An Electret/Hydrogel-Based Tactile Sensor Boosted by Micro-Patterned and Electrostatic Promoting Methods with Flexibility and Wide-Temperature Tolerance

With the rising demand for wearable, multifunctional, and flexible electronics, plenty of efforts aiming at wearable devices have been devoted to designing sensors with greater efficiency, wide environment tolerance, and good sustainability. Herein, a thin film of double-network ionic hydrogel with a solution replacement treatment method is fabricated, which not only possesses excellent stretchability (>1100%) and good transparency (>80%), but also maintains a wide application temperature range (−10~40 °C). Moreover, the hydrogel membrane further acts as both the flexible electrode and a triboelectric layer, with a larger friction area achieved through a micro-structure pattern method. Combining this with a corona-charged fluorinated ethylene propylene (FEP) film, an electret/hydrogel-based tactile sensor (EHTS) is designed and fabricated. The output performance of the EHTS is effectively boosted by 156.3% through the hybrid of triboelectric and electrostatic effects, which achieves the open-circuit peak voltage of 12.5 V, short-circuit current of 0.5 μA, and considerable power of 4.3 μW respectively, with a mentionable size of 10 mm × 10 mm × 0.9 mm. The EHTS also demonstrates a stable output characteristic within a wide range of temperature tolerance from −10 to approximately 40 °C and can be further integrated into a mask for human breath monitoring, which could provide for a reliable healthcare service during the COVID-19 pandemic. In general, the EHTS shows excellent potential in the fields of healthcare devices and wearable electronics.

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Numerical Investigation of the Cooling Temperature of the InGaP/InGaAs/Ge Subcells Under the Concentrated Illumination

Zeitschrift für Naturforschung A ◽

10.1515/zna-2019-0263 ◽

2020 ◽

Vol 75 (2) ◽

pp. 93-101

Author(s):

Kenza Djermane ◽

Syham Kadri ◽

Abdelhafid Habbab ◽

Elhouaria Bourbaba

Keyword(s):

Cooling System ◽

Short Circuit ◽

Short Circuit Current ◽

Incident Radiation ◽

Open Circuit ◽

Photovoltaic System ◽

Large Temperature ◽

High Concentration ◽

Cooling Temperature ◽

Wide Range

AbstractThe multijunction solar cells performances study is essential for the design of the high-concentration photovoltaic. These cells can operate over a wide range of the incident radiation flux and a large temperature range. These two parameters (concentration and temperature) degrade the cell and require a cooling system. In this article, we have studied numerically the cooling temperature of InGaP/lnGaAs/Ge subcells under the concentrated illumination. For this, we have presented the performance of each subcell as a function of the temperature and concentration sunlight. The different high concentrations ratios (1, 10, 100, and 1000 sun) have been conducted according to the dish-style concentration photovoltaic system for three temperature values T = 300, 500, and 800 K. The results show that under high concentrated light intensity conversion, the performances of these three subcells (efficiency, open-circuit voltage, short-circuit current, and fill factor) were decreased with increasing the temperature. The main objective of this study is to find the limit temperature of each subcell in order to introduce the cooling system. Thus, we can avoid the degradation of the tandem solar cell under the concentrated illumination.

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Equivalent-circuit Modeling of Microcrystalline Silicon pin Solar Cells prepared over a Wide Range of Absorber-layer Compositions

MRS Proceedings ◽

10.1557/proc-1245-a07-17 ◽

2010 ◽

Vol 1245 ◽

Author(s):

Steve Reynolds ◽

Vladimir Smirnov

Keyword(s):

Solar Cells ◽

Equivalent Circuit ◽

Volume Fraction ◽

Short Circuit ◽

Short Circuit Current ◽

Open Circuit ◽

Crystalline Region ◽

Photovoltaic Properties ◽

Wide Range ◽

Low Crystalline

AbstractAn equivalent-circuit electrical model is used to simulate the photovoltaic properties of mixed-phase thin-film silicon solar cells. Microcrystalline and amorphous phases are represented as separate parallel-connected photodiode equivalent circuits, scaled by assuming that the photodiode area is directly proportional to the volume fraction of each phase. A reasonable correspondence between experiment and simulation is obtained for short-circuit current and open-circuit voltage vs. volume fraction. However the large dip in fill-factor and reduced PV efficiency measured for cells prepared in the low-crystalline region is inadequately reproduced. It is concluded that poor PV performance in this region is not due solely to shunting by more highly-crystalline filaments, which supports the view that the low-crystalline material has transport properties inferior to either microcrystalline or amorphous silicon.

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The Reliability Analysis of PV Panels Installed in KP Region

International Journal of Engineering ◽

10.34259/ijew.20.710384389 ◽

2020 ◽

Vol 7 (10) ◽

pp. 384-389

Author(s):

Jawad Ahmad ◽

Keyword(s):

Short Circuit ◽

Equivalent Circuit Model ◽

Short Circuit Current ◽

Open Circuit ◽

Photovoltaic System ◽

Photovoltaic Module ◽

Pv System ◽

Peak Voltage ◽

Pv Module ◽

Term Performance

Reliability and long term performance of photovoltaic (PV) system is of vital importance in switching from conventional sources to sustainable one. Design, study and analysis of key components in a photovoltaic power system starting from generation of power to withstands number of climatic stresses and uninterrupted power supply plays a key role. One of the key elements in photovoltaic system is photovoltaic module. Also power generated in photovoltaic system is dependent on a source of energy that changes in every instant and with the passage of time during its operation .Hence it is paramount to build a long lasting photovoltaic module and analyze characteristics of the PV module under various conditions. This paper presents an efficient PV module based on PV equivalent circuit model using MATLAB/Simulink, and compared the simulated model results with manufacturer’s specifications like peak current, peak voltage, open circuit voltage and short circuit current .Also the performance of the module under variation of series resistance, irradiation, and temperature are analyzed. Data from five different areas across KP are noted and the results were Simulated and compared with the rated data.

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Carrier Transport and Recombination In A-SI:H P-I-N Solar Cells in Dark and Under Illumination

MRS Proceedings ◽

10.1557/proc-762-a3.4 ◽

2003 ◽

Vol 762 ◽

Cited By ~ 6

Author(s):

J. Deng ◽

J.M. Pearce ◽

V. Vlahos ◽

R.J. Koval ◽

R.W. Collins ◽

...

Keyword(s):

Solar Cells ◽

Carrier Transport ◽

Short Circuit ◽

Forward Bias ◽

Short Circuit Current ◽

Open Circuit ◽

Potential Barriers ◽

Carrier Lifetimes ◽

Wide Range

AbstractA study has been carried out on the forward bias dark current and the short circuit current -open circuit voltage characteristics of a-Si:H p-i-n solar cells over wide range of illumination intensities. Results are presented with superposition of these characteristics over extended current voltage regimes. This and the observed separation between these characteristics are consistent with the arguments presented based on first principle arguments. The conclusions drawn about the role of photo-generated carrier lifetimes, the densities of defects and the potential barriers in the i-layers adjacent to the n and p contacts are confirmed by numerical simulations. The key role of these potential barriers to the split in the characteristics offer new insight into both why the lack of superposition has been observed and the erroneous conclusions drawn about carrier transport for a-Si:H solar cells in the dark and under illumination.

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CdTe-Based Thin Film Solar Cells: Past, Present and Future

Energies ◽

10.3390/en14061684 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1684

Author(s):

Alessandro Romeo ◽

Elisa Artegiani

Keyword(s):

Thin Film ◽

Solar Cells ◽

Solar Cell ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Early Years ◽

Solar Cell Efficiency ◽

Cell Efficiency

CdTe is a very robust and chemically stable material and for this reason its related solar cell thin film photovoltaic technology is now the only thin film technology in the first 10 top producers in the world. CdTe has an optimum band gap for the Schockley-Queisser limit and could deliver very high efficiencies as single junction device of more than 32%, with an open circuit voltage of 1 V and a short circuit current density exceeding 30 mA/cm2. CdTe solar cells were introduced at the beginning of the 70s and they have been studied and implemented particularly in the last 30 years. The strong improvement in efficiency in the last 5 years was obtained by a new redesign of the CdTe solar cell device reaching a single solar cell efficiency of 22.1% and a module efficiency of 19%. In this paper we describe the fabrication process following the history of the solar cell as it was developed in the early years up to the latest development and changes. Moreover the paper also presents future possible alternative absorbers and discusses the only apparently controversial environmental impacts of this fantastic technology.

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GaInP/GaAs/poly-Si Multi-Junction Solar Cells by in Metal Balls Bonding

Crystals ◽

10.3390/cryst11070726 ◽

2021 ◽

Vol 11 (7) ◽

pp. 726

Author(s):

Ray-Hua Horng ◽

Yu-Cheng Kao ◽

Apoorva Sood ◽

Po-Liang Liu ◽

Wei-Cheng Wang ◽

...

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Low Temperature ◽

Triple Junction ◽

Short Circuit ◽

Short Circuit Current ◽

Open Circuit ◽

Metal Line ◽

Solar Simulator ◽

Junction Solar Cell

In this study, a mechanical stacking technique has been used to bond together the GaInP/GaAs and poly-silicon (Si) solar wafers. A GaInP/GaAs/poly-Si triple-junction solar cell has mechanically stacked using a low-temperature bonding process which involves micro metal In balls on a metal line using a high-optical-transmission spin-coated glue material. Current–voltage measurements of the GaInP/GaAs/poly-Si triple-junction solar cells have carried out at room temperature both in the dark and under 1 sun with 100 mW/cm2 power density using a solar simulator. The GaInP/GaAs/poly-Si triple-junction solar cell has reached an efficiency of 24.5% with an open-circuit voltage of 2.68 V, a short-circuit current density of 12.39 mA/cm2, and a fill-factor of 73.8%. This study demonstrates a great potential for the low-temperature micro-metal-ball mechanical stacking technique to achieve high conversion efficiency for solar cells with three or more junctions.

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Photocurrent density and electrical properties of Bi0.5Na0.5TiO3-BaNi0.5Nb0.5O3 ceramics

Journal of Advanced Ceramics ◽

10.1007/s40145-021-0497-7 ◽

2021 ◽

Author(s):

Mingqiang Zhong ◽

Qin Feng ◽

Changlai Yuan ◽

Xiao Liu ◽

Baohua Zhu ◽

...

Keyword(s):

Electrical Properties ◽

Photovoltaic Effect ◽

Short Circuit ◽

Short Circuit Current ◽

Photocurrent Density ◽

Open Circuit ◽

Light Conditions ◽

X Ray Diffraction ◽

Solid State Method ◽

X Ray

AbstractIn this work, the (1−x)Bi0.5Na0.5TiO3-xBaNi0.5Nb0.5O3 (BNT-BNN; 0.00 ⩽ x ⩽ 0.20) ceramics were prepared via a high-temperature solid-state method. The crystalline structures, photovoltaic effect, and electrical properties of the ceramics were investigated. According to X-ray diffraction, the system shows a single perovskite structure. The samples show the normal ferroelectric loops. With the increase of BNN content, the remnant polarization (Pr) and coercive field (Ec) decrease gradually. The optical band gap of the samples narrows from 3.10 to 2.27 eV. The conductive species of grains and grain boundaries in the ceramics are ascribed to the double ionized oxygen vacancies. The open-circuit voltage (Voc) of ∼15.7 V and short-circuit current (Jsc) of ∼1450 nA/cm2 are obtained in the 0.95BNT-0.05BNN ceramic under 1 sun illumination (AM1.5G, 100 mW/cm2). A larger Voc of 23 V and a higher Jsc of 5500 nA/cm2 are achieved at the poling field of 60 kV/cm under the same light conditions. The study shows this system has great application prospects in the photovoltaic field.

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Ultrathin Cu(In,Ga)Se2 Solar Cells with Ag/AlOx Passivating Back Reflector

Energies ◽

10.3390/en14144268 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4268

Author(s):

Jessica de Wild ◽

Gizem Birant ◽

Guy Brammertz ◽

Marc Meuris ◽

Jef Poortmans ◽

...

Keyword(s):

Surface Roughness ◽

Solar Cells ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Electron Microscopic ◽

Current Increase ◽

Time Resolved ◽

Cigs Solar Cells

Ultrathin Cu(In,Ga)Se2 (CIGS) absorber layers of 550 nm were grown on Ag/AlOx stacks. The addition of the stack resulted in solar cells with improved fill factor, open circuit voltage and short circuit current density. The efficiency was increased from 7% to almost 12%. Photoluminescence (PL) and time resolved PL were improved, which was attributed to the passivating properties of AlOx. A current increase of almost 2 mA/cm2 was measured, due to increased light scattering and surface roughness. With time of flight—secondary ion mass spectroscopy, the elemental profiles were measured. It was found that the Ag is incorporated through the whole CIGS layer. Secondary electron microscopic images of the Mo back revealed residuals of the Ag/AlOx stack, which was confirmed by energy dispersive X-ray spectroscopy measurements. It is assumed to induce the increased surface roughness and scattering properties. At the front, large stains are visible for the cells with the Ag/AlOx back contact. An ammonia sulfide etching step was therefore applied on the bare absorber improving the efficiency further to 11.7%. It shows the potential of utilizing an Ag/AlOx stack at the back to improve both electrical and optical properties of ultrathin CIGS solar cells.

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Enhancement of the performance of CdS/CdTe heterojunction solar cell using TiO2/ZnO bi-layer ARC and V2O5 BSF layers: A simulation approach

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200213 ◽

2020 ◽

Vol 92 (2) ◽

pp. 20901

Author(s):

Abdul Kuddus ◽

Md. Ferdous Rahman ◽

Jaker Hossain ◽

Abu Bakar Md. Ismail

Keyword(s):

Solar Cell ◽

Short Circuit ◽

Photovoltaic Performance ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Heterojunction Solar Cell ◽

Back Surface ◽

Heterojunction Solar Cells

This article presents the role of Bi-layer anti-reflection coating (ARC) of TiO2/ZnO and back surface field (BSF) of V2O5 for improving the photovoltaic performance of Cadmium Sulfide (CdS) and Cadmium Telluride (CdTe) based heterojunction solar cells (HJSCs). The simulation was performed at different concentrations, thickness, defect densities of each active materials and working temperatures to optimize the most excellent structure and working conditions for achieving the highest cell performance using obtained optical and electrical parameters value from the experimental investigation on spin-coated CdS, CdTe, ZnO, TiO2 and V2O5 thin films deposited on the glass substrate. The simulation results reveal that the designed CdS/CdTe based heterojunction cell offers the highest efficiency, η of ∼25% with an enhanced open-circuit voltage, Voc of 0.811 V, short circuit current density, Jsc of 38.51 mA cm−2, fill factor, FF of 80% with bi-layer ARC and BSF. Moreover, it appears that the TiO2/ZnO bi-layer ARC, as well as ETL and V2O5 as BSF, could be highly promising materials of choice for CdS/CdTe based heterojunction solar cell.

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