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1

Study on synthesis and photoelectric properties of AgInS2 quantum dots

Yuan Binxia, Luo Zige, Sun Yongjun, Cao Sheng, Cao Lan, Li Min

Polish Journal of Chemical Technology

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2022

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Vol. 24, nr 2

21--26

EN

AgInS2 Quantum dots (AIS QDs) have high quantum yield and catalytic performance, which is promising materials in photo-catalytic and optoelectronic fields. In the paper, it adopted a simple and non-toxic method to synthesize AIS QDs. The effect of reaction temperature on the growth mechanism, optical and physical properties of AIS had been extensively investigated by using L-cysteine as the sulfur source, and their application in catalytic hydrogen production was also studied. The results demonstrated that the fluorescence properties will be quenched with the increase of temperature, indicating that the separation speed of electron hole pairs of samples obtained at higher temperature was faster. Meantime, the electron transport capacity and the photocurrent had also improved with the increase of reaction temperature. Finally, the sample obtained at 100 oC had higher hydrogen production rate.

2

Badania elipsometryczne cienkich warstw ZnO:Al stosowanych jako elektrody w fotowoltaice kosmicznej

Dyndał Katarzyna

Materiały Ceramiczne

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2022

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T. 74, nr 1

13--17

PL

Elipsometria spektroskopowa jest techniką optyczną słu-żącą do badania cienkich warstw. Metoda ta ma nienisz-czący charakter i wysoką dokładność, co sprawia, że jest podstawowym narzędziem badań w różnych dziedzinach w tym w fotowoltaice. W pracy elipsometria spektrosko-powa została wykorzystana do badania cienkich warstw tlenku cynku z domieszką glinu (ZnO:Al), otrzymanych z zastosowaniem techniki osadzania warstw atomowych (ALD). Badania cienkich warstw ZnO:Al były motywowane ich zastosowaniem jako elektrody w fotowoltaice kosmicz-nej. Wyznaczono grubości (d) cienkich warstw oraz ich właściwości optyczne takie jak współczynnik załamania (n) i współczynnika ekstynkcji (k). Strukturę cienkich warstw ZnO:Al określono metodą dyfrakcji promieniowania rent-genowskiego (XRD). Grubość warstw została potwierdzona poprzez jej pomiar za pomocą profilometru. Wyniki badań potwierdziły potencjalne zastosowanie cienkich warstw ZnO:Al jako elektrody w ogniwach PV.

XX

Spectroscopic ellipsometry is an optical technique for studying thin films. The method has a non-destructive nature and high accuracy which makes it a basic tool for research in various fields including photovoltaics. In this paper, spectroscopic ellipsometry was used to measure aluminium-doped zinc oxide (ZnO:Al) thin films obtained using the atomic layer deposition (ALD) technique. The study of ZnO:Al thin films was motivated by their use as electrodes in space photovoltaics. The thicknesses (d) of the thin films and their optical properties such as refrac-tive index (n) and extinction coefficient (k) were deter-mined. The structure of the ZnO:Al thin films was assessed by X-ray diffraction (XRD). The thickness of the thin films was confirmed by measuring it with a profilometer. The results confirmed the potential use of ZnO:Al thin films as electrodes in PV cells.

3

Impact of wild forest fires in Eastern Europe on aerosol composition and particle optical properties

Zieliński T., Petelski T., Strzałkowska A., Pakszys P., Makuch P.

Oceanologia

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2016

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No. 58 (1)

13--24

EN

In this paper the authors discuss the changes of aerosol optical depth (AOD) in the region of eastern Europe and the Baltic Sea due to wild fire episodes which occurred in the area of Belarus and Ukraine in 2002. The authors discuss how the biomass burning aerosols were advected over the Baltic area and changed the composition of aerosol ensemble for a period of several summer weeks. The air pressure situation and slow wind speeds also facilitated the development of such conditions. As a consequence very high AOD levels were recorded, by an order of 3–4 higher versus normal conditions and they significantly increased the annual averages. On particular days of August 2002 the AOD values reached a level of over 0.7. On these days fine particles fully dominated the entire ensemble of aerosol particles. They were either sulfates or smoke particles. Such situation was unique over a period of many years and it had its serious consequences for the region and especially for the Baltic Sea.

4

Annealing Effects on the Interband Transition and Optical Constants of Cobalt Doped Cadmium Oxide Thin Films

Habubi N. F.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 43

81--90

EN

The CdO: Co films have been deposited on substrate temperature at 400 °C by spray pyrolysis method using cadmium chloride and cobalt chloride as a precursors for Cd and Co ions, respectively. The effect of annealing temperature on optical constants of Co: CdO thin films are investigated using UV-Visible spectrophotometer in the range of (300-900) nm at room temperature. The absorbance and optical parameters such as α, n, ε1, ε2, and χ are increased when the annealing temperature increases, while the energy gap decreased from 2.5 eV before annealing to 2.48 eV after 500 °C annealing temperature. Urbach energy is increased with the increasing of annealing temperature from 353 meV for sample before annealing to 715 meV for the same samples annealed at 500 °C.

5

Structural and Optical Characterization of ZnO Nanoparticles Synthesized by Microemulsion Route

Kumar H., Rani R.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 14

26--36

EN

ZnO nanoparticles were synthesized by microemulsion route in W/S ratio of 5 at room temperature. X-ray diffraction (XRD) pattern reveals wurtzite structure of ZnO nanoparticles. Rod shape of ZnO nanoparticles of average particle size 10.0 to 12.0 nm were observed by transmission electron microscopy. FT-IR spectra confirmed the adsorption of surfactant molecules at the surface of ZnO nanoparticles and presence of Zn-O bonding. Thermal studies were carried out by the differential scanning calorimeter (DSC) techniques. In addition, UV-Visible spectra were employed to estimate the band gap energy of ZnO nanoparticles.