Browsing by Author "Yan, Yongke"

Now showing 1 - 14 of 14
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    3D printed graphene-based self-powered strain sensors for smart tires in autonomous vehicles
    Maurya, Deepam; Khaleghian, Seyedmeysam; Sriramdas, Rammohan; Kumar, Prashant; Kishore, Ravi Anant; Kang, Min-Gyu; Kumar, Vireshwar; Song, Hyun-Cheol; Lee, Seul-Yi; Yan, Yongke; Park, Jung-Min (Jerry); Taheri, Saied; Priya, Shashank (2020-10-26)
    The transition of autonomous vehicles into fleets requires an advanced control system design that relies on continuous feedback from the tires. Smart tires enable continuous monitoring of dynamic parameters by combining strain sensing with traditional tire functions. Here, we provide breakthrough in this direction by demonstrating tire-integrated system that combines direct mask-less 3D printed strain gauges, flexible piezoelectric energy harvester for powering the sensors and secure wireless data transfer electronics, and machine learning for predictive data analysis. Ink of graphene based material was designed to directly print strain sensor for measuring tire-road interactions under varying driving speeds, normal load, and tire pressure. A secure wireless data transfer hardware powered by a piezoelectric patch is implemented to demonstrate self-powered sensing and wireless communication capability. Combined, this study significantly advances the design and fabrication of cost-effective smart tires by demonstrating practical self-powered wireless strain sensing capability. Designing efficient sensors for smart tires for autonomous vehicles remains a challenge. Here, the authors present a tire-integrated system that combines direct mask-less 3D printed strain gauges, flexible piezoelectric energy harvester for powering the sensors and secure wireless data transfer electronics, and machine learning for predictive data analysis.
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    Colossal tunability in high frequency magnetoelectric voltage tunable inductors
    Yan, Yongke; Geng, Liwei D.; Tan, Yaohua; Ma, Jianhua; Zhang, Lujie; Sanghadasa, Mohan; Ngo, Khai D. T.; Ghosh, Avik W.; Wang, Yu U.; Priya, Shashank (2018-11-27)
    The electrical modulation of magnetization through the magnetoelectric effect provides a great opportunity for developing a new generation of tunable electrical components. Magnetoelectric voltage tunable inductors (VTIs) are designed to maximize the electric field control of permeability. In order to meet the need for power electronics, VTIs operating at high frequency with large tunability and low loss are required. Here we demonstrate magnetoelectric VTIs that exhibit remarkable high inductance tunability of over 750% up to 10 MHz, completely covering the frequency range of state-of-the-art power electronics. This breakthrough is achieved based on a concept of magnetocrystalline anisotropy (MCA) cancellation, predicted in a solid solution of nickel ferrite and cobalt ferrite through first-principles calculations. Phase field model simulations are employed to observe the domain-level strain-mediated coupling between magnetization and polarization. The model reveals small MCA facilitates the magnetic domain rotation, resulting in larger permeability sensitivity and inductance tunability.
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    Compositionally Graded Multilayer Ceramic Capacitors
    Song, Hyun-Cheol; Zhou, Jie E.; Maurya, Deepam; Yan, Yongke; Wang, Yu U.; Priya, Shashank (Springer Nature, 2017-09-27)
    Multilayer ceramic capacitors (MLCC) are widely used in consumer electronics. Here, we provide a transformative method for achieving high dielectric response and tunability over a wide temperature range through design of compositionally graded multilayer (CGML) architecture. Compositionally graded MLCCs were found to exhibit enhanced dielectric tunability (70%) along with small dielectric losses (< 2.5%) over the required temperature ranges specified in the standard industrial classifications. The compositional grading resulted in generation of internal bias field which enhanced the tunability due to increased nonlinearity. The electric field tunability of MLCCs provides an important avenue for design of miniature filters and power converters.
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    Correlation between tunability and anisotropy in magnetoelectric voltage tunable inductor (VTI)
    Yan, Yongke; Geng, Liwei D.; Zhang, Lujie; Gao, Xiangyu; Gollapudi, Sreenivasulu; Song, Hyun-Cheol; Dong, Shuxiang; Sanghadasa, Mohan; Ngo, Khai D. T.; Wang, Yu U.; Priya, Shashank (Springer Nature, 2017-11-22)
    Electric field modulation of magnetic properties via magnetoelectric coupling in composite materials is of fundamental and technological importance for realizing tunable energy efficient electronics. Here we provide foundational analysis on magnetoelectric voltage tunable inductor (VTI) that exhibits extremely large inductance tunability of up to 1150% under moderate electric fields. This field dependence of inductance arises from the change of permeability, which correlates with the stress dependence of magnetic anisotropy. Through combination of analytical models that were validated by experimental results, comprehensive understanding of various anisotropies on the tunability of VTI is provided. Results indicate that inclusion of magnetic materials with low magnetocrystalline anisotropy is one of the most effective ways to achieve high VTI tunability. This study opens pathway towards design of tunable circuit components that exhibit field-dependent electronic behavior.
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    Electromechanical behavior of 001 -textured Pb(Mg1/3Nb2/3)O-3-PbTiO3 ceramics
    Yan, Yongke; Wang, Yu. U.; Priya, Shashank (AIP Publishing, 2012-05-01)
    [001]-textured Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMN-PT) ceramics were synthesized by using templated grain growth method. Significantly high [001] texture degree corresponding to 0.98 Lotgering factor was achieved at 1 vol. % BaTiO3 template. Electromechanical properties for [001]-textured PMN-PT ceramics with 1 vol. % BaTiO3 were found to be d(33) = 1000 pC/N, d(31) = 371 pC/N, epsilon(r) 2591, and tan delta = similar to 0.6%. Elastoelectric composite based modeling results showed that higher volume fraction of template reduces the overall dielectric constant and thus has adverse effect on the piezoelectric response. Clamping effect was modeled by deriving the changes in free energy as a function of applied electric field and microstructural boundary condition. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4712563]
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    Giant energy density in 001 -textured Pb(Mg1/3Nb2/3)O-3-PbZrO3-PbTiO3 piezoelectric ceramics
    Yan, Yongke; Cho, Kyung-Hoon; Maurya, Deepam; Kumar, Amit; Kalinin, Sergei; Khachaturyan, Armen G.; Priya, Shashank (AIP Publishing, 2013-01-01)
    Pb(Zr,Ti)O-3 (PZT) based compositions have been challenging to texture or grow in a single crystal form due to the incongruent melting point of ZrO2. Here we demonstrate the method for achieving 90% textured PZT-based ceramics and further show that it can provide highest known energy density in piezoelectric materials through enhancement of piezoelectric charge and voltage coefficients (d and g). Our method provides more than similar to 5x increase in the ratio d(textured)/d(random). A giant magnitude of d.g coefficient with value of 59 000 x 10(-15) m(2) N-1 (comparable to that of the single crystal counterpart and 359% higher than that of the best commercial compositions) was obtained. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4789854]
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    Giant piezoelectric voltage coefficient in grain-oriented modified PbTiO3 material
    Yan, Yongke; Zhou, Jie E.; Maurya, Deepam; Wang, Yu U.; Priya, Shashank (Springer Nature, 2016-10-11)
    A rapid surge in the research on piezoelectric sensors is occurring with the arrival of the Internet of Things. Single-phase oxide piezoelectric materials with giant piezoelectric voltage coefficient (g, induced voltage under applied stress) and high Curie temperature (T-c) are crucial towards providing desired performance for sensing, especially under harsh environmental conditions. Here, we report a grain-oriented (with 95% <001> texture) modified PbTiO3 ceramic that has a high T-c (364 degrees C) and an extremely large g(33) (115 x 10(-3) Vm N-1) in comparison with other known single-phase oxide materials. Our results reveal that self-polarization due to grain orientation along the spontaneous polarization direction plays an important role in achieving large piezoelectric response in a domain motion-confined material. The phase field simulations confirm that the large piezoelectric voltage coefficient g(33) originates from maximized piezoelectric strain coefficient d(33) and minimized dielectric permittivity epsilon(33) in [001]-textured PbTiO3 ceramics where domain wall motions are absent.
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    Giant self-biased magnetoelectric coupling in co-fired textured layered composites
    Yan, Yongke; Zhou, Yuan; Priya, Shashank (AIP Publishing, 2013-02-01)
    Co-fired magnetostrictive/piezoelectric/magnetostrictive laminate structure with silver inner electrode was synthesized and characterized. We demonstrate integration of textured piezoelectric microstructure with the cost-effective low-temperature co-fired layered structure to achieve strong magnetoelectric coupling. Using the co-fired composite, a strategy was developed based upon the hysteretic response of nickel-copper-zinc ferrite magnetostrictive materials to achieve peak magnetoelectric response at zero DC bias, referred as self-biased magnetoelectric response. Fundamental understanding of self-bias phenomenon in composites with single phase magnetic material was investigated by quantifying the magnetization and piezomagnetic changes with applied DC field. We delineate the contribution arising from the interfacial strain and inherent magnetic hysteretic behavior of copper modified nickel-zinc ferrite towards self-bias response. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4791685]
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    Giant strain with ultra-low hysteresis and high temperature stability in grain oriented lead-free K0.5Bi0.5TiO3-BaTiO3-Na0.5Bi0.5TiO3 piezoelectric materials
    Maurya, Deepam; Zhou, Yuan; Wang, Yaojin; Yan, Yongke; Li, Jiefang; Viehland, Dwight D.; Priya, Shashank (Springer Nature, 2015-02-26)
    We synthesized grain-oriented lead-free piezoelectric materials in (K0.5Bi0.5TiO3-BaTiO3-xNa(0.5)Bi(0.5)TiO(3) (KBT-BT-NBT) system with high degree of texturing along the [001]c (c-cubic) crystallographic orientation. We demonstrate giant field induced strain (similar to 0.48%) with an ultra-low hysteresis along with enhanced piezoelectric response (d(33) similar to 190pC/N) and high temperature stability (similar to 160 degrees C). Transmission electron microscopy (TEM) and piezoresponse force microscopy (PFM) results demonstrate smaller size highly ordered domain structure in grain-oriented specimen relative to the conventional polycrystalline ceramics. The grain oriented specimens exhibited a high degree of non-180 degrees domain switching, in comparison to the randomly axed ones. These results indicate the effective solution to the lead-free piezoelectric materials.
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    Low-temperature co-firing of multilayer textured piezoelectric ceramics with inner electrodes
    (United States Patent and Trademark Office, 2019-03-05)
    Textured PMN-PZT fabricated by templated grain growth (TGG) method has a piezoelectric coefficient (d) of 3 to 5 times that of its random counterpart. By combining this TGG method with low-temperature co-firing ceramics (LTCC) techniques, co-fired multilayer textured piezoelectric ceramic materials with inner electrodes were produced at a temperature as low as 925° C., which silver could be used. Trilayer PMN-PZT ceramics prepared by this method show a strain increase of 2.5 times, a driving voltage decrease of 3 times, and an equivalent piezoelectric coefficient (d*) improvement of 10 to 15 times that of conventional random ceramic counterparts. Further, a co-fired magnetostrictive/piezoelectric/magnetostrictive laminate structure with silver inner electrode was also synthesized. The integration of textured piezoelectric microstructure with the cost-effective low-temperature co-fired layered structure achieves strong magnetoelectric coupling. These new materials have promising applications including as actuators, ultrasonic transducers, and use in energy harvesters.
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    Phase transition and temperature stability of piezoelectric properties in Mn-modified Pb(Mg1/3Nb2/3)O-3-PbZrO3-PbTiO3 ceramics
    Yan, Yongke; Kumar, Amit; Correa, Margarita; Cho, Kyung-Hoon; Katiyar, Ram S.; Priya, Shashank (AIP Publishing, 2012-04-01)
    This study investigates the effect of two different Mn modifiers [MnO2 and Pb(Mn1/3Nb2/3)O-3(PMnN)] on the of phase transitions in Pb(Mg1/3Nb2/3)O-3-PbZrO3-PbTiO3 ceramics. The temperature dependence of polarization derived from measured pyroelectric current indicated change in nature of phase transition with MnO2 doping. This phenomenon was supported by the temperature evolution of the linear softening of low lying hard lattice mode as revealed by Raman analysis. The grain size was found to increase with MnO2 doping (5X) while decrease with PMnN modification (0.5X). Interestingly, the piezoelectric constant of MnO2 modified composition showed negligible degradation (<1%) even after heat treatment very close to the ferroelectric-paraelectric transition temperature. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3703124]
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    Piezoelectric properties and temperature stability of Mn-doped Pb(Mg1/3Nb2/3)-PbZrO3-PbTiO3 textured ceramics
    Yan, Yongke; Cho, Kyung-Hoon; Priya, Shashank (AIP Publishing, 2012-03-01)
    In this letter, we report the electromechanical properties of textured 0.4Pb(Mg1/3Nb2/3) O-3-0.25PbZrO(3)-0.35PbTiO(3) (PMN-PZT) composition which has relatively high rhombohedral to tetragonal (R-T) transition temperature (TR-T of 160 degrees C) and Curie temperature (T-C of 234 degrees C) and explore the effect of Mn-doping on this composition. It was found that MnO2-doped textured PMN-PZT ceramics with 5 vol.% BaTiO3 template (T-5BT) exhibited inferior temperature stability. The coupling factor (k(31)) of T-5BT ceramic started to degrade from 75 degrees C while the random counterpart showed a very stable tendency up to 180 degrees C. This degradation was associated with the "interface region" formed in the vicinity of BT template. MnO2 doped PMN-PZT ceramics textured with 3 vol.% BT and subsequently poled at 140 degrees C (T-3BT140) exhibited very stable and high k(31) (>0.53) in a wide temperature range from room temperature to 130 degrees C through reduction in the interface region volume. Further, the T-3BT140 ceramic exhibited excellent hard and soft combinatory piezoelectric properties of d(33) = 720 pC/N, k(31) = 0.53, Q(m) = 403, delta = 0.3% which are very promising for high power and magnetoelectric applications. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3698157]
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    Thermal conductivity of self-assembled nano-structured ZnO bulk ceramics
    Zhao, Yu; Yan, Yongke; Kumar, Ashok; Wang, Hsin; Porter, Wallace D.; Priya, Shashank (American Institute of Physics, 2012-08-01)
    In this study, we describe the changes in thermal conductivity behavior of ZnO-Al micro- and nano-two-phase self-assembled composites with varying grain sizes. The reduction in thermal conductivity values of micro-composites was limited to similar to 15% for ZnO-4% Al. However, nano-composites exhibited large reduction, by a factor of about three, due to uniform distribution of nano-precipitates (ZnAl2O4) and large grain boundary area. Interestingly, the micro-composites revealed continuous decrease in thermal conductivity with increase in Al substitution while the nano-composites exhibited the lowest magnitudes for 2% Al concentration. Raman spectra indicated that phonon confinement in ZnO-Al nano-composites causes drastic decrease in the value of thermal conductivity. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4745034]
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    Ultrahigh Durability Perovskite Solar Cells
    Wu, Congcong; Wang, Kai; Feng, Xu; Jiang, Yuanyuan; Yang, Dong; Hou, Yuchen; Yan, Yongke; Sanghadasa, Mohan; Priya, Shashank (American Chemical Society, 2019-01-29)
    Unprecedented conversion efficiency has been demonstrated for perovskite solar cells (PSCs), however, their stability and reliability continue to be challenge. Here, an effective and practical method is demonstrated to overcome the device stability issues in PSCs. A CF4 plasma treatment method is developed that results in the formation of a robust C–Fx layer covering the PSC device, thereby, imparting protection during the operation of solar cell. PSCs exposed to fluorination process showed excellent stability against water, light, and oxygen, displaying relatively no noticeable degradation after being dipped into water for considerable time period. The fluorination process did not have any impact on the morphology and electrical property of the top Spiro-OMeTAD layer, resulting in a conversion efficiency of 18.7%, which is identical to that of the pristine PSC. Under the continuous Xe lamp (AM 1.5G, 1 sun) illumination in ambient air for 100 h, the fluorinated PSCs demonstrated 70% of initial conversion efficiency, which is 4000% higher than that of the pristine PSC devices. We believe this breakthrough will have significant impact on the transition of PSCs into real world applications.