Corrigendum to “Fabrication of highly porous platinum electrodes for micro-scale applications by pulsed electrodeposition and dealloying” [J. Power Sources 242 (2013) 255–263]

Zirconia oxygen sensors, in such applications as power plants and automobiles, generally utilize platinum electrodes for the catalytic reaction of dissociating O2 at the surface. The microstructure of the platinum electrode defines the resulting electrical response. The electrode must be porous enough to allow the oxygen to reach the zirconia surface while still remaining electrically continuous. At low sintering temperatures, the platinum is highly porous and fine grained. The platinum particles sinter together as the firing temperatures are increased. As the sintering temperatures are raised even further, the surface of the platinum begins to facet with lower energy surfaces. These microstructural changes can be seen in Figures 1 and 2, but the goal of the work is to characterize the microstructure by its fractal dimension and then relate the fractal dimension to the electrical response. The sensors were fabricated from zirconia powder stabilized in the cubic phase with 8 mol% percent yttria. Each substrate was sintered for 14 hours at 1200°C. The resulting zirconia pellets, 13mm in diameter and 2mm in thickness, were roughly 97 to 98 percent of theoretical density. The Engelhard #6082 platinum paste was applied to the zirconia disks after they were mechanically polished ( diamond). The electrodes were then sintered at temperatures ranging from 600°C to 1000°C. Each sensor was tested to determine the impedance response from 1Hz to 5,000Hz. These frequencies correspond to the electrode at the test temperature of 600°C.

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Stretchable micro-scale concentrator photovoltaic module with 15.4% efficiency for three-dimensional curved surfaces

Communications Materials ◽

10.1038/s43246-020-00106-x ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Daisuke Sato ◽

Taizo Masuda ◽

Kenji Araki ◽

Masafumi Yamaguchi ◽

Kenichi Okumura ◽

...

Keyword(s):

Concentration Ratio ◽

Power Conversion ◽

Three Dimensional ◽

Thin Film Solar Cells ◽

Photovoltaic Module ◽

Silicon Compound ◽

Curved Surfaces ◽

Power Sources ◽

Micro Scale ◽

Module Design

AbstractStretchable photovoltaics are emerging power sources for collapsible electronics, biomedical devices, and buildings and vehicles with curved surfaces. Development of stretchable photovoltaics are crucial to achieve rapid growth of the future photovoltaic market. However, owing to their rigidity, existing thin-film solar cells based predominantly on silicon, compound semiconductors, and perovskites are difficult to apply to 3D curved surfaces, which are potential real-world candidates. Herein, we present a stretchable micro-scale concentrator photovoltaic module with a geometrical concentration ratio of 3.5×. When perfectly fitted on a 3D curved surface with a sharp curvature, the prototype module achieves an outdoor power conversion efficiency of 15.4% and the daily generated electricity yield improves to a maximum of 190% relative to a non-concentration stretchable photovoltaic module. Thus, this module design enables high areal coverage on 3D curved surfaces, while generating a higher electricity yield in a limited installation area.

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Poisoning of Highly Porous Platinum Electrodes by Amino Acids and Tissue Fluid Constituents

ChemElectroChem ◽

10.1002/celc.201500215 ◽

2015 ◽

Vol 2 (11) ◽

pp. 1785-1793 ◽

Cited By ~ 9

Author(s):

Christian Köhler ◽

Lena Bleck ◽

Maxi Frei ◽

Roland Zengerle ◽

Sven Kerzenmacher

Keyword(s):

Amino Acids ◽

Tissue Fluid ◽

Platinum Electrodes ◽

Highly Porous

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Micro-scale fluid model for drying of highly porous particle aggregates

Computers & Chemical Engineering ◽

10.1016/j.compchemeng.2012.12.003 ◽

2013 ◽

Vol 52 ◽

pp. 46-54 ◽

Cited By ~ 7

Author(s):

Abdolreza Kharaghani ◽

Christoph Kirsch ◽

Thomas Metzger ◽

Evangelos Tsotsas

Keyword(s):

Fluid Model ◽

Porous Particle ◽

Micro Scale ◽

Particle Aggregates ◽

Highly Porous

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Highly Porous Platinum Electrodes for Dry Ear-EEG Measurements

10.20944/preprints202004.0260.v1 ◽

2020 ◽

Author(s):

Max Eickenscheidt ◽

Patrick Schäfer ◽

Yara Baslan ◽

Claudia Schwarz ◽

Thomas Stieglitz

Keyword(s):

Growth Form ◽

Silver Chloride ◽

Auditory Attention ◽

Platinum Electrodes ◽

Effective Surface Area ◽

Effective Surface ◽

Transmission Properties ◽

Silver Silver ◽

Silver Silver Chloride ◽

Highly Porous

The interest in dry EEG electrodes has increased in recent years and especially as everyday suitability earplugs for measuring drowsiness or focus of auditory attention. However, the challenge is still the need for a good electrode material, which is reliable and can be easily processed for highly personalized applications. Laser processing as used here is a fast and very precise method to produce personalized electrode configurations that meet the high requirements of in-ear EEG electrodes, for example. The arrangement of the electrodes on the very flexible and compressible mats allows an exact alignment of the electrodes to the ear mold and contributes to a high wearing comfort, as no edges or metal protrusions are present. For better transmission properties, an adapted coating process for surface enlargement of platinum electrodes is used, which allows easy control of the thickness and growth form of the porous layer. The porous platinum-copper alloy is chemically very stable, shows no exposed copper residues and enlarges the effective surface area by 40. In a proof-of-principle experiment, these porous platinum electrodes could be used to measure the Berger effect in a dry state using just one ear of a test person. Their signal-to-noise ration and frequency transfer function is comparable to gel-based silver/silver chloride electrodes.

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Highly Porous Platinum Electrodes for Dry Ear-EEG Measurements

Sensors ◽

10.3390/s20113176 ◽

2020 ◽

Vol 20 (11) ◽

pp. 3176 ◽

Cited By ~ 1

Author(s):

Max Eickenscheidt ◽

Patrick Schäfer ◽

Yara Baslan ◽

Claudia Schwarz ◽

Thomas Stieglitz

Keyword(s):

Silver Chloride ◽

Signal To Noise Ratio ◽

Auditory Attention ◽

Platinum Electrodes ◽

Effective Surface Area ◽

Effective Surface ◽

Transmission Properties ◽

Silver Silver ◽

Silver Silver Chloride ◽

Highly Porous

The interest in dry electroencephalography (EEG) electrodes has increased in recent years, especially as everyday suitability earplugs for measuring drowsiness or focus of auditory attention. However, the challenge is still the need for a good electrode material, which is reliable and can be easily processed for highly personalized applications. Laser processing, as used here, is a fast and very precise method to produce personalized electrode configurations that meet the high requirements of in-ear EEG electrodes. The arrangement of the electrodes on the flexible and compressible mats allows an exact alignment to the ear mold and contributes to high wearing comfort, as no edges or metal protrusions are present. For better transmission properties, an adapted coating process for surface enlargement of platinum electrodes is used, which can be controlled precisely. The resulting porous platinum-copper alloy is chemically very stable, shows no exposed copper residues, and enlarges the effective surface area by 40. In a proof-of-principle experiment, these porous platinum electrodes could be used to measure the Berger effect in a dry state using just one ear of a test person. Their signal-to-noise ratio and the frequency transfer function is comparable to gel-based silver/silver chloride electrodes.

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