Mechano-Triboelectric Analysis of Surface Charge Generation on Replica-Molded Elastomeric Nanodomes

Abstract

Replica molding-based triboelectrification has emerged as a new and facile technique to generate nanopatterned tribocharge on elastomer surfaces. The “mechano-triboelectric charging model” has been developed to explain the mechanism of the charge formation and patterning process. However, this model has not been validated to cover the full variety of nanotexture shapes. Moreover, the experimental estimation of the tribocharge’s surface density is still challenging due to the thick and insulating nature of the elastomeric substrate. In this work, we perform experiments in combination with numerical analysis to complete the mechano-triboelectrification charging model. By utilizing Kelvin probe force microscopy (KPFM) and finite element analysis, we reveal that the mechano-triboelectric charging model works for replica molding of both recessed and protruding nanotextures. In addition, by combining KPFM with numerical electrostatic modeling, we improve the accuracy of the surface charge density estimation and cross-calibrate the result against that of electrostatic force microscopy. Overall, the regions which underwent strong interfacial friction during the replica molding exhibited high surface potential and charge density, while those suffering from weak interfacial friction exhibited low values on both. These multi-physical approaches provide useful and important tools for comprehensive analysis of triboelectrification and generation of nanopatterned tribocharge. The results will widen our fundamental understanding of nanoscale triboelectricity and advance the nanopatterned charge generation process for future applications.

Curvature-Adjustable Polymeric Nanolens Fabrication Using UV-Controlled Nanoimprint Lithography

“…The overall behavior of NOA73 predicted from the computational model agrees well with physical intuition. Future work includes refinement of the computational model with higher-order viscoelasticity, nonlinear properties of PDMS, and incorporation of air trapping and compression on the theory side and hybridization with replica moldinginduced triboelectric charge [16,[24][25][26] on the experimental side. different contact time periods: 1, 5, and 40 min.…”

Analytical Investigation of Replica-Molding-Enabled Nanopatterned Tribocharging Process on Soft-Material Surfaces

“…It is important to note the significance of this paper and its novelty compared to the prior works of the authors [ 3 , 4 , 5 , 18 ]. The previous works systematically document the experimental results, how to fabricate such intriguing nanoscale formations, and the summary of their behaviors from optical, electrical, and functional points of view.…”

“…To find the physical mechanism of the nanopatterned tribocharge formation, we established theoretical models based on computational mechanics [ 3 , 4 , 18 ] and transparent machine learning [ 19 ]. The former revealed that the level of the nanoscale tribocharging depends strongly on the surface-tangential and surface-normal stresses experienced by the PDMS surface during the demolding step of the replica-molding process ( Figure 1 a).…”

Quantifying nanoscale charge density features of contact-charged surfaces with an FEM/KPFM-hybrid approach

“…Analytical approaches to convert voltage to charge have relied on aggressive simplifications, e.g., approximating the entire micron-scale AFM probe/cantilever by a nanoscale sphere [9,11]. In other cases, charge has been estimated with brute force numerics, e.g., discretizing the surface into point charges and adjusting their values until the KPFM voltage at one single location is reached [8,19].…”