Monolayer MXene Nanoelectromechanical Piezo‐Resonators with 0.2 Zeptogram Mass Resolution

2D materials‐based nanoelectromechanical resonant systems with high sensitivity can precisely trace quantities of ultra‐small mass molecules and therefore are broadly applied in biological analysis, chemical sensing, and physical detection. However, conventional optical and capacitive transconductance schemes struggle to measure high‐order mode resonant effectively, which is the scientific key to further achieving higher accuracy and lower noise. In the present study, the different vibrations of monolayer Ti(3)C(2)Tx MXene piezo‐resonators are investigated, and achieve a high‐order f(2,3) resonant mode with a ≈234.59 ± 0.05 MHz characteristic peak due to the special piezoelectrical structure of the Ti(3)C(2)Tx MXene layer. The effective measurements of signals have a low thermomechanical motion spectral density (9.66 ± 0.01 [Formula: see text]) and an extensive dynamic range (118.49 ± 0.42 dB) with sub‐zeptograms resolution (0.22 ± 0.01 zg) at 300 K temperature and 1 atm. Furthermore, the functional groups of the Ti(3)C(2)Tx MXene with unique adsorption properties enable a high working range ratio of ≈3100 and excellent repeatability. This Ti(3)C(2)Tx MXene device demonstrates encouraging performance advancements over other nano‐resonators and will lead the related engineering applications including high‐sensitivity mass detectors.