scholarly journals Formation and Characterization of Various ZnO/SiO2-Stacked Layers for Flexible Micro-Energy Harvesting Devices

2018 ◽  
Vol 8 (7) ◽  
pp. 1127 ◽  
Author(s):  
Chongsei Yoon ◽  
Buil Jeon ◽  
Giwan Yoon

In this paper, we present a study of various ZnO/SiO2-stacked thin film structures for flexible micro-energy harvesting devices. Two groups of micro-energy harvesting devices, SiO2/ZnO/SiO2 micro-energy generators (SZS-MGs) and ZnO/SiO2/ZnO micro-energy generators (ZSZ-MGs), were fabricated by stacking both SiO2 and ZnO thin films, and the resulting devices were characterized. With a particular interest in the fabrication of flexible devices, all the ZnO and SiO2 thin films were deposited on indium tin oxide (ITO)-coated polyethylene naphthalate (PEN) substrates using a radio frequency (RF) magnetron sputtering technique. The effects of the thickness and/or position of the SiO2 films on the device performance were investigated by observing the variations of output voltage in comparison with that of a control sample. As a result, compared to the ZnO single-layer device, all the ZSZ-MGs showed much better output voltages, while all the SZS-MG showed only slightly better output voltages. Among the ZSZ-MGs, the highest output voltages were obtained from the ZSZ-MGs where the SiO2 thin films were deposited using a deposition power of 150 W. Overall, the device performance seems to depend significantly on the position as well as the thickness of the SiO2 thin films in the ZnO/SiO2-stacked multilayer structures, in addition to the processing conditions.

Author(s):  
Chongsei Yoon ◽  
Buil Jeon ◽  
Giwan Yoon

In this paper, we present a study of various ZnO/SiO2-stacked thin film structures for flexible micro-energy harvesting devices. Two groups of micro-energy harvesting devices, SiO2/ZnO/SiO2 micro-energy generators (SZS-MGs) and ZnO/SiO2/ZnO micro-energy generators (ZSZ-MGs), were fabricated by stacking both SiO2 and ZnO thin films, and the resulting devices were characterized. With a particular interest in the fabrication of flexible devices, all the ZnO and SiO2 thin films were deposited on ITO-coated PEN substrates using an RF magnetron sputtering technique. The effects of the thickness and/or position of the SiO2 films on the device performance were investigated by observing the variations of output voltage in comparison with that of a control sample. As a result, compared to the ZnO single-layer device, all the ZSZ-MGs showed much better output voltages, while all the SZS-MG showed only slightly better output voltages. Among the ZSZ-MGs, the highest output voltages were obtained from the ZSZ-MGs where the SiO2 thin films were deposited using a deposition power of 150 W. Overall, the device performance seems to depend significantly on the position as well as the thickness of the SiO2 thin films in the ZnO/ SiO2-stacked multilayer structures, in addition to the processing conditions.


Energies ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2797 ◽  
Author(s):  
Chongsei Yoon ◽  
Buil Jeon ◽  
Giwan Yoon

In this paper, we present zinc oxide (ZnO)-based flexible harvesting devices employing commercially available, cost-effective thin aluminum (Al) foils as substrates and conductive bottom electrodes. From the device fabrication point of view, Al-foils have a relatively high melting point, allowing for device processing and annealing treatments at elevated temperatures, which flexible plastic substrate materials cannot sustain because of their relatively low melting temperatures. Moreover, Al-foil is a highly cost-effective, commercially available material. In this work, we fabricated and characterized various kinds of multilayered thin-film energy harvesting devices, employing Al-foils in order to verify their device performance. The fabricated devices exhibited peak-to-peak output voltages ranging from 0.025 V to 0.140 V. These results suggest that it is feasible to employ Al-foils to fabricate energy-efficient energy harvesting devices at relatively high temperatures. It is anticipated that with further process optimization and device integration, device performance can be further improved.


2012 ◽  
Vol 8 (6) ◽  
pp. 460-463 ◽  
Author(s):  
Shi-na Li ◽  
Rui-xin Ma ◽  
Liang-wei He ◽  
Yu-qin Xiao ◽  
Jun-gang Hou ◽  
...  

2007 ◽  
Vol 1044 ◽  
Author(s):  
Otto J. Gregory ◽  
Ximing Chen ◽  
Gustave C. Fralick ◽  
John Wrbanek

AbstractThermoelectric devices based on “n-type” oxide semiconductors and metal/oxide nanocomposites are being considered for high temperature thermocouples, heat flux sensors and energy harvesting devices. In terms of energy harvesting, preliminary 2D thermoelectric calculations indicated that enough electrical energy can be generated from the large thermal gradients that exist within a gas turbine engine to power active wireless devices. Several promising bi-ceramic junctions based on this concept were investigated in terms of their high temperature thermoelectric properties. The most promising bi-ceramic junction was based on indium tin oxide (ITO) and a NiCrCoAlY/alumina nanocomposite. The thermoelectric responses of these individual elements were evaluated relative to a platinum reference electrode. A maximum emf of 77 mV was achieved for a NiCrCoAlY/alumina nanocomposite/platinum thermocouple for an imposed temperature gradient of 1111 °C. The thermoelectric power for this couple was 78 μV/°C. When this NiCrCoAlY/alumina nanocomposite was combined with ITO to form a bi-ceramic junction, thermoelectric powers on the order of 700 μV/°C were obtained. A maximum electromotive force of 291mV was achieved for a hot junction temperature of 1100 °C. The thermoelectric response after repeated thermal cycling to 1200 °C was both repeatable and reproducible. The ITO was prepared in varying nitrogen, oxygen and argon partial pressures, which was used to control the charge carrier concentration, stability and thermoelectric response of the bi-ceramic junctions. The thermoelectric response decreased with increasing nitrogen partial pressure and increased with oxygen partial pressure in the plasma with the argon partial pressure constant. The relationship between the sputtering parameters and thermoelectric properties was investigated and the application of these bi-ceramic junctions as thermocouples and energy harvesting devices is discussed.


Nano Energy ◽  
2019 ◽  
Vol 55 ◽  
pp. 182-192 ◽  
Author(s):  
Sung Sik Won ◽  
Hosung Seo ◽  
Masami Kawahara ◽  
Sebastjan Glinsek ◽  
Jinkee Lee ◽  
...  

Author(s):  
Mohammad H. Malakooti ◽  
Florian Julé ◽  
Henry A. Sodano

Development of nanostructured devices for sensing, energy storage, actuating, and energy harvesting has attracted many researchers. The most common type of functional nanostructures is piezoelectric nanomaterials. Regardless of numerous studies in this area, there is a need for rapid fabrication of nanostructured devices, or simply functional nanocomposites. Here we present a simple, scalable fabrication technique for additive manufacturing of nanocomposite energy harvesting devices composed of barium titanate nanowires. Details on hydrothermal synthesis of barium titanate (BaTiO3) nanowires and printable inks, manufacturing process, and energy harvesting performance of the printed devices are presented here. The experimental results suggest that additive manufacturing of functional nanocomposites allows controlling the microstructures and enhancing device performance.


2000 ◽  
Vol 621 ◽  
Author(s):  
V. I. Dimitrova ◽  
F. Perjeru ◽  
Hong Chen ◽  
M. E. Kordesch

ABSTRACTThin films of Er doped AlN, ∼ 200 nm thick, were grown on indium tin oxide/aluminum titanium oxide/glass substrates using RF magnetron sputtering in a pure nitrogen atmosphere. To optically activate Er all films were subject to post-deposition annealing in flowing nitrogen atmosphere at atmospheric pressure at temperatures between 1023-1223 K for 10-60 minutes. The visible cathodoluminescence (CL) in the green was detected at both 11 K and 300K. The strongest CL peaks were observed at 558 nm and 537 nm (11 K), which correspond to the transitions from 4S3/2 and 2H11/2 to the 4I15/2 ground level. Electroluminescence (EL) studies of AlN:Er alternating-current thin-film electroluminescent (ACTFEL) devices were performed at 300 K. The turn-on voltage was found to be around 80-100 V for our ACTFEL devices. The intensity of the EL emission rapidly increases with the voltage increasing in the investigated range of 110-130 V.


1993 ◽  
Vol 318 ◽  
Author(s):  
L. H. Chang ◽  
Q. X. Jia ◽  
W. A. Anderson

ABSTRACTRF magnetron sputtering of BaTiO3 on (100) p-Si was performed to produce a high-quality BaTiO3/p-Si interface and BaTi03 insulator gates with high dielectric constant and low leakage current. Through different processing and device designs, different capacitor structures, including single layer amorphous, single layer polycrystalline and bi-layer amorphous on polycrystal-line, were investigated in this study. Raman spectroscopy showed the optical phonon modes of the BaTiO3 thin films with different structures. The structural properties of the films were characterized by X-ray diffraction. Using both the quasistatic and the high-frequency capacitance-voltage measurements, the interface-trap density was estimated at high 1011 eV−1 cm−2. The relative dielectric constant of the composite structure was controlled in a range from 30 to 130. The leakage current density was as low as 8×10−10 A/cm2 at a field intensity of (2±0.5)×105 V/cm. Breakdown voltage varied from 5x105 to 2×106 V/cm.


Sign in / Sign up

Export Citation Format

Share Document