Pressure Sensor For Applications Research Articles

A comprehensive compensation method for piezoresistive pressure sensor based on surface fitting and improved grey wolf algorithm

The optimized surface fitting method base on improved gray wolf algorithm (IGWO) is proposed to overcome the nonlinearity and temperature drift of piezoresistive pressure sensor. To improve the convergence rate and search ability of gray wolf optimization algorithm (GWO), the adjustable nonlinearity convergence factor is established. The weight vector and weight adjustment coefficient are integrated into the residual function of the least square method. Employing the maximum full range error as the fitness function, the least square method is continuously optimized by IGWO to establish the high-performance comprehensive compensation mathematical formula. The simulation and practical test results indicate that the maximum full-scale error in the full range is better than 0.03 %, and the maximum full-scale error in the local range is less than 0.02 % especially. The proposed method proposed method is very suitable for the application and production of industrial pressure sensor with many advantages.

Rapid and facile fabrication of hierarchically porous graphene aerogel for oil-water separation and piezoresistive sensing applications

Graphene aerogel (GA) holds great potentials for versatile applications, for example, oil-water separation and piezoresistive sensing. However, GA is generally prepared via time-consuming and complicated methods. Herein, a rapid and facile approach has been proposed to fabricate GA by a two-step reduction method, i.e., hydrothermal reduction by thiourea at a mild temperature of 95 °C for 30 min followed by microwave treatment for several seconds, c.a., 4–12 s. GA was partially reduced in the first step and self-assembled into a 3D scaffold which is much more receptive to microwaves and promotes the second complete reduction by microwave treatment. By tuning the microwaving time, the GA microwaved for 10 s, that is, MGA-10 exhibits hierarchically porous microstructure, ultra-low density, and super compressibility. MGA-10 can be used as a recyclable absorbent with high absorption capacities (223 ∼ 430 g/g) towards various oils and organic solvents. Meanwhile, the high sensitivity of the electric resistance to the compressive strain enables MGA-10 promising for pressure sensor applications. The MGA-10 sensor demonstrates high sensitivity (1.112 kPa−1 at a pressure range of 0 ∼ 0.3 kPa) and excellent stability (>3000 cycles). This fabrication route paves the way to efficiently prepare highly compressible graphene aerogels for versatile applications.

Smart Clothing with Built‐In Soft Sensing Network for Measuring Temporal and Spatial Distribution of Pressure under Impact Scenarios

AbstractNowadays, the need for protective devices at man–machine interfaces is increasing in the fields of traffic, sports, construction, and military, etc. Dynamic pressure sensing technology with wide measuring range, high sensitivity, softness, and fast response is crucial for evaluation and optimization of the personal protective equipment under impact scenarios. However, current sensors hardly possess all the aforesaid required characteristics. For the first time, this article reports the evaluation and application of an innovative soft pressure sensor with modulus of 2 MPa, maximum pressure of 8 MPa, and over 500‐Hz frequency. A theoretical model, taking strain rate into consideration, is established to characterize the dynamic sensing behavior. A sensing network in the form of smart clothing is developed and used in a sled crash test, which is a standard approach to evaluate the safety of automobiles in collisions. The pressure distribution over the dummy's surface during the crash is acquired in real‐time, and compared with numerical simulations. This study is important to the study of occupant injury and crashworthiness design for vehicles, and it will benefit the automotive industry. With the built‐in sensing network, the smart clothing has promising applications in the pressure mapping of 3D flexible man–machine interface under impact scenarios.

Rational designed microstructure pressure sensors with highly sensitive and wide detection range performance

• High sensitivity (26.55 kPa −1 ) and wide work range (0.9 Pa-140 kPa) pressure sensor was demonstrated. • Micro-nano hierarchical structure sponge surface with random uneven pattern. • PDMS sponge fabricated via mixed sacrifice template and electrostatic self-assembly methods. • The pressure sensor has great potential for healthcare and human-machine interfaces. Highly sensitive pressure sensors are often deployed in human-machine interaction area, touch screen and human motion detection. However, there are still great challenges to fabricating with high sensitivity pressure sensor with wide-range detection. Herein, we developed a new strategy to fabricate a highly sensitive pressure sensor using sandpaper and improve its detection range using a sacrificial template. It was the fthatirst time to combine microstructure processing with the sacrificial template method to fabricate pressure sensor. The microstructure of sandpaper endowed the sensor with high sensitivity, and the elastic substrate enhanced the sensor ability to resist high pressure without being damaged. The fabricated sensor device exhibits a superior sensitivity of 39.077 kPa −1 in the range from 50 kPa to 110 kPa with a broad linear response. Remarkably, high pressure ceiling (<160 kPa) ensures that the sponge could be applied in different practical conditions to monitor a range of subtle human motions including finger, wrist bending, and pulse. For applications, the sensor device can not only detect the foot stepping behavior (0.7 MPa) but also produce an obvious response to an extremely slight paper (9 mg, ∼0.9 Pa). The successful preparation of this micro-structured elastic sponge material provided new ideas for exploring its potential applications in pressure sensors and flexible wearable electronic devices.

Antimicrobial MXene-based conductive alginate hydrogels as flexible electronics

Flexible electronics have received considerable attention for their potential applications in wearable human health monitoring. Recently, conductive hydrogels have shown great potential in the application of flexible electronic devices. However, the restricted space of the 2D plane restricts the performance of MXene sensors, and conventional conductive hydrogels lack antibacterial properties, limiting their deep application in biomedical-related products. To overcome these limitations, we proposed an antibacterial and conductive MXene-SA-TSA-AM hydrogel through the radical polymerization of acrylamide in this work. Specifically, the coupling between sodium alginate (SA) and dimethyloctadecyl-(3-trimethoxysilylpropyl) ammonium chloride (TSA) brought about excellent antibacterial properties. MXene-SA-TSA-AM Hydrogels showed compelling swelling ratios (36–38 times), great mechanical properties (up to 1780 %), excellent self-healing ability (<10 min), and reproducible adhesion. During the pressure sensor applications, MXene-SA-TSA-AM hydrogels were demonstrated to accurately and rapidly monitor human physiological activities of finger bend and pulse with a rapid response (<0.2 s) and high stability (up to 5000 cycles). Furthermore, the MXene-SA-TSA-AM hydrogel exhibited excellent antibacterial properties, which can successfully inhibit Staphylococcus aureus and Escherichia coli with efficiency up to 99.6 % and 99.3 %, respectively. Finally, we anticipated that this novel antibacterial and conductive MXene-SA-TSA-AM hydrogel would further promote the deeper application of flexible electronics in biomedical-related products.

Measuring posture change to detect emotional conditions for workers: A scoping review.

The emotional management of workers can not only increase the efficiency of work, but also contribute to the improvement of the productivity of a company. This scoping review surveyed the literature to identify the relationship between postural expression and emotion during sedentary tasks. We searched relevant literature published up to December 1, 2019 using seven electronic databases (PubMed, CINAHL, Embase, Web of Science, PsycINFO, IEEE Xplore, and MEDLINE Complete). A total of 14 publications were included in this scoping review. It was found that the application of pressure sensor and camera-based measurement equipment was effective. Additionally, it was proposed to predict the emotional state of the worker by using forward and backward movements as the main variable as opposed to left and right movements. The information-based analysis technique was able to further increase the accuracy of workers' emotion prediction. The emotion prediction of workers based on sitting posture could be confirmed for certain movements, and the information-based technical method could further increase the accuracy of prediction. Expansion of information-based technical research will further increase the possibility of predicting the emotions of workers based on posture, and this will in turn promote safer and more efficient work performance.

Flexible multifunctional hard coatings based on chromium oxynitride for pressure-sensing applications

The present work reports on the development of piezoresistive chromium oxynitride (CrN1−xOx) thin films deposited on flexible polymeric substrates. The relationship between the reactive gas supply (composed of 15% O2 and 85% N2) and the electromechanical response was analyzed in CrN1−xOx thin films, produced by glancing angle deposition (GLAD) in a sputtering DC-reactive environment. GLAD was used to modify the normal columnar growth microstructure into an inclined (zigzaglike) architecture, allowing us to the tune of the mechanical and electrical responses of the films. The piezoresistive response was quantified by the gauge factor (GF), reaching values from 2.3±0.1 up to 32.4±0.4 as the reactive gas was increased. The highest values of the GF of the CrN1−xOx films were found in the samples with hardness values in the order of 15.5 GPa and elastic modulus close to 173 GPa. This work shows that the change of characteristics, such as microstructure and the zigzag architecture of the films, can be powerful tools to improve the sensibility by the GF of the CrN1−xOx films and turn Cr-based thin films into an interesting multifunctional system with protective and sensing capabilities.

Electric Conductivity Study of Porous Polyvinyl Alcohol/Graphene/Clay Aerogels: Effect of Compression.

In this work, poly(vinyl alcohol) (PVOH)/graphene (GN) oxide/clay aerogels were prepared using montmorillonite (MMT) and kaolinite (KLT) as fillers. This work paves the way for the development of aerogels filled with MMT or KLT with high conductivity. The mechanical properties of the polymer/clay aerogels are enhanced by incorporating GN into these systems. These composite materials have an enhanced thermal stability, and the combination of PVOH and GN leads to interconnected channels which favored the conductivity when a clay (MMT or KLT) is added to the mixed PVOH/GN matrix. However, after compressing the samples, the conductivities drastically decreased. These results show that the design of solid MMT/GN and KLT/GN composites as aerogels allows maximizing the space utilization of the electrode volume to achieve unhindered ion transport, which seems contrary to the general design principle of electrode materials where a suitable porous structure is desired, such as in our uncompressed samples. These findings also demonstrate the potential of these materials in electrodes, sensors, batteries, pressure-sensing applications, and supercapacitors.

Highly Stable Silver Nanowires/Biomaterial Transparent Electrodes for Flexible Electronics.

Flexible transparent electrodes (FTEs) possess excellent optoelectrical properties, mechanical robustness, and environmental adaptability are important for the industrial scale development of flexible electronics. Silver nanowires (AgNWs) are widely used in FTEs owing to their excellent optoelectrical properties and mechanical flexibility. However, the high surface roughness and poor stability of AgNWs FTEs still limit their practical applications. Here, highly stable FTEs are demonstrated via combining AgNWs and biomaterial propolis which is eco-friendly and antioxidative. The AgNWs/propolis composite transparent electrodes exhibit excellent optoelectrical performance as well as a smooth surface (root-mean-square roughness ∼ 6.2 nm). Meanwhile, the composite electrodes possess high mechanical stability (10,000 bending cycles), thermal stability, and environmental adaptability (60 °C and 85 ± 3% humidity for 700 h). The versatile composite FTEs show great potential applications in organic light-emitting diodes and pressure sensors, which exhibit high performance, mechanical stability, and environmental adaptability. Our strategy of introducing biocompatible materials into metallic nanowires opens up new possibilities to achieve high-quality FTEs in a simple and eco-friendly way.

Highly Sensitive Pressure Sensor Based on h-BN/Graphene/h-BN Heterojunction and Cu–Sn Solid–Liquid Interdiffusion Bonding

Graphene with atomic layer thickness has excellent mechanical properties and provides tremendous potential for developing high-performance pressure sensors. However, bare graphene is sensitive to humidity, and oxygen in the air also significantly affects the stability of graphene pressure sensor. In this work, a highly sensitive pressure sensor was fabricated through the MEMS process and nanofilm transferring. The graphene sensing element is entirely isolated from the external environment by the initial protection of h-BN, followed by the secondary protection of Cu–Sn solid–liquid interdiffusion bonding. After the static test, an average sensitivity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.9\times10$ </tex-math></inline-formula> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−4</sup> kPa <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> was achieved over a pressure range from −80 to 0 kPa. Also, it exhibited excellent repeatability and minimal hysteresis. As graphene pressure sensor was exposed to ambient air for 30 days, the relative resistance change was just 2.3%. The resistance of graphene pressure sensor can also keep stable even if the device was stored in a high-temperature or high-humidity environment. Thus, this work provides a promising approach for the practical application of high-performance graphene pressure sensors.

Graphene‐Based Composite Foams with Tunable Porosity for Ultra‐Sensitive Low‐Pressure Applications

AbstractComposite foam sensors presenting promising applications in pressure sensors require seamless integration of conductive additives, simplicity of manufacturing with minimum footprint, and consistent performance with optimum mechanical properties. Here, a resistive‐type foam sensor based on polyvinyl alcohol (PVA) containing high loading of water‐based graphene slurry (30 vol%) developed by in situ condensation is presented. The composite foam sensor exhibits an open‐cell structure with high electrical conductivity (13.3 × 10–2 S m−1), high sensitivity (S = 8.2 ± 0.7 for pressure &lt;1 kPa), and minimum response time (8 ms). The effect of processing on porosity and the corresponding disparity in the electromechanical performance of the foam sensors is witnessed. A systematic method to evaluate the mechanical properties of foam sensors as per foam standards is described. In addition to assessing the electromechanical properties, the graphene‐based foam sensor is calibrated for the first time. The calibration curve and accuracy of the foam sensor are correlated to their morphology. Synthesis and facile integration of graphene in composites, their mechanical, electromechanical characteristics, and calibration of sensors are demonstrated. Furthermore, it is shown that the sensors can empower human‐machine interface systems using a custom‐developed user interface.

Influence of MnO2 Nanoparticles Addition on Structural, Optical and Dielectric Characteristics of PVA/PVP for Pressure Sensors

Films of PVA/PVP/MnO2 nanostructures were fabricated for pressure sensors fields with lightweight, flexible and low cost compare with other sensors. The structure, dielectric and optical characteristics of PVA/PVP/MnO2 nanostructures have been studied. The results showed that the dielectric constant, dielectric loss and A.C electrical conductivity of PVA/PVP blend are enhanced with the increase in MnO2 NPs content. The dielectric constant and dielectric loss decrease while the A.C electrical conductivity increases with the increase in frequency. The optical characteristics of PVA/PVP/MnO2 nanostructures showed that the absorbance was rise with increasing of the MnO2 NPs content. The indirect energy gap of PVA/PVP blend was reduced with increase in MnO2 NPs content. The optical constants of blend are changed with the increase in MnO2 NPs content. The pressure sensor application results of PVA/PVP/MnO2 nanostructures showed that the electrical capacitance (Cp) increases with the rise in applied pressure.

Laser Induced Graphene/Silicon Carbide: Core–Shell Structure, Multifield Coupling Effects, and Pressure Sensor Applications

AbstractLatest advances have witnessed the laser scribing of various active materials from synthetic polymers to natural sources without masks, post‐treatment, or toxic substances. However, laser induced graphene (LIG) on renewable precursors usually requires flame‐retardant pretreatment and multistep pulsed or defocused irradiation. Laser scribing of silicon carbide (SiC) from polydimethylsiloxane (PDMS) is limited by its high transparency over a broad wavelength range. Here, a structural design strategy is adopted to solve these two dilemmas at the same time, that is, laser scribing of carbonized cloth/PDMS to prepare LIG/SiC composites. Natural cotton cloth is precarbonized and inserted in PDMS substrate to facilitate heat absorption for the in situ formation of SiC, while the soft PDMS attached to the carbonized cloth absorbs heat and isolates oxygen, enabling the conversion of amorphous carbon to LIG. Under these multifield coupling effects, a core–shell LIG/SiC electrode is formed on the carbonized cloth with tunable mass ratio, morphology, and graphene defects. Experimentally, the LIG/SiC pressure sensor exhibits a good sensitivity of 1.91 kPa−1 in the super‐wide sensing range of 0–226.7 kPa. By demonstrating different scenarios such as real‐time monitoring of large body movements, tiny pulses and heartbeats, the flexible pressure sensors hold great promise in wearable electronics.

Roles of MXene in Pressure Sensing: Preparation, Composite Structure Design, and Mechanism.

Flexible pressure sensors are one of the most important components in the fields of electronic skin (e-skin), robotics, and health monitoring. However, the application of pressure sensors in practice is still difficult and expensive due to the limited sensing properties and complex manufacturing process. The emergence of MXene, a red-hot member of the 2D nanomaterials, has brought a brand-new breakthrough for pressure sensing. Ti3 C2 Tx is the most popular studied MXene in the field of pressure sensing and shows good mechanical, electrical properties, excellent hydrophilicity, and extensive modifiability. It will ameliorate the properties of the sensitive layer and electrode layer of the pressure sensor, and further apply pressure sensing to many fields, such as e-skin flexibility. Herein, the preparation technologies, antioxidant methods, and properties of MXene are summarized. The design of MXene-based microstructures is introduced, including hydrogels, aerogels, foam, fabrics, and composite nanofibers. The mechanisms of MXene pressure sensors are further broached, including piezoresistive, capacitive, piezoelectric, triboelectric, and potentiometric transduction mechanism. Moreover, the integration of multiple devices is reviewed. Finally, the chance and challenge of pressure sensors improved by MXene smart materials in future e-skin and the Internet of Things are prospected.

Recognition of Cattle's Feeding Behaviors Using Noseband Pressure Sensor With Machine Learning.

Automatic monitoring of feeding behavior especially rumination and eating in cattle is important to keep track of animal health and growth condition and disease warnings. The noseband pressure sensor is not only able to accurately sense the pressure change of the cattle's jaw movements, which can directly reflect the cattle's chewing behavior, but also has strong resistance to interference. However, it is difficult to keep the same initial pressure while wearing the pressure sensor, and this will pose a challenge to process the feeding behavior data. This article proposed a machine learning approach aiming at eliminating the influence of initial pressure on the identification of rumination and eating behaviors. The method mainly used the local slope to obtain the local data variation and combined Fast Fourier Transform (FFT) to extract the frequency-domain features. Extreme Gradient Boosting Algorithm (XGB) was performed to classify the features of rumination and eating behaviors. Experimental results showed that the local slope in combination with frequency-domain features achieved an F1 score of 0.96, and recognition accuracy of 0.966 in both rumination and eating behaviors. Combined with the commonly used data processing algorithms and time-domain feature extraction method, the proposed approach improved the behavior recognition accuracy. This work will contribute to the standardized application and promotion of the noseband pressure sensors.

3D-printed endoplasmic reticulum rGO microstructure based self-powered triboelectric pressure sensor

Developing new generation of self-powered triboelectric sensors is urgent in the application of Internet of things (IoT) with low-power consumption. However, the traditional triboelectric pressure sensors demonstrate narrow detection range and are used to be less sensitive in large pressure range. In this work, a 3D-printed endoplasmic reticulum rGO microstructure based self-powered triboelectric pressure sensor (rGO-TPS) has been proposed. By employing PDMS@rGO framework as dielectric layer and spacer, a force-electric coupling model was built to investigate the electromechanical sensing mechanism. Owing to the ultra-low Young’s modulus of the 3D-printed materials and designed device structure, the rGO-TPS can reach the sensitivity of 6.28 kPa−1 and broaden high-sensitivity region from 0.65 Pa to 10 kPa. Besides, it also improves the sensitivity to 0.61 kPa−1 during the large pressure range from 10 kPa to 140 kPa. It also illustrates a fast response time of 92 ms and great stability of 3,000 cycles without fatigue. In addition, the dynamic pressure response can be monitored by detecting the change of pulse-like short-circuit current signal. Benefiting from the structural advantages and ultra-high performance, several potential applications in gauging water droplets and air flows, and vibration recognition have also been successfully demonstrated. This work provides a promising strategy to promote the progress toward the practical application of self-powered triboelectric pressure sensor.

A poling-free PVDF nanocomposite via mechanically directional stress field for self-powered pressure sensor application

It is well known that Poly(vinylidene fluoride) (PVDF) polymer and its composites exhibit limited piezoelectricity only after strong electric field poling (SEFP) to align randomly oriented molecular dipoles inside. Here, we report that a (Pb, Zr)TiO3 (PZT) particles doped PVDF-polymer nanocomposite shows a large poling-free piezoelectric (PFP) coefficient and strong electromechanical coupling after experiencing mechanically directional stress field (MDSF). Analyses based on WAXD, FTIR, and HRTEM reveal that the MDSF actives and then induces a crystal phase transformation (CPT) from disordered star-shape nanocrystals to ordered, self-poled chain-shape high-β nanocrystalline fibers. PFM scanning images further show the existence of well-defined polarization. Furthermore, a 7-layer series-connected, self-powered circular pressure sensor was fabricated using multi-material 3D-printing technology, which exhibits a high sensitivity of 235 mV/kPa and a high-power density of 0.9 mW/cm2 under a dynamic pressure of 255 kPa, and it is near 8 times higher than that of a conventional, poled single-layer PVDF sensor. Finally, a (3 × 3) real-time lighting tactile sensor array is 3D printed, confirming its feasibility for practical application. The MDSF-induced CPT and large PFP effect are significant because it may open a way to fabricate piezopolymer integrated devices without SEFP.

Siloxene/PVDF Composite Nanofibrous Membrane for High‐Performance Triboelectric Nanogenerator and Self‐Powered Static and Dynamic Pressure Sensing Applications

AbstractPolymer nanofibers are widely adopted in energy harvesting and pressure sensing applications owing to the large contact area and inherent compressibility. Herein, a high‐performance triboelectric nanogenerator (TENG) based on 2D siloxene‐polyvinylidene fluoride (S‐PVDF) composite nanofibrous membrane is newly evaluated. Through proper ratio optimization and facile electrospinning, the fabricated membrane shows significant improvement in dielectric property, electronegativity, and compressibility. The TENG comprising S‐PVDF membrane and Nylon 6/6 can deliver an excellent power density of 13.25 W m−2 (f ≈ 5 Hz) and easily operates low‐power electronics and Internet of things (IoTs). In addition, the excellent compressibility of membrane extends its applicability to self‐powered simultaneous detection of dynamic and static pressure, which is investigated by developing a hybrid pressure sensor (HPS) through effective integration of TENG and a capacitive pressure sensor. The HPS shows an excellent dynamic (12.062 V kPa−1 at (&lt;3 kPa) and 2.58 V kPa−1 at (3–25 kPa)) and static (25.07 mV kPa−1 at (&lt;3 kPa) and 5.96 mV kPa−1 at (3–25 kPa)) pressure sensitivities, respectively. Furthermore, a 2 × 2 HPS array tested and analyzed for multiple users using artificial intelligence significantly improves the accuracy (98%). Remarkable energy harvesting performance and greater accuracy of the HPS manifests better preferences for future self‐powered IoT and smart tactile‐based user authentication systems.

Lead-free PDMS/PPy based low-cost wearable piezoelectric nanogenerator for self-powered pulse pressure sensor application

Self-powered biocompatible electronic devices to detect vital physiological signals of the human body are in great demand in wearable applications. In this work, a low-cost polydimethylsiloxane/polypyrrole composite polymer film-based piezoelectric nanogenerator is fabricated and utilized as a self-powered arterial pulse pressure sensor. XRD and Raman analysis are used to confirm the crystal structural orientation and chemical composition of composite polymer, respectively. Uniform and crack-free morphology of PDMS/PPy composite polymer film is confirmed via Field Emission Scanning Electron Microscopy, while Energy Dispersive X-Ray is used to study the elemental analysis of composite polymer film, which confirms that there is no extra impurity present in the system. A flexible and robust piezoelectric nanogenerator with device configuration of Al coated PET/(PDMS: PPy)/ ITO coated PET is fabricated that gives an output voltage of 12 V and current density of 0.11 µA/cm2 when 1.47 N/cm2pressure is applied. The biocompatible nanogenerator as a self-powered pulse sensor is demonstrated, thus proving its potential for developing versatile self-powered systems useful in biomedical applications.

A Study on Graphene Structure Control Using Ammonia Gas for a Highly Sensitive Pressure Sensor

Graphene has been used in various fields because of its excellent mechanical, optical, electrical, and thermal properties. However, its intrinsic low sensitivity to pressure limits its sensor applications. To overcome this drawback, many researchers have tried to improve the sensitivity by controlling the defects on the graphene, but have yet to report a significant increase in sensitivity compared to the pristine graphene. Herein, we fabricated a graphene-based highly sensitive pressure sensor by flowing ammonia gas during chemical vapor deposition. The ammonia gas assisted the generation of nano-sized defects due to nitrogen doping in the graphene lattice, as well as macro-sized cracks in the graphene layer, due to the corrosion of the Cu surface. We regulated the concentration ratio of ammonia gas and methane gas during the graphene synthesis, which controlled the crack generation. These cracks weakened the in-plane force of the networks in the geometric structure of the graphene, thereby allowing them to deform more easily under external force, and changing the resistance of the sensor dramatically. As a result, the sensitivity of the pressure sensor increased about 10,000 times higher than that of the pristine graphene. These results suggest that controlling defects to improve graphene’s mechanical sensitivity provides a promising route to pressure sensor applications.