Flexible piezoresistive pressure sensors may exhibit excellent sensing performances to be applied in wearable electronics, medical diagnosis, and electronic skin. Herein, we report a multi-layer and phased-responsive reduced graphene oxide/MXene-based piezoresistive pressure sensor with hierarchical microspines constructed by sandpaper as the template. Thanks to the multi-level and multi-layer structure, the obtained sensor realized phased response and showed wide detection range (up to 70 kPa), fast response (response/recovery time of 40/80 ms), and excellent working stability (1000 fatigue cycles). Furthermore, the sensor was successfully applied for detecting various human motions including pulse beats, cheek bulging, nodding, finger bending, speech recognition, handwriting, and other pressure signals.Besides, a 6 × 6 sensing matrix integrated by the sensors was able to sensitively perceive the distribution of plane pressure. The findings in this work conceivably stand out as a new strategy to fabricate high-performance piezoresistive pressure sensors in the fields of intelligent healthcare and medical diagnosis, wearable electronic devices, electronic skin, and human−machine interaction.

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With the increasing deterioration of environmental and ecology caused by industrial wastewater pollution and petroleum spill accidents, superhydrophobic materials for oil–water separation have attracted considerable attention. Herein, we propose a facile approach to fabricate fluorine‐free superhydrophobic cotton fabric (CF) for oil–water separation after the coverage of chitosan (CS) and titanium dioxide (TiO2) nanoparticles and the subsequent hydrophobization modification by hexadecyltrimethoxysilane (HDTMS). The obtained HDTMS‐TiO2/CS@CF showed superhydrophobicity with a high water contact angle of 160.6° as well as excellent self‐cleaning capability, non‐adhesion capability and surface stability. Moreover, the CF was successfully applied for the separation of various oil–water mixtures. The separation efficiency for trichloromethane‐water mixture reached 95.8%, and still maintained 95.6% after 30 separation cycles. In addition, the CF also possessed superior photocatalytic degradation capability for organic contaminant such as oil red O and the degradation rate was 86.2% under UV irradiation for 180 min. The preparation method in this work is simple, environmentally friendly, low‐cost, and easy to produce on a large scale. The findings conceivably stand out as a new method to fabricate superhydrophobic materials and show great application potential in the fields of oil–water separation and water purification.