Article
Chemistry, Multidisciplinary
Yimei Xie, Yongfa Cheng, Yanan Ma, Jian Wang, Junjie Zou, Han Wu, Yang Yue, Baowen Li, Yihua Gao, Xin Zhang, Ce-Wen Nan
Summary: A flexible piezoresistive sensor made of PEI fibrous network covered with MXene nanosheets is reported. It has ultrahigh sensitivity over a wide temperature range (-5℃ to 150℃), low detection limit, fast response time, and outstanding durability. The sensor can be applied to human-machine interaction and pressure distribution measurement.
Article
Optics
Shiqi Yu, Chunya Qian, Qi Zhou, Lujie Wang, Hui Xiao, Song Ye, Xuefeng Li
Summary: A fiber optic temperature sensor based on up-conversion luminescence (UCL) was proposed in this study, showing significant spectrum-temperature characteristics and high sensitivities in the temperature range of 80-373 K. The sensor also demonstrated good mechanical strength and system stability, with great potential for development in the aerospace field.
Article
Chemistry, Physical
Tingting Yu, Dongguang Zhang, Yali Wu, Shizhong Guo, Fan Lei, Yang Li, Jiayi Yang
Summary: This study presents a graphene foam pressure sensor based on fractal electrodes with high sensitivity and wide linear range, suitable for health monitoring and human motion measurement.
Article
Engineering, Electrical & Electronic
Ruimin Jie, Lingmei Ma, Xu Liu, Hongkun Zheng, Lang Jiang, Cheng Xu, Chen Zhu, Yunjiang Rao, Bo Liu
Summary: In this article, a chirped pulse interferometer (CPI) is proposed for vibration sensing in critical structures. The CPI is empowered by a pair of gold-coated optical fiber partial reflectors and can reliably detect vibrations from 1 Hz to 30 kHz at temperatures up to 600 degrees C. It outperforms a commercial accelerometer and a high-precision fiber Bragg grating (FBG) interrogator in terms of frequency response and signal-to-noise ratio.
IEEE SENSORS JOURNAL
(2023)
Article
Optics
Gang Li, Lanting Ji, Guoqiang Li, Qingquan Sun, Dexin Gao, Shanshan Zhao, Juan Su, Chi Wu
Summary: The sensor utilizes a fiber Bragg grating Fabry-Perot cavity combined with beat frequency interrogation, providing high-resolution and wide-range temperature measurement. With the introduction of a reference frequency, the sensor demonstrates good long-term stability. It is suitable for fields where resolving slight temperature changes is crucial.
Article
Chemistry, Analytical
Behnaz Jafari, Madhivanan Muthuvel, Gerardine G. Botte
Summary: A new electrochemical sensor using nickel as the working electrode has been developed for specific and quantitative detection of hydroxyl ions in solution, with a current proportional to the ion concentration and correlated to pH. The sensor shows promising stability and repeatability in measurements, with three linear calibration curves for different pH ranges.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2021)
Article
Optics
Guozhen Yao, Yimeng Yin, Yongqian Li, Haonan Yi
Summary: Optical fiber sensing technology, specifically the demodulation of fiber Bragg grating (FBG) sensors, is crucial for the accuracy and stability of sensing in the Internet of Things. The proposed composite gas cell demodulation scheme based on spectrum correction and data fusion has successfully improved the demodulation performance of FBG sensors in terms of accuracy and stability, with significant results shown in experiments.
Article
Chemistry, Physical
Jing Wang, Tianyi Dai, Yuchen Zhou, Amel Mohamed, Guoliang Yuan, Hongbing Jia
Summary: This study designed sensors based on oxidized sodium alginate/polyacrylamide/polydopamine-Ti3C2Tx/glycerol/water organohydrogels, which exhibited excellent mechanical properties, self-healing ability, and sensing stability. The sensors showed high sensitivity due to the combination of ionic and electron conduction, and could stably detect human movement under extreme conditions.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Chemistry, Physical
Ravina Swami, Ankur Shandilya, A. K. Shukla, P. Senthil Kumar, K. Sreenivas
Summary: Temperature sensing in the range (93-773 K) using luminescence intensity ratio method has been studied in rare earth ion modified La2-x-yErxYbyTi2O7 powders and ceramics. The optimised composition with (x = 0.025, y = 0.05) shows improved upconversion luminescence. The sintered ceramic is found useful for non-contact temperature sensing with a wider operating temperature range (243-1293 K) in comparison to calcined powders (163-863 K).
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Instruments & Instrumentation
Zhigang Gao, Hailiang Chen, Yuhui Feng, Sajid Ullah, Hongwei Li, Xili Jing, Shuguang Li
Summary: This work proposes a low-cost temperature sensor based on surface plasmon resonance (SPR) using optical fiber. The sensor is formed by splicing a short length of no-core fiber (NCF) with two multimode fibers (MMFs) and depositing a silver film on the NCF to excite SPR effect. It has a wide detection range and good reliability, making it valuable for applications in agricultural production and soil temperature monitoring.
INFRARED PHYSICS & TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Xiang Cheng, Jun Cai, Jiahua Xu, De Gong
Summary: A facile strategy to fabricate stretchable strain sensors based on Au/graphene composite films (AGCFs) was proposed, demonstrating high sensitivity, favorable linearity, fast response, excellent cycling stability, and great versatility. The sensors could achieve higher GF through pattern designing.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Engineering, Electrical & Electronic
Ademola A. A. Mustapha, Omar S. S. Hassan, Temesgen D. D. Ataro, Mohammed Saif Ur Rahman, Mohamed A. A. Abou-Khousa
Summary: This article introduces a fully characterized wide-range radio frequency-based contactless linear displacement sensor, which accurately measures displacement with a wide dynamic range and high measurement accuracy. The proposed sensor outperforms the traditional linear variable differential transformer (LVDT) displacement transducer in terms of overall measurement accuracy and offers a theoretical dynamic range suitable for a wide range of applications.
IEEE SENSORS JOURNAL
(2023)
Article
Optics
Ao Gao, Jingfu Ye, Chenxi Tu, Yi Liu, Shiliang Qu
Summary: This paper proposes a scheme called under-sampled length spectrum retrieval (ULSR) for fiber Fabry-Perot (F-P) cavity refractive index (RI) demodulation. Unlike the wavelength spectrum method, ULSR can detect physical quantities using only a monochromatic laser and photodetectors, eliminating the need for wideband lasers or expensive infrared spectrometers. By fabricating eight F-P cavities of different lengths to sample the cavity length spectrum, the RI of F-P cavity fillings can be demodulated using the obtained under-sampled length spectrum. The ULSR system achieves an index measurement accuracy of 1 x 10-4 in the glucose solution index range of 1.3294-1.3746 at a wavelength λ = 1.55μm. Higher accuracy and a wider range of index demodulation are expected with more than eight F-P cavities. The proposed scheme has the advantages of low system complexity, low cost, high reliability, high detecting accuracy, and wide detecting range, making it very promising for the wide application of F-P cavity sensors. Additionally, ULSR releases wavelength freedom, making it a strong candidate for multiplexed sensing based on wavelength division multiplexing.
Article
Optics
Qianjin Wang, Pengshuai Sun, Zhirong Zhang, Yongjun Cai, Wenbiao Huang, Tao Pang, Bian Wu, Hua Xia, Qiang Guo
Summary: The paper presents a method of optimized direct absorption spectroscopy for gas concentration detection, which can achieve fast response and calibration-free in a wide dynamic range. Experimental results demonstrate the linear consistency of the method at various concentrations, greatly improving accuracy and reliability.
Article
Engineering, Electrical & Electronic
Xueyang Liu, Chuanliang Li, Zhentao Wang, Yifeng Li, Jianqiu Huang, Huiyang Yu
Summary: This paper presents flexible pressure sensors based on 3D printing technology, with a sandwich structure design and a hollow prism structure pressure sensitive layer. Experimental synthesis of three kinds of flexible composite dielectrics demonstrated that the sensor with PDMS doping both BaTiO3 and CNTs showed the highest sensitivity, 1.3 times that of the reference sensor, indicating that fabricating composite dielectrics in this way has the potential to improve device performance.
IEEE SENSORS JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Vinicius G. Antunes, Carlos A. Figueroa, Fernando Alvarez
Summary: This paper reports on the competition between H2O (residual) and H-2 by site (defects) on the Si surface, created by Xe+ ion bombardment. X-ray photoelectron spectroscopy (XPS) was used to analyze the data, as hydrogen cannot be detected by XPS. The study found that the hydrogen passivation effect limits the formation of Si-OH and Si-O-Si bonds, and Xe+ ion bombardment diminishes the H-2 chemisorption energy barrier onto Si.
Article
Chemistry, Physical
Digvijay Singh, Felipe Cemin, Mawin J. M. Jimenez, Vinicius Antunes, Fernando Alvarez, Dmytro Orlov, Carlos A. Figueroa, Santosh S. Hosmani
Summary: This study investigates the high-temperature oxidation behavior of nanostructure surface layered AISI 304L stainless steel. The results show that the surface mechanical attrition treatment (SMAT) process can lead to the formation of a stable and protective oxide scale with better adhesion and higher density.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Ceramics
A. R. Zanatta, F. G. Echeverrigaray, F. Cemin, F. Alvarez
Summary: Future technological progress relies heavily on the development of advanced materials with new or improved properties. TixOyNz and TiO2 are two materials that perfectly meet these requirements, as their main chemical and structural properties can be customized to contribute to various applications in optics, electronics, catalysis, bactericides surfaces, and photovoltaics.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2022)
Article
Instruments & Instrumentation
Ricardo Javier Pena Roman, Yves Auad, Lucas Grasso, Lazaro A. Padilha, Fernando Alvarez, Ingrid David Barcelos, Mathieu Kociak, Luiz Fernando Zagonel
Summary: This paper presents a light collection/injection strategy based on an off-axis parabolic mirror collector for a low-temperature Scanning Tunneling Microscope (STM). The system allows for various spectroscopic techniques and demonstrates flexible and efficient light injection and collection capabilities on metallic surfaces and semiconducting samples.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Nanoscience & Nanotechnology
Carla D. Boeira, Felipe Cemin, Leonardo M. Leidens, Jennifer S. Weber, Alexandre F. Michels, Cesar Aguzzoli, Ricardo Serra, Manuel Evaristo, Filipe Fernandes, Fernando Alvarez, Albano Cavaleiro, Carlos A. Figueroa
Summary: This study analyzes the influence of base pressure on the adhesion of amorphous carbon (a-C) films on a ferrous alloy intermediated by a nanometric silicon interlayer. By quantifying the oxygen content and correlating it with the base pressure, a quantitative physicochemical model is proposed to explain the relationship between adhesion and oxygen content.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Fernando Graniero Echeverrigaray, Carlos Alejandro Figueroa, Antonio Ricardo Zanatta, Fernando Alvarez
Summary: In this paper, topographically asymmetric TiOx/TiSix metastable ultrathin films were successfully produced by controlling interface reactions through ion beam synthesis. The reactivity of oxygen and hydrogen species was found to be the dominating factor influencing the film growth. These functional metastable films show great potential for high-performance photonic and optoelectronic applications.
ADVANCED MATERIALS INTERFACES
(2022)
Article
Chemistry, Physical
Felipe Cemin, Leonardo Luis Artico, Vanessa Piroli, Jose Andres Yunes, Carlos Alejandro Figueroa, Fernando Alvarez
Summary: This study combines the concept of high-entropy designed materials with metallic glasses to develop a high-entropy metallic glass coating for biomedical applications. The coating exhibits amorphous structure, improved corrosion resistance, and enhanced biocompatibility. These properties make it a promising candidate for use as a biocoating on orthopedic implants.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Gustavo Lanza, Mawin J. Martinez Jimenez, Fernando Alvarez, Jaime Andres Perez-Taborda, Alba Avila
Summary: In this study, a method to fine-tune the valence states of gold nanoparticles (AuNPs) through annealing and ion bombardment was reported. XPS analysis showed that low-energy ion bombardment could dynamically adjust the valence states of gold from Au3+ and Au1+ to Au-0. Controlling the reduction in valence states is crucial for surface engineering and catalytic reaction control.
Article
Nanoscience & Nanotechnology
Leonardo M. Leidens, Alexandre F. Michels, Bruna L. Perotti, Fernando Alvarez, Antonio R. Zanatta, Carlos A. Figueroa
Summary: A study has revealed the nanofriction behavior of silicon-based materials, showing that the friction force increases during sliding. The experimental evaluation of hydrogenated amorphous silicon has demonstrated that the friction force recovers an intermediate value after separation and new contact, indicating the successive creation and breaking of bonds at the interface. This detailed experimental study has the potential to promote the broader nanoapplication of the material and suggest new devices based on its anomalous behavior.
ACS APPLIED NANO MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
A. R. Zanatta
Summary: The Raman spectrum of lithium niobate (LiNbO3) was investigated at various temperatures and laser spot sizes. The main phonon modes were analyzed in terms of peak position and linewidth, revealing contributions from anharmonic phonon-coupling and thermal lattice expansion processes. The A1(TO4) mode exhibited a peculiar behavior depending on the laser spot size, attributed to the congruent-photorefractive nature of LiNbO3 and changes in polarization geometry.
RESULTS IN PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
A. R. Zanatta
Summary: The investigation of the GeSn system reveals new properties related to metal-induced crystallization of amorphous Ge films. By varying the Sn concentration and annealing temperature, the Ge crystallization process can be controlled, resulting in cost-effective poly-crystalline Ge films. Raman spectroscopy confirms the influence of Sn in reducing the crystallization temperature and improving the quality of Ge crystallites.
MATERIALS CHEMISTRY AND PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Antonio Riul, Anerise de Barros, Gabriel Gaal, Maria L. Braunger, Mawin J. Jimenez, Carlos Avila-Avendano, Varlei Rodrigues, Monica Jung de Andrade, Manuel Quevedo-Lopez, Fernando Alvarez, Ray H. Baughman
Summary: Self-healing materials play a crucial role in the development of next-generation multifunctional wearables and IoT appliances. The layer-by-layer technique allows for homogeneous dispersion of materials on various matrices, while the addition of conductive fillers enables the creation of thin film composites with controlled conductivity and healing ability under ambient conditions. Achieving a delicate balance among electrical, mechanical, and structural characteristics is essential for the design of conductive self-healing composites. The application of these composites in a self-healing e-tongue demonstrates their potential for solving technological challenges.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
L. M. Leidens, D. Matte, G. L. Rech, J. E. Zorzi, A. F. Michels, F. Alvarez, C. A. Perottoni, C. A. Figueroa
Summary: This study proposes a desorption-based model to investigate the isotopic effect on phononic dissipation during friction behavior at the nanoscale. Contradictory conclusions were reported from previous experimental and theoretical approaches. The results show that even a minor surface coverage difference of 5% can have a significant impact on friction, which is supported by molecular dynamics simulations.
APPLIED SURFACE SCIENCE ADVANCES
(2022)