Flexible pressure sensors have aroused tremendous attention, owing to their broad applications in healthcare, robotics, and prosthetics. So far, it remains a critical challenge to develop low-cost and controllable microstructures for flexible pressure sensors. Herein, a high-sensitivity and low-cost flexible piezoresistive sensor was developed by combining a controllable graphene-nanowalls (GNWs) wrinkle and a polydimethylsiloxane (PDMS) elastomer. For the GNWs–PDMS bilayer, the vertically grown GNWs film can effectively improve the interface strength and form delamination-free conformal wrinkles. More importantly, a controllable microstructure can be easily tuned through the thermal wrinkling method. The wrinkled graphene-nanowalls (WG) piezoresistive sensor has a high sensitivity (S = 59.0 kPa–1 for the 0–2 kPa region and S = 4.8 kPa–1 for the 2–20 kPa region), a fast response speed (<6.9 ms), and a low limit of detection (LOD) of 2 mg (∼0.2 Pa). The finite element method was used to analyze the working mechanism of the sensor, which revealed that the periods of the wrinkles play a dominant role in the performances of the sensors. These prominent merits enable wrinkled graphene sensors to successfully detect various signals from a weak stimulus to large pressures, for example, the detection of weak gas and plantar pressure. Furthermore, object manipulation, tactile imaging, and braille recognition applications have been demonstrated, showing their great potential in prosthetics limbs and intelligent robotics.

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Flexible pressure sensors have received extensive attention in recent years due to their great importance in intelligent electronic devices. In order to improve the sensing performance of flexible pressure sensors, researchers are committed to making improvements in device materials, force-sensitive interfaces, and device structures. This paper focuses on the force-sensitive interface engineering of the device, which listing the main preparation methods of various force-sensitive interface microstructures and describing their respective advantages and disadvantages from the working mechanisms and practical applications of the flexible pressure sensor. What is more, the device structures of the flexible pressure sensor are investigated with the regular and irregular force-sensitive interface and accordingly the influences of different device structures on the performance are discussed. Finally, we not only summarize diverse practical applications of the existing flexible pressure sensors controlled by the force-sensitive interface but also briefly discuss some existing problems and future prospects of how to improve the device performance through the adjustment of the force-sensitive interface.