Sensors and Actuators A-physical最新文献_第6页

A novel miniaturized paraffin actuator with Peltier-controlled cooling and graphene thermal conductivity enhancers 一种新型小型化石蜡致动器，具有珀耳梯控制冷却和石墨烯导热增强剂

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-10 DOI: 10.1016/j.sna.2026.117482

Stefano Morese , Kiran Paul Nalli , Uwe Pelz , Swathi Krishna Subhash , Suman Kundu , Frank Goldschmidtböing , Peter Woias

Paraffin-based microactuators show great potential in the field of phase change materials actuators owing to their high mechanical work capacity and large thermal expansion. In recent years, researchers have directed efforts toward enhancing the response times of these systems, by mixing paraffin with thermal conductivity enhancers or by optimizing their designs. However, no previous research has focused on improving the cooling time of a paraffin actuator, which is essential for ensuring faster cyclic performance and adaptable thermal control in environments where temperature fluctuates. In this study, we present the first miniaturized thermoelectric cooler (µTEC)-paraffin-based actuator. This design utilizes the µTEC to control the phase change of paraffin, by heating or cooling it on demand. Furthermore, we investigated the use of graphene nano-platelets (GnPs) as a thermal conductivity enhancer and its effect on design performance. The system featured an aluminum cavity filled with a paraffin composite formulation, a µTEC device and a copper heat sink. The results showed that the presence of a µTEC could enable not only cyclic actuation, but also reduced the actuator reset time to approximately 20 % of the original duration. The device also demonstrated a peak work density and efficiency around 25.6 kJ/m³ and 17.8 × 10⁻⁶, respectively. These results place our actuator system among the highest-performing flexible membrane-based paraffin microactuators reported in the literature with the additional benefit of controlled and fast cooling.

石蜡基微致动器具有机械功容量大、热膨胀大等优点，在相变材料致动器领域具有很大的发展潜力。近年来，研究人员一直致力于通过将石蜡与导热增强剂混合或优化设计来提高这些系统的响应时间。然而，之前没有研究关注于提高石蜡致动器的冷却时间，这对于确保在温度波动的环境中更快的循环性能和适应性热控制至关重要。在这项研究中，我们提出了第一个小型化热电冷却器（µTEC）-石蜡基致动器。该设计利用µTEC控制石蜡的相变，根据需要加热或冷却石蜡。此外，我们还研究了石墨烯纳米片（GnPs）作为导热增强剂的使用及其对设计性能的影响。该系统的特点是一个铝腔填充石蜡复合配方，一个µTEC装置和一个铜散热器。结果表明，µTEC的存在不仅可以实现循环驱动，还可以将执行器复位时间减少到原始持续时间的约20% %。该器件的峰值工作密度和效率分别约为25.6 kJ/m3和17.8 × 10−6。这些结果使我们的致动器系统在文献中报道的性能最高的柔性膜基石蜡微致动器中具有控制和快速冷却的额外好处。

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引用次数: 0

Floating PBTTT-graphene quantum dots composite coated thin film transistor for ammonia sensing 用于氨传感的浮动pbttt -石墨烯量子点复合涂层薄膜晶体管

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-09 DOI: 10.1016/j.sna.2026.117477

Nikhil Nikhil , Chandan Kumar , Srinu Gangolu

Conventionally pristine conducting polymer-based thin film transistors (TFTs) are used for sensing applications, but sensitivity is limited. In this article, the composite of conductive polymer and quantum dots is exploited for the improvement in the sensitivity towards ammonia. Poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene] (PBTTT-C14) or a simple PBTTT solution is mixed with as-synthesized graphene quantum dots (GQDs) solution for the preparation of PBTTT-GQDs composite. Unidirectional floating-film transfer method (UFTM) deposited PBTTT- GQDs composite on a Si/SiO₂ substrate-based TFT is fabricated. The fabricated PBTTT-GQDs composite-based TFT provides performance enhancement due to the self-assembled and oriented film by the UFTM technique, as well as the incorporation of GQDs in the polymer framework. The PBTTT-GQDs composite-based TFT has achieved higher field effect mobility as well as gas response up to ∼84.2 % for 25 ppm of ammonia. The composite-based ammonia sensor also exhibits improvement in detection limit and response/recovery time.

传统上，原始导电聚合物薄膜晶体管（TFTs）用于传感应用，但灵敏度有限。本文利用导电聚合物和量子点的复合材料来提高对氨的灵敏度。将聚[2,5-二（3-十四烷基噻吩-2-基）噻吩]（PBTTT- c14）或简单的PBTTT溶液与合成的石墨烯量子点（GQDs）溶液混合，制备PBTTT-GQDs复合材料。采用单向浮膜转移法（UFTM）在Si/SiO2基TFT上沉积PBTTT- GQDs复合材料。制备的PBTTT-GQDs复合基TFT由于UFTM技术的自组装和定向膜以及GQDs在聚合物框架中的结合而提供了性能增强。PBTTT-GQDs复合基TFT在25 ppm的氨气条件下获得了更高的场效应迁移率和高达84.2 %的气体响应。基于复合材料的氨传感器在检测限和响应/恢复时间方面也有改善。

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引用次数: 0

Synergistic effect of silver nanoparticles and carbon nanotubes in flexible composite films for boosted photothermoelectric properties 纳米银和碳纳米管在柔性复合薄膜中对提高光热电性能的协同效应

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-09 DOI: 10.1016/j.sna.2026.117476

Yan Ma , Haigang Hou , Dongliang Zhang , Jian Yang , Yuanzhi Pan , Guiwu Liu , Junlin Liu , Guanjun Qiao

Against the backdrop of the global low-carbon energy transition, the Photothermoelectric Effect has garnered considerable attention as an efficient route for light-to-electricity conversion. Single-walled carbon nanotubes (CNTs) stand out as potential substrates for photothermoelectric thin films, owing to their broad-spectrum light absorption and exceptional electrical properties. Nevertheless, they are hindered by inherent bottlenecks: insufficient light absorption intensity and excessively high thermal conductivity, which impede the maintenance of temperature differences. In this study, a silver nanoparticles (Ag NPs)-decorated CNT composite thin film (CNT@Ag) was constructed. The photothermal properties of the CNT@Ag film were 57 % higher than those of the Raw CNT as the local irradiation was applied. Furthermore, the composite film achieved a photovoltage of 0.2 mV, 2.86 times that of the Raw CNT. Current-voltage profiles, position-sensitive photovoltage, and synchronized thermal-voltage data verify that the electrical signal originates from the PTE effect. This research deepens the understanding of the PTE effect mechanism dominated by metal/carbon nanotube heterojunctions and provides a basis for the design of high-performance light energy conversion materials and the material development of intelligent sensing devices.

在全球低碳能源转型的背景下，光热电效应作为光-电转换的有效途径受到了广泛关注。单壁碳纳米管（CNTs）由于其广谱光吸收和特殊的电学性能而成为光热电薄膜的潜在衬底。然而，它们受到固有瓶颈的阻碍：光吸收强度不足和过高的热导率，这阻碍了温差的维持。在本研究中，构建了银纳米粒子（Ag NPs）修饰的碳纳米管复合薄膜（CNT@Ag）。在局部辐照下，CNT@Ag薄膜的光热性能比原始碳纳米管高57 %。此外，复合薄膜的光电压达到0.2 mV，是原始碳纳米管的2.86倍。电流电压曲线、位置敏感光电压和同步热电压数据验证了电信号源于PTE效应。本研究加深了对以金属/碳纳米管异质结为主的PTE效应机理的认识，为高性能光能转换材料的设计和智能传感器件的材料开发提供了依据。

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引用次数: 0

Magnetic-driven micromixer induced by oscillatory ferrofluid droplets as on-demand soft microactuators 由振荡铁磁流体液滴诱导的磁驱动微混合器作为按需软微执行器

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-09 DOI: 10.1016/j.sna.2026.117475

Amir Mohammad Haghgoo , Tina Hajihadi Naghash , Majid Ghassemi , Mohamad Ali Bijarchi , Mohammad Behshad Shafii

Using ferrofluids as smart materials in micromixers for achieving homogeneous mixing can be taken into account as a promising tool for improving the total efficiency of microfluidic platforms. A wide range of scenarios for employing the ferrofluid, as a miscible stream with reactants, have been explored to enhance mixing. However, the function of the ferrofluid as an immiscible agent in mixing is overlooked. Therefore, in this study, for the first time, the effect of oscillating a train of ferrofluid droplets as a controllable and on-demand actuator for ameliorating mass transfer in a 3D-printed micromixer is experimentally investigated. Another motivation for conducting this study is to meet the request of mixing two miscible fluids with the help of ferrofluid droplets as immiscible actuators in less contact with the biological reactant along with less impact on the final properties of the product. The movement of these magnetized droplets across to the flow direction becomes possible by a linear-moving magnet. By adjusting the influencing parameters including miscible fluids and ferrofluid flow rates, magnet movement frequency, magnet diameter, displacement amplitude, and the number of magnets the harmonic oscillations of bio-compatible ferrofluid droplets are comprehensively surveyed. The results show that by switching the magnetic system from off to on, the mixing index in the best case increases from 0.21 to 0.89. Thanks to the controllability of ferrofluid droplets, this novel idea offers an effective solution to intensify microfluidic mixing efficiency and can pave the way for other biomedicine and engineering applications.

在微混合器中使用铁磁流体作为智能材料来实现均匀混合，是提高微流控平台总效率的一种有前途的工具。铁磁流体作为一种与反应物混相的流体，已经被广泛地应用于各种场景中，以加强混合。然而，铁磁流体作为一种非混相剂在混合中的作用却被忽视了。因此，在本研究中，首次实验研究了在3d打印微混合器中振荡铁磁流体液滴作为可控按需执行器改善传质的效果。进行这项研究的另一个动机是为了满足混合两种可混相流体的要求，借助铁磁流体液滴作为不混相执行器，在与生物反应物接触较少的情况下，对产品的最终性能影响较小。这些被磁化的液滴通过线性移动的磁铁向流动方向移动成为可能。通过调整混相流体和铁磁流体流速、磁体运动频率、磁体直径、位移幅值和磁体数量等影响参数，对生物相容性铁磁流体液滴的谐波振荡进行了全面研究。结果表明，通过将磁性系统由关转通，混合指数由0.21提高到0.89。由于铁磁流体液滴的可控性，这一新颖的想法为增强微流体混合效率提供了有效的解决方案，并为其他生物医学和工程应用铺平了道路。

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引用次数: 0

A flexible modular neural interface for investigating functional connectivity between deep brain structures and the cerebral cortex 一个灵活的模块化神经接口，用于研究脑深部结构和大脑皮层之间的功能连接

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-08 DOI: 10.1016/j.sna.2026.117470

Sehwan Park , Seungjun Lee , Haeyun Lee , Minseok Kim , Jimin Lee , Namsun Chou , Hyogeun Shin

Understanding the connectivity between deep brain structures and the cerebral cortex is crucial for unraveling complex brain functions. However, existing neural interfaces are mostly limited to studying connections within either deep brain regions or the cortex. Herein, we present a flexible modular neural interface in which multiple modules comprising a flexible neural probe, an optical fiber, and a micro-needle for drug delivery can be integrated. This enables precise stimulation of various deep brain regions and simultaneous cortical signal measurements in response to various stimuli. The system enables the flexible positioning of modules at different depths, thereby supporting EEG signal recording and providing versatile targeting and modulation of neural circuits. The interface facilitates detailed investigations into functional connectivity by enabling localized stimulation while capturing neural activity from both deep brain structures and cortical areas. The results of validation experiments indicate that the system effectively induced epileptic-like signals in the cortex of anesthetized mice through deep brain stimulation and enabled measurement thereof. In addition, localized intracerebral drug delivery produces clear modulation of cortical EEG signals, demonstrating effective multimodal integration under physiological conditions. This adaptable modular design offers significant potential for expanding research into neural mechanisms and probing interactions between deep brain structures and the cortex with high precision.

了解大脑深层结构和大脑皮层之间的联系对于揭示复杂的大脑功能至关重要。然而，现有的神经接口大多局限于研究大脑深层区域或皮层内的连接。在此，我们提出了一种灵活的模块化神经接口，其中包含柔性神经探针，光纤和用于药物递送的微针的多个模块可以集成。这使得精确刺激不同的大脑深部区域和同时皮层信号测量响应于各种刺激。该系统能够在不同深度灵活定位模块，从而支持脑电图信号记录，并提供神经回路的多功能定位和调制。该接口通过实现局部刺激，同时捕获来自大脑深部结构和皮层区域的神经活动，从而促进了对功能连接的详细研究。验证实验结果表明，该系统通过深部脑刺激在麻醉小鼠皮层有效诱导癫痫样信号并使其能够测量。此外，局部脑内给药对皮层脑电图信号产生明显的调节，表明生理条件下有效的多模态整合。这种适应性强的模块化设计为扩展神经机制的研究以及高精度地探测脑深部结构和皮层之间的相互作用提供了巨大的潜力。

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引用次数: 0

Low-noise AC current measurement with a single-element magnetoresistive sensor and lock-in amplification 用单元件磁阻传感器和锁相放大进行低噪声交流电流测量

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-08 DOI: 10.1016/j.sna.2026.117469

Diego Ramírez Muñoz , Rafael García-Gil , Sandra Soriano Díaz , Carlo Alfisi , Susana Cardoso , Paulo P. Freitas

In this paper, a magnetoresistive (MR) sensor implemented with a single MR element, instead of the usual bridge configuration, has been developed for alternating (AC) current measurement, including the design of its low-noise signal conditioning circuit. The sensor is based on a tunneling magnetoresistive effect (TMR) and is placed on a copper bar carrying the high current under measurement. The circuit incorporates a voltage-to-current (v-i) driver to bias the MR element, as well as a lock-in amplifier for extracting the sensor signal with improved signal-to-noise ratio. The v-i driver is based on a full Wilson current mirror with emitter degeneration, which also compensates the sensor output at zero current (offset). A lock-in amplifier is added to extract small sensor signals from noise by synchronous detection, enabling precise measurement of sensor resistance variations. The v-i driver was analysed to evaluate the accuracy of the mirror current under realistic transistor mismatch conditions, and the boundary design conditions for its operation as a current mirror were established both by simulation and experimentally. The design and analysis of the proposed circuit are verified experimentally with a MR element submitted up to 125 A at 50 Hz, analysing immunity to interferences.

在本文中，一个磁阻（MR）传感器实现了一个单一的磁阻元件，而不是通常的桥配置，已开发用于交流（AC）电流测量，包括其低噪声信号调理电路的设计。该传感器是基于隧道磁阻效应（TMR），并放置在铜排承载被测量的大电流。该电路包含一个电压电流（v-i）驱动器来偏置磁流变元件，以及一个锁相放大器，用于提取具有改进信噪比的传感器信号。v-i驱动器是基于一个全威尔逊电流反射镜与发射极退化，这也补偿传感器输出在零电流（偏移）。锁相放大器通过同步检测从噪声中提取小传感器信号，从而精确测量传感器电阻的变化。分析了v-i驱动器在实际晶体管失配条件下反射镜电流的精度，并通过仿真和实验建立了其作为电流反射镜工作的边界设计条件。通过实验验证了所提出电路的设计和分析，并在50 Hz下提供了高达125 a的MR元件，分析了对干扰的抗扰性。

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引用次数: 0

An inverse-magnetostrictive force sensor with optimized bias magnetic field configuration and signal conditioning 一种具有优化偏置磁场结构和信号调理的反磁致伸缩力传感器

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-08 DOI: 10.1016/j.sna.2026.117473

Shaofeng Su, Yuhang Chen

In this study, we developed a force sensor utilizing the inverse magnetostrictive effect. The sensor architecture mainly comprised Galfenol alloy (Fe₈₃Ga₁₇) wires, neodymium iron boron (NdFeB) permanent magnets, and a Hall sensor. A theoretical model was constructed to characterize force and stiffness. Through finite element simulations, the optimal bias magnetic field was identified, and the dimensions and spatial arrangement of the permanent magnets were optimized. The optimal magnet configuration, combined with a meticulously designed second-order low-pass filter circuit, significantly improved the stability of the output signal while effectively suppressing fluctuations and noise. Systematic evaluations of the critical sensor parameters were conducted, demonstrating a force sensitivity of 33.4 mV/N, a resolution better than 0.1 N, a measurement range of 0–5 N, and rise/fall times of 12/18 ms. The feasibility of the sensor was verified for application in material stiffness characterization and surface topography measurement.

在这项研究中，我们开发了一种利用逆磁致伸缩效应的力传感器。传感器结构主要由Galfenol合金（Fe83Ga17）导线、钕铁硼（NdFeB）永磁体和霍尔传感器组成。建立了表征力和刚度的理论模型。通过有限元仿真，确定了最优偏置磁场，优化了永磁体的尺寸和空间布局。优化的磁体配置，结合精心设计的二阶低通滤波电路，显著提高了输出信号的稳定性，同时有效地抑制了波动和噪声。对关键传感器参数进行了系统评估，结果表明力灵敏度为33.4 mV/N，分辨率优于0.1 N，测量范围为0-5 N，上升/下降时间为12/18 ms。验证了该传感器在材料刚度表征和表面形貌测量中的可行性。

引用次数: 0

Magnetic helical micro/nanomachines: Recent advances in functionalization, driving control, and biomedical applications 磁性螺旋微/纳米机器：功能化、驱动控制和生物医学应用的最新进展

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-08 DOI: 10.1016/j.sna.2026.117468

Tongju Ma, Kun Li, Shuolei Wang, Zhongyi Qiu, Wenbo Xu, Wenguang Yang

Inspired by bacterial flagella, helical micro/nanomachines (H-MNMs)—a pioneering micro/nanorobotic design with decades of research—achieve controllable 3D movement by converting rotational motion into helical propulsion under external magnetic fields. Their environmental adaptability, cargo capacity, and non-damaging magnetic propulsion have made them a biomedical hotspot. While existing reviews summarize their fundamentals, this work offers three distinct perspectives: emphasizing "magnetic actuation-functionalization-preclinical translation" synergy over isolated points, highlighting 2020–2025 breakthroughs and establishing a cross-dimensional framework linking material, structure, manufacturing, control, and biomedical scenarios.

受细菌鞭毛的启发，螺旋微纳米机器（H-MNMs）是一种开创性的微纳米机器人设计，经过数十年的研究，在外部磁场下将旋转运动转化为螺旋推进，实现了可控的3D运动。它们的环境适应性、载货能力和非破坏性磁推进能力使它们成为生物医学的热点。虽然现有的综述总结了他们的基本原理，但这项工作提供了三个不同的视角：强调“磁驱动-功能化-临床前转化”在孤立点上的协同作用，突出2020-2025年的突破，建立连接材料，结构，制造，控制和生物医学场景的跨维度框架。

引用次数: 0

Phased array ultrasound transducer based on high-performance Mn-doped BS-PT ceramics for low-intensity focused ultrasound applications 基于高性能mn掺杂BS-PT陶瓷的相控阵超声换能器用于低强度聚焦超声

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-08 DOI: 10.1016/j.sna.2026.117471

Xi Tang , Xiaobing Li , Zhiyang Xu , Yili Hu , Shiyi Ou , Tiankun Xiong , Qian Chen , Changjiang Zhou , Jie Jiao , Jun Chen , Xiangyong Zhao

Low-Intensity Focused ultrasound (LIFUS) has emerged as a promising technique for non-invasive neuromodulation and targeted therapies due to its high spatial resolution and deep tissue penetration. To meet the requirements of stable performance under low acoustic intensity and thermal stress, a low-intensity focused ultrasound phased-array transducer was developed using the Mn-doped BiScO₃-PbTiO₃ (Mn:BS-PT) ceramics. It exhibits superior thermal and electrical stability, with a larger coercive field (∼18 kV/cm) and higher curie temperature (∼430°C) well above those of commercial PZT ceramics and PMN-PT crystals, enabling efficient operation under low acoustic power. A 16-element phased array transducer was fabricated and evaluated, achieving a focal depth of 20 mm and demonstrating excellent beam controllability. Acoustic field simulations confirmed effective beam focusing and electronic steering with a deflection angle up to ±11.5°. The spatial-peak temporal-average intensity (I_spta) reached approximately 0.31 W/cm², thereby supporting its suitability for LIFUS applications. These findings demonstrate the feasibility and effectiveness of Mn-doped BS-PT-based phased arrays for delivering focused ultrasound energy in musculoskeletal therapeutic applications.

低强度聚焦超声（Low-Intensity Focused ultrasound， LIFUS）由于其高空间分辨率和组织深度穿透性，在非侵入性神经调节和靶向治疗中已成为一种很有前景的技术。为了满足在低声强和热应力下性能稳定的要求，采用Mn掺杂的BiScO3-PbTiO3 （Mn:BS-PT）陶瓷，研制了一种低强度聚焦超声相控阵换能器。它具有优异的热稳定性和电稳定性，具有更大的矫顽力场（~ 18 kV/cm）和更高的居里温度（~ 430°C），远高于商用PZT陶瓷和PMN-PT晶体，能够在低声功率下高效工作。制作并评估了16元相控阵换能器，实现了20 mm的焦深，并表现出优异的光束可控性。声场模拟证实了有效的光束聚焦和电子转向，偏转角度可达±11.5°。空间-峰值-时间-平均强度（Ispta）达到约0.31 W/cm2，因此支持其适用于LIFUS应用。这些发现证明了mn掺杂bs - pt相控阵在肌肉骨骼治疗应用中提供聚焦超声能量的可行性和有效性。

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引用次数: 0

Highly sensitive and dual-selective gas sensing using WS2 nanosheets for NO2 and NH3 detection at low temperature 利用WS2纳米片在低温下进行NO2和NH3的高灵敏度和双选择性气敏检测

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2026-01-07 DOI: 10.1016/j.sna.2026.117464

Ho Huu Hau , Nguyen Viet Nhat , Luong Thi Theu , Phung Thi Viet Bac , Dinh Van An , Pham Van Thang , Hoang Si Hong , Nguyen Xuan Thai , Nguyen Duc Chien , Nguyen Van Duy , Nguyen Duc Hoa , Chu Manh Hung

For the first time, we report a dual-functional gas sensor based on highly sensitive WS₂ nanosheets. The WS₂ nanosheets were synthesized through a simple and environmentally friendly liquid-phase exfoliation (LPE) process using a water–ethanol solvent. The exfoliated nanosheets were 2–3 layers thick and exhibited p-type semiconducting behavior. The fabricated sensor showed excellent selectivity toward NO₂ at room temperature (RT, 25 °C) and NH₃ at 50 °C, with high responses of about 10 and 12–5 ppm NO₂ and 500 ppm NH₃, respectively. In addition, the sensor demonstrated outstanding short- and long-term stability, along with ultra-low detection limits of 4.7 ppb for NO₂ and 253.4 ppb for NH₃. These features are crucial for practical device applications. Density functional theory (DFT) calculations further revealed strong adsorption energy, charge transfer, and electronic structure modulation of WS₂ upon exposure to NO₂ and NH₃. Overall, these findings demonstrate that few-layer WS₂ nanosheets are highly promising for developing low-power, dual-selective, and scalable gas sensors for low-temperature applications.

本文首次报道了一种基于高灵敏度WS2纳米片的双功能气体传感器。以水-乙醇为溶剂，采用简单环保的液相剥离工艺合成了WS2纳米片。剥离后的纳米片厚度为2-3层，具有p型半导体特性。该传感器对室温NO2 （RT, 25℃）和50℃NH3具有良好的选择性，对NO2和NH3的响应分别为10和12-5 ppm和500 ppm。此外，该传感器表现出出色的短期和长期稳定性，同时对NO2的超低检测限为4.7 ppb，对NH3的超低检测限为253.4 ppb。这些特性对于实际设备应用至关重要。密度泛函理论（DFT）进一步揭示了WS2暴露于NO2和NH3时的强吸附能、电荷转移和电子结构调制。总的来说，这些发现表明，低层WS2纳米片在开发低功耗、双选择和可扩展的低温气体传感器方面非常有前途。

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引用次数: 0