Matej Jergel - Academia.edu (original) (raw)
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Papers by Matej Jergel
Physical Chemistry Chemical Physics
We show that small π-conjugated molecules adopt a lying-down orientation when deposited on few-la... more We show that small π-conjugated molecules adopt a lying-down orientation when deposited on few-layer MoS2 with horizontally oriented layers. In contrast, for vertically aligned MoS2 layers, DIP molecules are arranged in a standing-up manner.
Physical Chemistry Chemical Physics
The oxidation of MoS2 with a simultaneous decrease of MoS2 content.
The International Journal of Advanced Manufacturing Technology
Sustainable Energy Technologies and Assessments, 2016
The waste heat of high-power light emitting diodes (LEDs) is well localized and can be efficientl... more The waste heat of high-power light emitting diodes (LEDs) is well localized and can be efficiently harvested in contrast to incandescent or fluorescent light sources. Compact thin film thermoelectric generators can accumulate the high-density heat flux from the LED chip and convert it into usable electrical power. We designed and analyzed a thermal management setup with high power LED and embedded thin film thermoelectric generators. The available thermal gradient of approximately 50 K allows conversion of the LED waste heat with an overall efficiency of 1%. We present an application of the active cooling powered by the harvested waste heat. The compact flat shape of the thin film thermoelectric generators allows an instant upgrade of the existing LED-based luminaries available on the market.
Thin Solid Films, 2016
The strain-resistance transduction of commercially available In 2 O 3 /Au/Ag layered films suppor... more The strain-resistance transduction of commercially available In 2 O 3 /Au/Ag layered films supported by polyethyl-ene terephthalate (PET) foil was studied. A colossal gauge factor as high as about 60,000 was observed upon a strain of 1%. Such ultra-high response is presumably owing to conductivity derived from the tunnelling current across cracks formed in the strained In 2 O 3 film; the cracks – as visualized by scanning electron microscopy – are oriented perpendicularly to the strain vector and are noted for their uniform width across the sample. It is further demonstrated that the standardly defined gauge factor is incommensurate for strain sensors with transduc-tion based on the tunnelling current and a redefined formula for the gauge factor was proposed.
Mater Sci Eng a Struct Mater, 1997
Acta Physica Polonica A, 2009
Sensors and Actuators A: Physical, 2016
DESCRIPTION SAXS, nanoparticle monolayer, strain sensor
Journal of Raman Spectroscopy, 2015
We report on a reference-free Raman spectroscopy method for a precise thickness determination of ... more We report on a reference-free Raman spectroscopy method for a precise thickness determination of the multilayered graphene oxide flakes. The method is based on the normalization of the total integral intensity of D and G Raman bands to the integral intensity of the second-order optical phonon peak of the silicon substrate in the Raman spectrum. The normalization provides discrete ratio values corresponding to the number of graphene oxide layers in the respective flakes with the intensity linearly increasing with the number of layers. This provides a fast and robust determination of the thickness of graphene oxide flakes in terms of the layer number up to high values. A comparison with conventional spectrally resolved reflectivity mapping shows similar sensitivity, while selectivity to particular functional chemical groups is a bonus of the Raman-based method. Copyright
Acta Crystallographica Section A Foundations and Advances, 2014
Self-assembled metal oxide nanoparticle layers have attracted much attention recently due to pote... more Self-assembled metal oxide nanoparticle layers have attracted much attention recently due to potential applications in sensors. Here we report on a UV/ozone-driven re-assembly and oxidation of a self-assembled silver nanoparticle bilayer deposited by a modified Langmuir-Schaefer technique that was probed in-situ by simultaneous measurements of the small- and wide-angle X-ray scattering at grazing incidence (GISAXS, GIWAXS). The experiments were performed at BL23A endstation of NSRRC, Taiwan. Four distinct stages of the system response to the UV/ozone treatment were identified. In the first stage 0-120 s, a gradual extinction of Bragg rods and the nanoparticle short-range order due to a gradual surfactant removal is observed in GISAXS that is connected with an array densification and order improvement obeying the paracrystal model in the shrinking self-assembled regions. In the second stage 120-360 s, the original self-assembly goes to a total extinction while the integral intensity ...
Physical Chemistry Chemical Physics
We show that small π-conjugated molecules adopt a lying-down orientation when deposited on few-la... more We show that small π-conjugated molecules adopt a lying-down orientation when deposited on few-layer MoS2 with horizontally oriented layers. In contrast, for vertically aligned MoS2 layers, DIP molecules are arranged in a standing-up manner.
Physical Chemistry Chemical Physics
The oxidation of MoS2 with a simultaneous decrease of MoS2 content.
The International Journal of Advanced Manufacturing Technology
Sustainable Energy Technologies and Assessments, 2016
The waste heat of high-power light emitting diodes (LEDs) is well localized and can be efficientl... more The waste heat of high-power light emitting diodes (LEDs) is well localized and can be efficiently harvested in contrast to incandescent or fluorescent light sources. Compact thin film thermoelectric generators can accumulate the high-density heat flux from the LED chip and convert it into usable electrical power. We designed and analyzed a thermal management setup with high power LED and embedded thin film thermoelectric generators. The available thermal gradient of approximately 50 K allows conversion of the LED waste heat with an overall efficiency of 1%. We present an application of the active cooling powered by the harvested waste heat. The compact flat shape of the thin film thermoelectric generators allows an instant upgrade of the existing LED-based luminaries available on the market.
Thin Solid Films, 2016
The strain-resistance transduction of commercially available In 2 O 3 /Au/Ag layered films suppor... more The strain-resistance transduction of commercially available In 2 O 3 /Au/Ag layered films supported by polyethyl-ene terephthalate (PET) foil was studied. A colossal gauge factor as high as about 60,000 was observed upon a strain of 1%. Such ultra-high response is presumably owing to conductivity derived from the tunnelling current across cracks formed in the strained In 2 O 3 film; the cracks – as visualized by scanning electron microscopy – are oriented perpendicularly to the strain vector and are noted for their uniform width across the sample. It is further demonstrated that the standardly defined gauge factor is incommensurate for strain sensors with transduc-tion based on the tunnelling current and a redefined formula for the gauge factor was proposed.
Mater Sci Eng a Struct Mater, 1997
Acta Physica Polonica A, 2009
Sensors and Actuators A: Physical, 2016
DESCRIPTION SAXS, nanoparticle monolayer, strain sensor
Journal of Raman Spectroscopy, 2015
We report on a reference-free Raman spectroscopy method for a precise thickness determination of ... more We report on a reference-free Raman spectroscopy method for a precise thickness determination of the multilayered graphene oxide flakes. The method is based on the normalization of the total integral intensity of D and G Raman bands to the integral intensity of the second-order optical phonon peak of the silicon substrate in the Raman spectrum. The normalization provides discrete ratio values corresponding to the number of graphene oxide layers in the respective flakes with the intensity linearly increasing with the number of layers. This provides a fast and robust determination of the thickness of graphene oxide flakes in terms of the layer number up to high values. A comparison with conventional spectrally resolved reflectivity mapping shows similar sensitivity, while selectivity to particular functional chemical groups is a bonus of the Raman-based method. Copyright
Acta Crystallographica Section A Foundations and Advances, 2014
Self-assembled metal oxide nanoparticle layers have attracted much attention recently due to pote... more Self-assembled metal oxide nanoparticle layers have attracted much attention recently due to potential applications in sensors. Here we report on a UV/ozone-driven re-assembly and oxidation of a self-assembled silver nanoparticle bilayer deposited by a modified Langmuir-Schaefer technique that was probed in-situ by simultaneous measurements of the small- and wide-angle X-ray scattering at grazing incidence (GISAXS, GIWAXS). The experiments were performed at BL23A endstation of NSRRC, Taiwan. Four distinct stages of the system response to the UV/ozone treatment were identified. In the first stage 0-120 s, a gradual extinction of Bragg rods and the nanoparticle short-range order due to a gradual surfactant removal is observed in GISAXS that is connected with an array densification and order improvement obeying the paracrystal model in the shrinking self-assembled regions. In the second stage 120-360 s, the original self-assembly goes to a total extinction while the integral intensity ...