Seminar | MXenes from Atomic Motion to Intelligent Sensing: Diffusion, Mechanics, and Functional Interfaces

Chenglin Wu, associate professor in the Zachry Department of Civil and Environmental Engineering at Texas A&M University, will discuss research exploring the fundamental mechanics and atomic behavior of MXenes, a class of two-dimensional materials with applications in advanced sensing technologies. The seminar will examine how atomic diffusion, defects, fracture and interfacial behavior influence MXene performance, as well as how these properties can be leveraged to develop flexible biosensors and tactile sensors for applications in robotics, human-machine interaction and wearable technologies.

Abstract

Two-dimensional transition-metal carbides and nitrides, known as MXenes, combine atomic-scale structural tunability, high electrical conductivity, mechanical flexibility, and chemically active surfaces. This seminar presents our research through two interconnected tracks that link the fundamental behavior of MXenes to their development as functional materials for biosensing and tactile sensing.

The first track focuses on atomic diffusion and mechanics in MXenes. Using in situ electron microscopy, nanoscale mechanical testing, and multiscale modeling, we investigate surface-mediated diffusion, defect migration, interlayer interactions, and temperature-dependent structural evolution. These atomic processes govern deformation, fracture, friction, interface fusion, and self-healing in MXene sheets. Particular attention will be given to how composition, defects, and surface terminations regulate crack propagation, bending rigidity, energy dissipation, and the mechanical reliability of MXene-based interfaces.

The second track explores how these fundamental properties can be translated into biointegrated and mechanically responsive sensing platforms. By integrating MXenes with graphene, hydrogels, polymers, and molecular recognition elements, we develop flexible sensors for detecting biological targets, including viruses, bacteria, genomic DNA, and inflammation biomarkers. We will discuss how hydrogel gating, selective molecular transport, interfacial adhesion, and field-effect transistor architectures can improve sensitivity and selectivity under complex physiological conditions. In parallel, MXene-based tactile sensors are designed to detect pressure, contact, deformation, and interfacial delamination for applications in robotic perception, human–machine interaction, and wearable systems. Their performance depends not only on electrical conductivity but also on the mechanics of contact, load transfer, deformation, and material interfaces.

Together, these two tracks establish a mechanics-informed materials-to-systems framework in which atomic motion, fracture, and interfacial behavior guide the design of reliable MXene-based biosensors and tactile sensing technologies.