Abstract High-performance temperature sensors are critical components for emerging Internet-of-Things and biomedical-electronics platforms. However, simultaneously achieving high sensitivity, mechanical compliance, and user-defined integrability remains a formidable materials-and-device challenge. Here, we report a continuous graphene fiber (GF) thermocouple technology where multiple p–n thermocouples are created in situ along a single, unbroken fiber while preserving its structural integrity. By periodically modulating surface charge-transfer doping with polyethyleneimine (PEI) and FeCl 3 , we formed an array of ten p–n pairs that delivered an exceptional thermocouple sensitivity of 452.32 µV K −1 . The device retained ~97.8% of its initial sensitivity after 10,000 bending cycles at a 5-mm radius, confirming robustness under repeated mechanical deformation. When deployed on skin, the sensor tracked dynamic body temperature variations with a measurement error of 0.64%, validating its practical value for real-time, non-invasive health monitoring. These results establish all-carbon GF thermocouples as a high-precision and mechanically adaptable temperature-sensing platform for next-generation wearable electronics and personalized healthcare systems.

Real-time lactate monitoring is essential for clinical diagnostics, sports physiology, and industrial bioprocessing, yet conventional enzymatic sensors suffer from limited stability, narrow operational temperature range, and complex fabrication protocols. Herein, we report a robust non-enzymatic electrochemical sensor based on graphene fibers (GFs), featuring a GF/Au/Ni(OH)2 composite electrode with controllable structure fabricated via sequential electrodeposition. Systematic optimization of deposition parameters established a quantitative relationship between surface architecture and electrochemical response, revealing a critical trade-off between active site density and charge transport efficiency. The sensor achieved optimal performance when both Au and Ni(OH)2 were deposited for 900 s, exhibiting a high sensitivity of 1.24 mA mM−1 cm−2 and a remarkably broad operational temperature range of 0–100 °C. Moreover, the sensor demonstrates excellent repeatability, superior anti-interference capability against common electroactive species, and outstanding long-term durability with 97.8% response retention after 14 days. This work provides a rational design strategy for balancing catalytic activity and transport properties in metal–metal oxide composites, offering a reliable platform for advanced applications in next-generation wearable health-monitoring systems.

Textile electronics with extraordinary sensing capabilities holds significant potential in the Artificial Intelligence of Things (AIoT). However, little effort is paid to their mutual advantages of robust interfacial interactions, ultra-strong mechanical performance, and stability. Herein, we fabricate homogeneous and multifunctional core–shell macrofibers by integrating bridge-functionalized MXene/PEDOT:PSS conductive ink with aligned bacterial cellulose (BC). These resulting macrofibers feature mechanical properties (tensile strength of 433.2 MPa and the Young’s modulus of 25.9 GPa), exceptional electrical conductivity (10.05 S cm−1) and durable hydrophobicity. Such superior robustness allows for the fabrication of the macrofibers woven into textile-based triboelectric nanogenerator (PKT-TENG) and shows an impressive high-performance of a maximum open-circuit voltage of 272.54 V, short-circuit current of 14.56 μA and power density of 86.29 mW m−2, which successfully powers commercial electronics. As the proof-of-concept illustration, the macrofibers with durable hydrophobicity and high piezoresistive sensitivity are further employed for precepting diverse liquids that can simultaneously monitor their distinctive motion features via real-time resistance variation on the textile-based array. This work is expected to offer new insights into the design of advanced fibers with ultra-strong mechanical capabilities and high conductivity and provide an avenue for the development of textile electronics for high-performance sensing and intelligent manufacturing.

The advancement of high temperature resistant thin film strain sensors is crucial for detecting surface strain changes in aerospace turbine engines and launch vehicles. However, the strain sensitivity under high temperature thin film strain gauges is generally low, resulting in minimal resistance change under unit strain. In this regard, we proposed a thin film (thickness:similar to 500 nm) strain sensor, consisting of a composite structure including indium tin oxide with unconventional ratio (5-5 ITO, In2O3:SnO2 = 50:50 wt%) and Pt. Surprisingly, the strain sensor demonstrates ultrahigh sensitivity (gauge factor (GF) > 120, maximal GF = 178), rapid response time (0.12 s), as well as long cycling durability (10 h) under an operating temperature of 500 degrees C. The outstanding dynamic strain response and long-term temperature cycling stability of sensor originate from the micro-cracks in the sensitive film. The 5-5 ITO thin film produces island-like gaps with stress concentration in high-temperature environments, leading to a significant increase in resistance. Meanwhile, the top layer Pt structure covers the 5-5 ITO film, which aids in better recovery of micro-cracks, enhancing sensor repeatability and cycle durability. With its rapid response time, high sensitivity, and consistent performance at high temperatures, our strategy for this sensor holds great promise for applications in monitoring under extreme environment conditions.

One-dimensional nano-grating standard (ODNGS) is widely recognized as a crucial nanometric standard for metrological technology. However, achieving the ultratiny size of ODNGS with high consistent uniformity and low roughness by conventional processes such as the inductively coupled plasma (ICP) etching method presents a significant challenge in obtaining accurate calibration values. In this work, a 50-nm ODNGS with a conformal buffer layer (Al2O3) is successfully obtained, indicating outstanding stability and abrasion resistance. Remarkably, the introduction of hydrogen silsesquioxane (HSQ) and amorphous Al2O3 simultaneously guarantees an incredibly small expanded uncertainty (0.5 nm) and repeatability of the standard uniformity (less than 0.3 nm) in the grating dimensions. The I-V curves of ODNGS with an Al2O3 buffer layer at room temperature (RT) and 200 °C are depicted respectively to showcase the sustained favorable insulation properties. Notably, the nanostructure fluctuation, line edge roughness (LER) and line width roughness (LWR) of the standard can be decreased obviously by 64.1

Intelligent mechanical sealing is crucial for the advancement of equipment intelligence and the Internet of Things (IoT), as it effectively addresses significant challenges such as the monitoring of mechanical seals in high-end equipment. However, the limited reliability of indirect measurements and the compromises in the structural integrity of the original seal caused by implantable measurements pose constraints on the efficacy of monitoring wear in seals. Here, this study proposes a smart ultra-compact triboelectric reciprocating sealing system (UCTERS) capable of monitoring motion states and wear conditions. By utilizing the existing structure of commercial seals and applying abrasion-resistant coatings to the moving parts, the UC-TERS enables an ultra-compact design. The electrical output performances of various materials were investigated, and diamond-like carbon (DLC) coating and sealing made of polytetrafluoroethylene (PTFE) mixed with carbon fiber were selected to improve the self-powering and self-sensing capabilities. Variations in the output voltage and current caused by the load resistance were measured. Experiments involving various speeds and a constant speed were conducted to verify the self-sensing ability of the UC-TERS in detecting the motion state. In addition, a sealing wear test was performed to diagnose the wear conditions in the reciprocating mechanism based on the UC-TERS output. By combining the UC-TERS with deep learning algorithms, different wear conditions were accurately classified. Subsequently, the UC-TERS was applied to industrial servo actuators, and it demonstrated that it could achieve self-powering and self-sensing capabilities with a high reliability. The results of this study showcase the broad application potential of UC-TERS in the development of IoT.

Metal oxides have been extensively investigated in non-enzymatic biosensors for detecting diabetes owing to their electrochemical catalytic properties and excellent stability. However, lower conductivity and catalytic activity are major obstacles to the commercialization of metal oxide-based non-enzymatic glucose sensors. Herein, we present a novel flexible nonenzymatic glucose sensor utilizing graphene fiber (GF)/Au/Ni(OH)2 composite fiber. The integration of GFs enables a significant uptake of sensing molecules due to its expansive surface area and high electron mobility, ultimately resulting in a decrease in the detection limit. Consequently, the incorporation of Ni(OH)2 provides abundant attachment sites by introducing Au atoms, thereby promoting electron migration and enhancing sensitivity and detection limits. An impressive sensitivity (1095.63 µA mM−1 cm−2) within the detection range (5 µM–2.2 mM) of the integrated GF/Au/Ni(OH)2 fiber is achieved, leading to an incredibly low detection limit (0.294 µM). Additionally, the outstanding repeatability, anti-interference properties, and flexibility of the GF/Au/Ni(OH)2 sensors are obtained as well. Our findings offer a novel method for constructing nano embossments on GFs to achieve superior glucose detection capabilities in the field of wearable electronics in the future.

Stress tolerance plays a vital role in ensuring the effectiveness of piezoresistive sensing films used in flexible pressure sensors. However, existing methods for enhancing stress tolerance employ dome-shaped, wrinkle-shaped, and pyramidal-shaped microstructures in intricate molding and demolding processes, which introduce significant fabrication challenges and limit the sensing performance. To address these shortcomings, this paper presents periodic microslits in a sensing film made of multiwalled carbon nanotubes and polydimethylsiloxane to realize ultrahigh stress tolerance with a theoretical maximum of 2.477 MPa and a sensitivity of 18.092 kPa −1 . The periodic microslits permit extensive deformation under high pressure ( e.g ., 400 kPa) to widen the detection range. Moreover, the periodic microslits also enhance the sensitivity based on simultaneously exhibiting multiple synapses within the sensing interface and between the periodic sensing cells. The proposed solution is verified by experiments using sensors based on the microslit strategy for wind direction detection, robot movement sensing, and human health monitoring. In these experiments, vehicle load detection is achieved for ultrahigh pressure sensing under an ultrahigh pressure of over 400 kPa and a ratio of the contact area to the total area of 32.74%. The results indicate that the proposed microslit strategy can achieve ultrahigh stress tolerance while simplifying the fabrication complexity of preparing microstructure sensing films.

Integrated periodic structure reference materials are crucial for calibration in optical instruments and micro-computed tomography (micro-CT), yet they face limitations concerning a restricted measurement range, a single pattern type, and a single calibration parameter. In this study, we address these challenges by developing integrated periodic structure reference materials with an expanded measurement range, diverse pattern types, and multiple calibration parameters through a combination of photolithography and inductively coupled plasma (ICP) etching process. These reference materials facilitate high-efficiency and multi-value calibration, finding applications in the calibration of optical instruments and micro-CT systems. The simulations were conducted using MATLAB (R2022b) to examine the structure-morphology changes during the single-step ICP etching process. The variation rules governing line widths, periods, etching depths, and side wall verticality in integrated periodic structure reference materials were thoroughly evaluated. Linewidths were accurately extracted utilizing an advanced image processing algorithm, while average period values were determined through the precise Fast Fourier Transform method. The experimental results demonstrate that the relative errors of line widths do not exceed 17.5%, and the relative errors of periods do not exceed 1.5%. Furthermore, precise control of the etching depth was achieved, ranging from 30 to 60 μm for grids with line widths 2–20 μm. The side wall verticality exhibited remarkable consistency with an angle of 90° ± 0.8°, and its relative error was found to be less than 0.9%.

The flexible electronics have application prospects in many fields, including as wearable devices and in structural detection. Spintronics possess the merits of a fast response and high integration density, opening up possibilities for various applications. However, the integration of miniaturization on flexible substrates is impeded inevitably due to the high Joule heat from high current density (1012 A/m2). In this study, a prototype flexible spintronic with device antiferromagnetic/ferromagnetic heterojunctions is proposed. The interlayer coupling strength can be obviously altered by sunlight soaking via direct photo-induced electron doping. With the assistance of a small magnetic field (±125 Oe), the almost 180° flip of magnetization is realized. Furthermore, the magnetoresistance changes (15~29%) of flexible spintronics on fingers receiving light illumination are achieved successfully, exhibiting the wearable application potential. Our findings develop flexible spintronic sensors, expanding the vision for the novel generation of photovoltaic/spintronic devices.

Ultrahigh sensitivity and wide detection range are critical for flexible pressure sensors in the further application of electronic skin and wearable electronics. Here, a flexible pressure sensor with rGO coated on a micro cone array was fabricated. By using the molecular dynamics simulation to investigating the formation mechanism of rGO, its optimized micro-morphology can be obtained and understood for improving the performances of sen-sors. Both an ultrahigh sensitivity (133.003 kPa-1, < 40 kPa) and a wide detection range (0-300 kPa, >10 kPa-1) were remarkably achieved due to the multiple embossments within interfaces of rGO. Furthermore, the designed sensor using rGO with embossments enables several practical applications, showing a fast response time (27 ms) in child door lock monitoring and a distinct step-shape response in robotic arm load monitoring, respectively. And no frequency dependence under loading is also observed obviously. In addition, micro-pressure monitoring, including heart beat (excellent robustness over 10,000 cycles) and vocal cord vibration (sound track), can be monitored clearly owing to embossments morphology of rGO as well. The simulation model of sub -microstructures on rGO shows that the embossments can build the multiple contacts within the interfaces for higher signals output. The designed sub-microstructures of rGO can be an effective strategy to afford superior performances of pressure sensors for universal applications in physiological signal monitoring and physical motion analysis.

A nano-grating standard with accurate linewidth can not only calibrate the magnification of nano-measurement instruments, but can also enable comparison of linewidths. Unfortunately, it is still a challenging task to control the linewidth of nano-grating standards. Accordingly, in this paper, atomic layer deposition (ALD) was used to regulate the linewidth of the one-dimensional grating standards with a pitch of 1000 nm, fabricated by electron beam lithography (EBL). The standards were measured using an atomic force microscope (AFM) before and after ALD, and the linewidth and pitch of the grating were calculated through the gravity center method. The obtained results prove that the width of a single grating line in the standard can be regulated with great uniformity by precisely utilizing ALD. Meanwhile, the proposed method does not affect the pitch of grating, and the measurement uncertainty of standards is less than 0.16% of the pitch, thereby demonstrating a high surface quality and calibration reliability of the standards, and realizing the integration of linewidth and pitch calibration functions. Moreover, the precise and controllable fabrication method of the micro-nano periodic structure based on ALD technology has many potential applications in the fields of optoelectronic devices and biosensors.

Nano-steps, as classical nano-geometric reference materials, are very important for calibrating measurements in the semiconductor industry; therefore, controlling the height of nano-steps is critical for ensuring accurate measurements. Accordingly, in this study nano-steps with heights of 1, 2, 3 and 4 nm were fabricated with good morphology using atomic layer deposition (ALD) combined with wet etching. The roughness of the fabricated nano-steps was effectively controlled by utilizing the three-dimensional conformal ALD process. Moreover, the relationship between the surface roughness and the height was studied using a simulation-based analysis. Essentially, roughness control is crucial in fabricating nano-steps with a critical dimension of less than 5 nm. In this study, the minimum height of a nano-step that was successfully achieved by combining ALD and wet etching was 1 nm. Furthermore, the preconditions for quality assurance for a reference material and the influencing factors of the fabrication method were analyzed based on the 1 nm nano-step sample. Finally, the fabricated samples were used in time-dependent experiments to verify the optimal stability of the nano-steps as reference materials. This research is instructive to fabricate nano-geometric reference materials to within 5 nm in height, and the proposed method can be easily employed to manufacture wafer-sized step height reference materials, thus enabling its large-scale industrial application for in-line calibration in integrated circuit production lines.

Accurate temperature measurements can efficiently solve numerous critical problems and provide key information. Herein, a flexible micro-three-dimensional sensor, with a combination of platinum and indium oxide to form thermocouples, is designed and fabricated by a microfabrication process to achieve in situ real-time temperature measurements. The stability and reliability of the sensor are greatly improved by optimizing the process parameters, structural design, and preparation methods. A novel micro-three-dimensional structure with better malleability is designed, which also takes advantage of the fast response of a two-dimensional thin film. The as-obtained flexible temperature sensor with excellent stability and reliability is expected to greatly contribute to the development of essential components in various emerging research fields, including bio-robot and healthcare systems. The model of the application sensor in a mask is further proposed and designed to realize the collection of health information, reducing the number of deaths caused by the lack of timely detection and treatment of patients.

Smart gloves have played an increasingly important role in health monitoring, human-computer interaction and other fields. In order to make smart glove comfortable to wear, a flexible smart glove was fabricated in this paper. This kind of glove can obtain the magnitude and distribution of the pressure of palm and the bending degree of five fingers by using the corresponding signal acquisition system. According to the results displayed by the system, the pressure of various parts of the palm and the gestures can be judged. These conclusions can provide references for subsequent analysis.

Characteristics, such as large measurement range, good repeatability and stability, are the guarantee for a wide application of flexible three-dimensional force sensors in robots and other smart devices. In this research, a flexible three-dimensional force sensor is presented, whose structure includes force-sensitive cells, fixed under the bump and a support layer, filled around the force-sensitive cells. This setup allows the sensor to quickly recover, after the force is released, to ensure its excellent performance. The production method is very simple and has the advantage of large-scale and low-cost manufacturing. The sensor exhibited good repeatability and stability, after 25 000 cycles of loading and releasing, under 8 N force. Meanwhile, it has a large measuring range, which is 0–15 N in the direction of normal force and 0–5.5 N in the direction of shear force. The sensitivity of the sensor in the x, y, and z directions is 1.5321 V−1 N−1, 1.501 29 V−1 N−1, and 0.936 87 V−1 N−1, respectively. The load response time of the sensor is 33 ms and the unload recovery time of 18 ms. Regarding practical applications, the sensor shows good prospects. For example, the sensor and its array can be installed on the manipulator to sense the magnitude and location of the three-dimensional force; in the case of the flexible smart keyboard, the presented sensor array can save space significantly and recognize multiple specific input features, in order to enhance information security; while as a car controller, it is multi-functional integrated and portable, thus showing great potential as replacement to the traditional operating methods.

The crosstalk and flexibility are two problems in three-dimensional force sensor with sandwich structure. In this paper, a piezoresistive flexible three-dimensional force sensor is presented. It consists of three parts: the bump layer, the pressure sensitive layer and the flexible electrode layer. The threedimensional force sensor has several independent pressure units isolated by PDMS and single-layer electrode structure. This kind of structure not only can suppress the crosstalk, but also has better flexibility. The three-dimensional force is measured by each layer cooperated. The measuring principle and preparation method of the three-dimensional force are studied here. It shows that the anti-crosstalk piezoresistive three-dimensional force sensor is realizable in the field of intelligent perception such as dexterous robot hand.