High-temperature sensors are irreplaceable for extreme-environment monitoring in aerospace, automotive, marine, and industry applications. This review synthesizes critical advances in materials, sensing principles, drift compensation, signal transmission, and encapsulation reliability. We analyze high-temperature-resistant ceramics, metals, crystalline materials, wide-band gap semiconductors, and high-entropy alloys, highlighting their operational mechanisms under high-temperature conditions. Subsequently, seven typical high-temperature sensing principles including fiber Bragg grating, LC resonance, Hall effect, magnetostriction, piezoelectric effect, Seebeck effect, and thermoelectric effect are expounded. Furthermore, the roles of software compensation strategies (curve fitting and neural networks) and hardware compensation approaches (material optimization and circuit design) in suppressing temperature drift are discussed. In addition, the thermomechanical reliability design of packaging technologies such as high-temperature tubular encapsulation, solid-state isolation encapsulation, substrate encapsulation, and leadless encapsulation is comprehensively reviewed. Finally, the operational performance of high-temperature sensors in high-temperature scenarios, such as automotive powertrains, aircraft engines, and marine turbines, is detailed. This review provides theoretical guidance and technical references for material selection, sensing principle innovation, and engineering implementation of high-temperature sensors.

Simultaneously achieving high sensitivity and a broad sensing range remains a fundamental challenge for flexible capacitive pressure sensors. Herein, we report a synergistic multiscale architecture featuring a polydimethylsiloxane/multi-walled carbon nanotube nanocomposite dielectric, asymmetrically patterned with nanogratings and irregular micro-protrusions, paired with an electrospun thermoplastic polyurethane nanofibrous network acting as an elastic buffer. By decoupling stress distribution mechanisms, this hierarchical design optimizes performance across all pressure regimes. At low pressures, the nanogratings induce severe localized stress to rapidly activate the percolation effect, maximizing initial sensitivity. Conversely, at high pressures, the micro-protrusions and TPU layer progressively redistribute stress, effectively delaying mechanical saturation. Consequently, the sensor delivers an ultrahigh initial sensitivity of 12.34 kPa-1 across a broad 200 kPa working range, alongside rapid response (<30 ms) and robust durability (>5000 cycles). Demonstrating exceptional versatility in precise joint kinematic tracking, robotic grasping, and spatial pressure mapping, this structural engineering strategy establishes a compelling paradigm for next-generation flexible sensors in smart healthcare and human-machine interfaces.

Flexible capacitive pressure sensors hold tremendous promise for human health monitoring, human-machine interfaces, and wearable electronics due to their excellent conformability and high sensitivity. Nevertheless, breaking the inherent trade-off between high sensitivity and a broad detection range remains a challenge. Herein, we rationally design a hierarchical micro/nanostructured capacitive pressure sensor. This architecture strategically integrates a conical microcavity layer to optimize mechanical compressibility, a SiO2 micro/nanosphere layer to regulate interfacial contact behavior, and an electrospun nanofiber network to reinforce structural robustness, working synergistically to achieve superior sensing performance. Empowered by these synergistic components, the sensor exhibits an outstanding comprehensive performance, achieving a high sensitivity of 3.779 kPa-1, a broad sensing range of up to 255 kPa, a rapid response time (48 ms), and remarkable mechanical durability (over 6000 cycles under a high pressure of 150 kPa). Consequently, the sensor demonstrates versatile capabilities across diverse scenarios, including continuous human physiological and kinematic monitoring, non-destructive fruit and vegetable sorting, high-resolution pressure array sensing, and a backpack-integrated posture assessment system. This work establishes a versatile hierarchical design paradigm for next-generation flexible capacitive sensors, paving the way for superior performance and real-world applications in intelligent perception systems.

Integrating multimodal sensing within a single, compact footprint is pivotal for next-generation intelligent systems, particularly embodied intelligent robots, precision medicine, and smart manufacturing, where spatially co-located perception of multiple physical cues is essential. Conventional flexible sensors, however, suffer from severe cross-talk when simultaneously detecting distinct stimuli at the same location, leading to signal ambiguity and degraded fidelity. Herein, we report a flexible pressure-humidity bimodal sensor achieved through a synergistic structure-material co-design strategy that couples a micro-nano hierarchical structure with multifunctional electrospun nanofibrous layers. The device delivers high-fidelity, real-time responses to pressure (sensitivity: 0.0955 kPa(-1) over 0-10 kPa) and humidity (0.1245 k Omega/%RH), exhibits robust cycling stability (>3000 cycles), and achieves small crosstalk (<4.27%). Preliminary experimental and simulation results demonstrate the sensor's future potential in two proof-of-concept demonstrations: non-destructive assessment of blueberry maturity based on flesh firmness and skin moisture, and co-located monitoring of interface pressure and skin wetness for proactive assessment of pressure ulcer risk in bedridden patients. This work establishes a "micro-nano architecture/multifunctional material" co-design paradigm, providing a scalable pathway enabling electronic skin to perceive diverse and complex environments with high integration and low interference.

Inorganic nanoyarns with high electrical conductivity, tunable redox activity, and outstanding chemical/thermal stability are promising components for high-performance multifunctional fibers. However, integrating inorganic functionality with the softness, durability, and processability required for wearable fiber systems remains a major challenge. Here we present ultrasoft core–shell nanoyarns composed of inorganic nanoribbon cores and polymer shells with exceptional mechanical compliance while maintaining high electrical and chemical performance. The inorganic core provides multifunctionality and structural diversity with single-layer, particle-decorated, and multilayer sandwich architectures. A grounded-core electrospinning strategy is introduced to form porous polymer shells around the inorganic cores, providing mechanical reinforcement, electrical insulation, and diffusion pathways for reactive species within a resilient, flexible framework. The proposed core–shell nanoyarns function as efficient water-splitting electrodes, deliver a high volumetric energy density in fiber-type supercapacitors, and operate as force sensors capable of detecting forces at the tens-of-micronewton level. These results establish the core–shell nanoyarn as a universal and scalable platform for wearable energy and sensing systems.

Developing hydrogen (H2) sensors with ultralow detection limits, high response, and room-temperature operation is critical for the safe utilization of H2 energy. Herein, we report a highly sensitive H2 sensor based on palladium nanoparticle (Pd NP)-decorated silicon microcone (Si MC) arrays, with a systematic investigation of metal deposition conditions. Large-area, uniform, and smooth Si MC arrays were fabricated via metal-assisted chemical etching (MACE). The Pd deposition angle (0-90°) plays a vital role in sensing performance. The optimized 3 Pd-75° sensor (3 nm Pd, 75° deposition) exhibits an exceptional response of 2148.9% toward 10,000 ppm H2 at room temperature, along with fast recovery (∼4 s), good humidity tolerance, long-term stability, and excellent selectivity. Notably, it achieves an ultrawide quantitative detection range from 10 ppb to 2000 ppm. Furthermore, Pt modification reveals a trade-off between catalytic activity and electrical response: while Pt accelerates H2 dissociation and diffusion, it reduces response magnitude due to active site blocking and enhanced conduction pathways. The superior sensing performance arises from the synergistic effects of Pd catalysis, Pd/Si interfacial charge modulation, and the high surface area of the Si MC architecture. This work provides a promising strategy for low-power, high-performance room-temperature H2 sensing.

The flexible plasmonic sensor has triggered tremendous efforts for on-demand, on-site, in-situ, and real-time monitoring applications due to its ideal conformal contact, excellent optical tunability, high mechanical stability, and sensing repeatability. However, the corrosion resistance of flexible plasmonic sensors is often overlooked and remains an intractable obstruction. Herein, flexible fabric-like plasmonic nanostructures were developed and investigated in detail as a promising platform to resist chemical corrosion. The underlying mechanism for the chemical corrosion resistance of this fabric-like plasma nanostructure stems from two aspects: firstly, X-ray photoelectron spectroscopy (XPS) results demonstrate that oxygen plasma etching fractures the Si- O-Si and Si-C bonds, generating abundant Si-OH and C-OH bonds on the surface of the flexible substrate, thereby promoting condensation reactions between the flexible substrate material and Au, resulting in stable Si-O-Cr and C-O-Cr bonds; secondly, comparative experimental results indicate that the anchoring effect of the nanostructure with noble metals hinders the penetration and corrosion of liquid molecules at the interface. As a result, this plasmonic sensor with a fabric-like nanostructure can remain stable for more than 36 h in acidic, alkaline, and neutral solutions, and accurately identify target molecules at ultra-low concentrations. This work highlights the importance of surface nanostructures in enhancing acid and alkali resistance of flexible substrates, providing a reference strategy for the design and fabrication of other corrosion-resistant flexible sensors.

Suspended nanostructures have found widespread applications (e.g., photodetectors, displays, and sensors) due to their unique properties, such as high surface‐to‐volume ratio (H‐SVR), high mass transport, and low‐power etc. Various suspended nanostructures have been fabricated using existing nanofabrication techniques (e.g., electron beam, optical lithography, and layer‐by‐layer assembly). However, realizing the fabrication of double‐layer suspended nanostructures remains a significant challenge. Herein, a method for fabricating large‐area, uniform, and well‐arrayed double‐layer suspended nanostructures is presented using plasma‐assisted nanotransfer printing (PA‐nTP). Double‐layer nanostructures are prepared via nanoimprint lithography and e‐beam evaporation. Oxygen plasma treatment reduces the bonding force between the nanoimprinted resin, allowing gold nanodots suspended atop nanohole structures to be transferred onto the silicon (Si) substrate. The developed structures serve as substrates for surface‐enhanced Raman scattering (SERS) and templates for hollow Si nanostructures. The Au‐coated 3D double‐layer suspended nanostructures enhance SERS performance by a factor of 1.5 × 10 6 compared to flat substrates. Additionally, hollow Si nanostructures fabricated through metal‐assisted chemical etching (MACE) improve the hydrogen (H 2 ) sensor response from 2.54% to 165% under 1% H 2 , compared to solid Si nanostructures. Therefore, this method provides a feasible pathway for advancing nanofabrication in applications such as biological/chemical sensors and optoelectronics.

Flexible capacitive pressure sensors hold great promise for next-generation intelligent systems, including secure human-machine interfaces, industrial IoT, and wearable healthcare. However, their performance is fundamentally constrained by the trade-off between sensitivity and sensing range in complex, multidimensional environments. Here, inspired by the natural architecture of Eragrostis ferruginea, this work presents a bioinspired pressure sensor featuring a double-layer V-shaped architecture using carbon nanotubes/polydimethylsiloxane (CNTs/PDMS) composites. A dual-level cascaded stress modulation strategy is induced within the dielectric layer to simultaneously enhance sensitivity and broaden the sensing range. Finite element analysis simulation reveals that the hierarchical design effectively redistributes mechanical stress, optimizing the capacitive response under varied pressures. The fabricated sensor exhibits a high sensitivity of 2.889 kPa-1, a broad detection range up to 210 kPa, a fast response time of 30 ms, and excellent durability over 10 000 cycles at 80 kPa. Application scenarios, including dual-layer data encryption, non-destructive fruit ripeness classification, and plantar pressure mapping, demonstrate the sensor's versatility and multifunctional integration capabilities. This work provides a scalable material and structural design strategy for advanced flexible electronics with enhanced sensing performance across diverse interactive platforms.

The development of reliable, highly sensitive hydrogen sensors is crucial for the safe implementation of hydrogen-based energy systems. This paper proposes a novel way to enhance the performance of hydrogen sensors through integrating Pd-SnO2 nanofilms on the substrate with silicon nanowires (SiNWs). The samples were fabricated via a simple and cost-effective process, mainly consisting of metal-assisted chemical etching (MaCE) and electron beam evaporation. Structural and morphological characterizations were conducted using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The experimental results showed that, compared to those without SiNW structure or decorative Pd nanoparticles, the Pd-decorated SnO2 nanofilm integrated on the SiNW substrates exhibited significantly improved hydrogen sensing performance, achieving a response time of 9 s at 300 °C to 1.5% H2 and a detection limit of 1 ppm. The enhanced performance can be primarily attributed to the large surface area provided by SiNWs, the efficient hydrogen spillover effect facilitated by Pd nanoparticles, and the abundant oxygen vacancies present on the surface of the SnO2 nanofilm, as well as the Schottky barrier formed at the heterojunction interface between Pd and SnO2. This study demonstrates a promising approach for developing high-performance H2 sensors characterized by ultrafast response times and ultralow detection limits.

Flexible printed electronics represent a cutting‐edge technology leveraging functional inks to fabricate electronic circuits and components on diverse flexible substrates. Various advanced printing processes enable the production of computer‐controlled patterns with superior resolution and flexibility. Advances in low‐temperature sintering techniques have significantly propelled the evolution of flexible printed electronics by reducing thermal impact on substrates, ensuring high‐quality device fabrication. Functional nanomaterial inks serve as the cornerstone of this technology, with metallic nanoparticle inks being widely utilized for their superior electrical conductivity, facile synthesis, and commendable biocompatibility. Here, we comprehensively review the synthesis and processing of metallic nanoparticle inks and critically comment on different types of metallic nanoparticle inks, and believe that composite metallic nanoparticle inks have more advantages in reducing cost and improving comprehensive performance. In addition, this paper summarizes the various printing processes and sintering techniques, emphasizing the printing mechanisms and the recent advances in low‐temperature sintering technology. The applications of metallic nanoparticle inks in various scenarios, such as sensors, wireless technologies, energy storage and electroluminescent devices, are summarized. Lastly, the current challenges facing metallic nanoparticle inks are critically analyzed, and forward‐looking strategies and advances aimed at addressing these obstacles are proposed.

Although porous metal nanostructures with densely distributed nanogaps offer exceptional potential to significantly enhance surface-enhanced Raman scattering (SERS) signals, fabrication of ultrahigh-density nanogaps that increase the density and intensity of hotspots remains a critical challenge. In this study, we fabricate hierarchically engineered porous Au nanostructures (P-Au NSs) with ultradense hotspots on various substrates using a nanotransfer printing (nTP) system. Ultradense P-Au nanowires exhibit superior plasmonic coupling at stacked cross-points, which can be attributed to their increased contact areas arising from porous architecture. In addition, experimental results and numerical simulations confirm the plasma-treated P-Au nanowire on a mirror (pPAN on M) structure produced via an advanced nTP process further enhancing hotspot formation. The SERS performance was evaluated using 4-mercaptobenzoic acid (4-MBA) and thiram with an optimized substrate achieving a Raman enhancement factor of 1.21 × 1012 and limit of detection for 4-MBA of ∼6.46 × 10−13 M. These findings underscore the significant potential of the developed P-Au NSs not only for ultrasensitive SERS detection but also for diverse applications in energy storage, catalysis, and optoelectronics.

The rational design of sensing materials is pivotal for enhancing gas detection capabilities, especially for hydrogen (H2), a clean yet highly flammable energy carrier. Despite extensive efforts, achieving reliable and sensitive H2 detection under ambient conditions remains a significant challenge. Here, we present a highly sensitive room-temperature H2 sensor based on palladium (Pd)-decorated porous silicon (Si) microcone arrays. The porous microcones were fabricated via photolithography and metal-assisted chemical etching, followed by Pd deposition using angle-controlled electron beam evaporation. By systematically tuning the Pd thickness and deposition angle, the sensor achieved an optimal response of 347% to 10,000 ppm of H2 and a detection limit of 1 ppm at room temperature. The porous Si microcone structure offers a large surface area and efficient gas diffusion pathways, while oblique-angle Pd deposition enhances catalytic activity and facilitates interfacial modulation. The sensor also exhibits a broad dynamic detection range (0.0001-2%), excellent selectivity, and long-term stability. Furthermore, codecoration with Ag, Au, or Pt enables further tuning of response and recovery times. The demonstrated compatibility with Si-based processes underscores its potential for integration into next-generation low-power H2 monitoring systems.

Accurate detection and identification of hazardous gases in complex environments are essential for ensuring human health and safety in modern industrial systems. Although sensing technologies are rapidly advancing toward miniaturization, low power consumption, and multifunctionality, the scalable and reliable integration of complex nanostructures with functional materials remains a significant challenge. Here, we present a scalable and material-compatible strategy for fabricating suspended half-pipe nanostructures on the nanoimprinted substrates via integrating vapor-phase solvent-assisted nanotransfer printing with nanoimprint lithography. The resulting hierarchical architecture facilitates efficient gas-surface interactions and improves sensing performance under variable environmental conditions. We further demonstrate a self-heating gas sensing platform based on half-pipe nanostructures functionalized with SnO2 and noble metals (Au, Pd, Pt), enabling accurate classification of H2, CH4, H2S, and NH3. With the assistance of machine learning algorithms, the platform achieves a recognition accuracy approaching 100 %. Furthermore, an integrated Pt nano heater delivers efficient thermal regulation within the range of 100-500 degrees C, establishing optimal operating conditions for gas-sensitive materials while significantly reducing overall power consumption. This work offers a universal and scalable fabrication approach for advanced gas sensors, paving the way for intelligent, energy-efficient, and high-selectivity sensing platforms suitable for next-generation industrial and environmental monitoring.

Hydrogen's flammability and 4% explosion limit make its parts per billion-level detection essential for safety monitoring. However, conventional metal oxide semiconductor (MOS) sensors show low sensitivity and selectivity due to limited active sites. Here, Pd-loaded ZnTiO3/ZnO heterojunction nanotubes were fabricated by coaxial electrospinning, using a Zn(Ac)2-PdCl2-PVP/DMF outer solution and a Ti(OC4H9)4-PAN/DMF inner solution, followed by staged pyrolysis to generate hollow structures. The differential decomposition of polymers produced a hollow nanotube architecture that increases the surface area, provides abundant active sites, and facilitates gas diffusion. Meanwhile, the coupling of oxygen-vacancy-rich ZnTiO3, direct-bandgap ZnO, and PdO formed efficient p-n heterojunctions, promoting charge separation and surface reactivity. The optimized sensor (ZnTiO3/ZnO = 0.65:1, Pd = 3 wt %) exhibited an ultrahigh response (Ra/Rg = 43,680) to 1000 ppm of H2 at 260 °C, a 50 ppb detection limit, and 20/162 s response/recovery times. Excellent selectivity is achieved, with hydrogen signals orders of magnitude higher than those for NH3, C3H6O, CH4, and C2H6O. Mechanistic analysis indicates that PdO lowers the activation energy for H2 dissociation, while heterojunction band bending enhances oxygen adsorption and charge transport. This work provides a scalable strategy for high-performance hydrogen sensors with ultralow detection limits and strong anti-interference capability.

The development of hydrogen (H2) sensors with parts-per-billion (ppb)-level detection limits, high sensitivity, and room-temperature operation is of paramount importance for ensuring industrial safety and advancing H2-based energy technologies. While numerous studies have reported ppb-level detection, challenges such as room-temperature operation, selectivity, and integration remain significant obstacles. Here, we report a high-performance H2 sensor capable of detecting ppb-level H2 at room temperature with exceptional sensitivity and reliability. The sensor is based on palladium nanoparticles (Pd NPs)-functionalized silicon (Si) nanoforest structures, which offer a high surface-to-volume ratio (H-SVR), facilitating enhanced gas adsorption and interaction. The optimized sensor exhibits a remarkable response of 1685% to 1% H2 at room temperature, along with an ultralow detection limit of 50 ppb. In addition, it demonstrates excellent batch-to-batch reproducibility, strong selectivity, and adaptability to high-humidity environments, highlighting its outstanding H2 sensing performance. The superior H2 sensing performance is attributed to the synergistic effects of Pd-catalyzed H2 dissociation, enhanced adsorption due to the high surface area of the Si nanoforest, and charge modulation at the Pd/Si Schottky junction. The developed sensor holds significant potential for advancing next-generation H2 sensing platforms, which are critical for industrial safety, environmental monitoring, and H2 economy applications.

Flexible piezoresistive sensors are crucial for wearable electronics and intelligent robotics due to their high sensitivity and wide linear range. However, achieving both wide linear range and high sensitivity remains challenging. A high-performance MXene-based flexible piezoresistive pressure sensor featuring hierarchical structural engineering is reported. The sensor integrates a microsphere-regulated barrier layer to modulate contact behavior, a MXene/MWCNTs-PDMS composite for stable conductivity, and an outer PDMS membrane with inverted conical microstructures to enhance sensitivity. This design achieves an ultra-wide detection range with a three-stage linear response (0-1228.75 kPa) and an excellent sensitivity (up to 9041.8 kPa-1), maintaining stability over 5000 cycles at 625 kPa. The device demonstrates reliable detection of physiological signals and material recognition, offering a scalable solution for wearable electronics and intelligent robotics. This work is expected to provide new insights into the design of next-generation high-performance flexible sensing systems.

Silicon nanowires (Si NWs) have attracted considerable interest owing to their distinctive properties, which render them promising candidates for a wide range of advanced applications in electronics, photonics, energy storage, and sensing. However, challenges in achieving large-scale production, high uniformity, and shape control limit their practical use. This study presents a novel fabrication approach combining nanoimprint lithography, nanotransfer printing, and metal-assisted chemical etching to produce highly uniform and shape-controlled Si NW arrays. By optimizing the process parameters, Si NWs with various diameters (100, 200, and 400 nm) are successfully fabricated on 6-inch wafers, achieving high uniformity confirmed through statistical and surface reflection analyses. Furthermore, a conformal coating of titanium nitride on the uniform Si NWs enables broadband absorption with average absorption of 75% in the wavelength range from 250 to 2500 nm, demonstrating their potential for next-generation optoelectronic devices. These findings provide valuable insights for the scalable production of Si NWs and their integration into high-performance electronic systems.

The flexible capacitive pressure sensors exhibit significant potential for applications in wearable health monitoring, soft robotics, and human-computer interaction. However, achieving both high sensitivity and a wide response range simultaneously remains challenging. To address this, we designed a sensor incorporating a conical-protrusion porous microstructure inspired by the porous architecture of sponges. This structure enables a piecewise linear response across three distinct deformation stages: compression of the conical protrusions at low pressures, deformation of the porous framework at intermediate pressures, and bulk material densification at high pressures. This multistage mechanism effectively reconciles the sensitivity-range tradeoff, yielding a sensor with high sensitivity (2.996 kPa-1), a broad operational range (0-500 kPa), fast response time (98 ms), and durability exceeding 8000 cycles under 300-kPa loading. Through demonstrations in human health monitoring and human-machine interaction, we highlight the sensor's applicability to next-generation intelligent sensing systems. This work introduces a novel structural strategy for high-performance flexible capacitive pressure sensors, offering a pathway to balance sensitivity and dynamic range in flexible capacitive pressure sensors