Przeglądanie według Autor "Sawicka-Chudy, Paulina"

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Characteristics of TiO2, Cu2O, and TiO2/Cu2O thin films for application in PV devices
(AIP Advance, 2019) Sawicka-Chudy, Paulina; Sibiński, Maciej; Pawełek, Ryszard; Wisz, Grzegorz; Cieniek, Bogumił; Potera, Piotr; Szczepan, Patryk; Adamiak, Stanisław; Cholewa, Marian; Głowa, Łukasz
Several Cu2O and TiO2 thin films and four additional TiO2/Cu2O structures were fabricated by direct current (DC) magnetron sputtering. The process parameters were selected on the basis of earlier studies and numerical simulations. We examined the morphology of a cross-section of the PV structures, roughness and topography, and the transmission spectra of the thin films. Additionally, the properties of the samples were determined by X-ray diffraction. Next, the morphology cross-sectional and layer compositions of the solar cells was evaluated by scanning electron microscopy. Only one of the TiO2/Cu2O structures appeared smooth and homogeneous with columnar-type growth. For the as-grown films, diffraction peaks were observed and identified as brookite, rutile, CuO, and Cu2O and the average roughness of the samples was 0.5, 1.2, 5.4, and 4.0 nm, respectively. Finally, the transmission spectra of the thin films were recorded. Transmission and reflection spectra of ultraviolet-visible spectroscopy were analyzed, and the optical band gap and absorption coefficient of the oxidized layers were calculated. In the region of 400 to 1000 nm, transmittance varied from 5% to 70% in the TiO2 samples, and from 15% to 40% in the Cu2O samples, and reflectance of the TiO2 and Cu2O samples ranged from 20% to 90%. In the region of 1.5 eV to 3.5 eV, the mean absorption coefficient varied from ∼105 1/cm to ∼3 · 105 1/cm for TiO2 thin film, and from ∼2 · 105 to ∼6 · 105 1/cm for Cu2O thin film. The optical band gap values of the samples shifted slightly toward bulk anatase-3.5 eV, bulk rutile-3.1 eV, and copper(I) oxide. Finally, silver contacts were used for the electrodes. One of the fabricated TiO2/Cu2O PV structures was found to be sensitive to electromagnetic radiance during the experiment.
Cienkowarstwowe ogniwa słoneczne na bazie struktur tlenku tytanu i tlenku miedzi
(Uniwersytet Rzeszowski, 2020-10-07) Sawicka-Chudy, Paulina
Niniejsza rozprawa doktorska przedstawia badania nad konstrukcją nowych typów cienkowarstwowych ogniw fotowoltaicznych na bazie tlenku tytanu i tlenku miedzi. Spójny tematycznie cykl publikacji prezentuje obliczenia uzyskane z wykorzystaniem narzędzi symulacyjnych oraz wyniki eksperymentów prowadzących do wytworzenia tego typu przyrządów. Pierwszym etapem pracy był przegląd i analiza literatury, które pozwoliły na określenie obecnego stanu wiedzy i globalnych osiągnięć. W kolejnym kroku, zaproponowano modele teoretyczne oraz przeprowadzono symulacje komputerowe ogniw TiO2/CuO oraz TiO2/Cu2O przy pomocy programu informatycznego. Sprawność uzyskana w programie dla struktury idealnej wyniosła 22,4% dla TiO2/CuO oraz 13,7% dla TiO2/Cu2O. Następnie w oparciu o przeprowadzone symulacje oraz doniesienia literaturowe, określono parametry technologiczne procesu, które pozwoliły na wytworzenie testowych ogniw, z wykorzystaniem metody reaktywnego stałoprądowego rozpylania magnetronowego, przy pomocy aparatury PVD firmy PREVAC. Jednak pierwsze prototypy nie wykazywały efektu fotowoltaicznego ze względu na niewłaściwe parametry materiałowe warstw. Dlatego kolejnym etapem pracy były szczegółowe badania pojedynczych próbek tlenku tytanu, tlenku miedzi oraz struktur fotowoltaicznych na bazie tych związków. Badania pozwoliły na wyznaczenie parametrów procesowych aparatury, przy których możliwe było otrzymanie funkcjonalnych przyrządów PV. Ogniwo TiO2/CuO wykazało efekt fotowoltaiczny uzyskując maksymalną sprawność konwersji energii na poziomie η = 0,24%.
Comparison of Solar Tracking System Solar Tracking System and Fixed Photovoltaic Modules in Lodz
(Journal of Solar Energy Engineering, 2018-01) Sawicka-Chudy, Paulina; Sibiński, Maciej; Cholewa, Marian; Pawełek, Ryszard
The world energy consumption has exhibited high growth over the last several decades. Alternative energy sources like photovoltaic (PV) systems generate electricity, reduce pollution air, and have little environmental impact. The commonly used fixed-tilt solar panels, however, have low efficiency and high production cost. Thus, it takes a long time to obtain a return on the investment. Solar trackers increase the efficiency of PV systems and are therefore more attractive from a financial point of view. In order to design tracking systems that will be efficient, it is necessary to analyze the results during various periods during the year and over their lifespan. Thus, we performed a comparative study between fixed-tilt panels and the tracking system installed in Lodz, Poland. Fixed-tilt panels are at normal to the Earth's surface (90 deg from horizontal plane) and are attached to a building façade, azimuth 180 deg (S direction) with 15 cm ventilation gap so slight efficiency drop may be presumed. We performed short- and long-term analyses of the solar tracking and fixed-tilt systems, which allowed us to conclude that the panels tracking the sun had an additional gain of energy during the year as compared to the fixed-tilt panels. During some months, however, the solar tracking system did not produce as much energy as the fixed-tilt, vertically positioned panels. These results might be useful in designing and constructing solar tracking PV systems.
Review of the development of copper oxides with titanium dioxide thin-film solar cells
(2020) Sawicka-Chudy, Paulina; Sibiński, Maciej; Rybak-Wilusz, Elżbieta; Cholewa, Marian; Wisz, Grzegorz; Yavorskyi, Rostyslav
Copper oxide-titanium dioxide (TiO2) p–n junctions are promising materials for photovoltaic devices and may reduce production costs due to their low cost and inexpensive production methods compared with silicon solar cells. The present review compares solar cells made with copper oxides combined with TiO2–TiO2/Cu2O and TiO2/CuO heterojunctions, and “cascade heterojunction systems.” First, we describe the main properties of titanium (iv) dioxide (TiO2), cuprous oxide (Cu2O), and cupric oxide (CuO), and their potential applications. Next, we explain the concept of copper oxide and TiO2 heterojunctions. We summarize and present the photovoltaic characteristics (efficiency, fill factor, circuit current density, and open circuit voltage), thickness, preparation method, and electrode type for solar cells comprising copper oxide and TiO2. The efficiency of the solar cells ranged from 0.0005% to 1.62%. The thickness of the TiO2 and cupric oxide layers ranged from 0.06 to 16 µm, and from 0.18 to 1.5 µm, respectively, depending on the fabrication method. Additionally, we review and discuss the available combinations of copper oxide with other materials (Cu2O with ZnO, CuO with ZnO, and CuO with Si), as well as the effect of the thickness of the copper (i) oxide and copper (ii) oxide on the solar cell performance. Finally, we present aspects to improve the conversion efficiency of heterojunction solar cells with copper oxides combined with TiO2. This review will be useful for the construction and further development of thin-film solar cells.