“…Recently, many researchers have investigated TENGs in an attempt to boost the triboelectric performance based on various strategies. , Surface or inner surface structure construction and modification is taken into consideration as one of the appropriate solutions to enhance the output performance and converting efficiency. Many fabrication methods have been used to achieve the complicated or patterned surface structures on triboelectric layers. − Photoetching and the related compound technology based on photoetching are the commonly used fabrication methods to build the functional structures .…”

Self‐Powered Intelligent Damper Integrated Triboelectric‐Electromagnetic Hybrid Unit for Vibration In Situ Monitoring of Stay Cables

“…The triboelectric nanogenerator (TENG) converts mechanical energy into electrical energy output based on the combination of triboelectric [7] and electrostatic induction, [8][9][10][11] which was first proposed by Wang's group in 2012. [12] The output signals transmitted by the TENG show outstanding performance in detecting mechanical changes [13] such as rotation, [14][15][16] vibration, [17][18][19][20] displacement, [21][22][23] and multifunctional motion.…”