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Papers by Ryszard Kaleńczuk

Open Chemistry, Jun 1, 2013

The Co 3 O 4 /LiNbO 3 composites were synthesized by impregnation of LiNbO 3 in an aqueous soluti... more The Co 3 O 4 /LiNbO 3 composites were synthesized by impregnation of LiNbO 3 in an aqueous solution of cobalt nitrate and next by calcination at 400°C. The activity of produced samples has been investigated in the reaction of photocatalytic hydrogen generation. The crystallographic phases, optical and vibronic properties were studied using X-ray diffraction (XRD), diffuse reflectance (DR) UV-vis and resonance Raman spectroscopic techniques, respectively. The influence of cobalt content (range from 0.5 wt.% to 4 wt.%) on the photocatalytic activity of Co 3 O 4 /LiNbO 3 composites for photocatalytic hydrogen generation has been investigated. Co 3 O 4 /LiNbO 3 composites exhibited higher than LiNbO 3 photocatalytic activity for hydrogen generation. The highest H 2 evolution efficiency was observed for Co 3 O 4 /LiNbO 3 composite with 3 wt.% cobalt content. The amount of H 2 obtained in the presence of LiNbO 3 and Co 3 O 4 /LiNbO 3 (3 wt.% of cobalt content) was 1.38 µmol/min and 2.59 µmol min-1 , respectively.

Journal of Physics and Chemistry of Solids, Feb 1, 2011

Fe-, Ni-, Co- and Ag- loaded NaNbO3 catalysts were prepared and their activities have been invest... more Fe-, Ni-, Co- and Ag- loaded NaNbO3 catalysts were prepared and their activities have been investigated in the reaction of photocatalytic hydrogen generation. Me/NaNbO3 were synthesized by impregnation of NaNbO3 in an aqueous solution of metal nitrates and then by calcination at the temperature of 400°C. The crystallographic phases and optical and vibronic properties were examined by X-ray diffraction (XRD) and diffuse reflectance (DR) UV–vis and resonance Raman spectroscopic methods, respectively. Morphology and chemical composition of the produced samples were studied using a high-resolution transmission electron microscope (HR-TEM) and an energy dispersive X-Ray spectrometer (EDX) as its mode. The detailed analysis has revealed that all the investigated catalysts exhibit high crystallinity and the presence of Fe2O3, NiO, Co3O4 and Ag2O oxides on Me/NaNbO3 was confirmed. Finally, the influence of different metal loadings (Fe, Ni, Co and Ag) on the photocatalytic activity of NaNbO3 for photocatalytic hydrogen generation has been investigated. Here we report that among all the Me/NaNbO3 photocatalysts Ag-loaded NaNbO3 exhibited higher photocatalytic efficiency for photocatalytic hydrogen generation than NaNbO3.

Polish Journal of Chemical Technology, 2003

Polish Journal of Chemical Technology, 2001

Polish Journal of Chemical Technology, 2004

Polish Journal of Chemical Technology, 2005

Polish Journal of Chemical Technology, 2001

Chemischer Informationsdienst, 1981

EPR‐Messungen an ,rwasserfreiem FeCl3, natürlichem Graphit, lamellaren Graphit‐ FeCl3 ‐Verbindung... more EPR‐Messungen an ,rwasserfreiem FeCl3, natürlichem Graphit, lamellaren Graphit‐ FeCl3 ‐Verbindungen und lamellaren Graphit‐FeC13 ‐Kalium‐Verbindungen mitverschiedenen K/Fe‐Verhältnissen bestätigen den Elektronendonatorcharakter des Graphits in den GraphiteFeC13 ‐Verbindungen.

Materials Science Forum, 2015

In the present study, an attempt was made to synthesize ZnO/TiO2 and ZnO/TiO2/CuO nanocomposites ... more In the present study, an attempt was made to synthesize ZnO/TiO2 and ZnO/TiO2/CuO nanocomposites as photocatalyst for degradation of organic pollutant (methylene blue) in aqueous solution under UV and visible light irradiation. Characterization using X-ray diffraction, energy dispersive X-ray spectroscopy, field emission scanning microscope electron, diffuse reflectance spectroscopy analysis confirmed that all three components phase are present in the photocatalyst. The photodegradation of organic pollutant showed that with the incorporation of CuO content in ZnO/TiO2 nanocomposites increasing the photocatalytic performance in ultraviolet as well as visible region.

Chemie Ingenieur Technik, 1980

Unter Wellenfrontanalyse [l] wird hier die Analyse der Relaxationsvorgange um die Front einer Kon... more Unter Wellenfrontanalyse [l] wird hier die Analyse der Relaxationsvorgange um die Front einer Konzentrationsstorung verstanden. Dabei unterscheidet man zwischen der sog. Ortsrelaxation, d. i. die Amplitudenanderung der Wellenfront langs der Ausbreitungskoordinate, und der Zeitrelaxation, d. i. die restliche ubergangsfunktion. Ortsrelaxation, Ausbreitungsgeschwindigkeit der Wellenfront und Zeitgradient zu Beginn der Zeitrelaxation hangen allein (und in einfacher Weise) vom stationaren Ausgangszustand des Systems ab, in welchem sich die Konzentrationsstorung ausbreitet. Bei der Untersuchung, uber die hier berichtet wird, 1st nur die Ortsrelaxation ausgewertet worden. Sie sol1 durch eine spatere Arbeit erganzt werden, bei der auch die Zeitrelaxation als weiteres Element der Wellenfrontanalyse verwendet wird. Die Ortsrelaxation liefert Informationen uber die Mikrokinetik, d. h. uber die Art der Teilmechanismen, nach denen die untersuchte Reaktion ablauft, und uber die Zahlenwerte der einschlagigen kinetischen Parameter. Neben der mikrokinetischen Relaxation (von

Open Chemistry, Jun 1, 2013

The Co 3 O 4 /LiNbO 3 composites were synthesized by impregnation of LiNbO 3 in an aqueous soluti... more The Co 3 O 4 /LiNbO 3 composites were synthesized by impregnation of LiNbO 3 in an aqueous solution of cobalt nitrate and next by calcination at 400°C. The activity of produced samples has been investigated in the reaction of photocatalytic hydrogen generation. The crystallographic phases, optical and vibronic properties were studied using X-ray diffraction (XRD), diffuse reflectance (DR) UV-vis and resonance Raman spectroscopic techniques, respectively. The influence of cobalt content (range from 0.5 wt.% to 4 wt.%) on the photocatalytic activity of Co 3 O 4 /LiNbO 3 composites for photocatalytic hydrogen generation has been investigated. Co 3 O 4 /LiNbO 3 composites exhibited higher than LiNbO 3 photocatalytic activity for hydrogen generation. The highest H 2 evolution efficiency was observed for Co 3 O 4 /LiNbO 3 composite with 3 wt.% cobalt content. The amount of H 2 obtained in the presence of LiNbO 3 and Co 3 O 4 /LiNbO 3 (3 wt.% of cobalt content) was 1.38 µmol/min and 2.59 µmol min-1 , respectively.

Journal of Physics and Chemistry of Solids, Feb 1, 2011

Fe-, Ni-, Co- and Ag- loaded NaNbO3 catalysts were prepared and their activities have been invest... more Fe-, Ni-, Co- and Ag- loaded NaNbO3 catalysts were prepared and their activities have been investigated in the reaction of photocatalytic hydrogen generation. Me/NaNbO3 were synthesized by impregnation of NaNbO3 in an aqueous solution of metal nitrates and then by calcination at the temperature of 400°C. The crystallographic phases and optical and vibronic properties were examined by X-ray diffraction (XRD) and diffuse reflectance (DR) UV–vis and resonance Raman spectroscopic methods, respectively. Morphology and chemical composition of the produced samples were studied using a high-resolution transmission electron microscope (HR-TEM) and an energy dispersive X-Ray spectrometer (EDX) as its mode. The detailed analysis has revealed that all the investigated catalysts exhibit high crystallinity and the presence of Fe2O3, NiO, Co3O4 and Ag2O oxides on Me/NaNbO3 was confirmed. Finally, the influence of different metal loadings (Fe, Ni, Co and Ag) on the photocatalytic activity of NaNbO3 for photocatalytic hydrogen generation has been investigated. Here we report that among all the Me/NaNbO3 photocatalysts Ag-loaded NaNbO3 exhibited higher photocatalytic efficiency for photocatalytic hydrogen generation than NaNbO3.

Polish Journal of Chemical Technology, 2003

Polish Journal of Chemical Technology, 2001

Polish Journal of Chemical Technology, 2004

Polish Journal of Chemical Technology, 2005

Polish Journal of Chemical Technology, 2001

Chemischer Informationsdienst, 1981

EPR‐Messungen an ,rwasserfreiem FeCl3, natürlichem Graphit, lamellaren Graphit‐ FeCl3 ‐Verbindung... more EPR‐Messungen an ,rwasserfreiem FeCl3, natürlichem Graphit, lamellaren Graphit‐ FeCl3 ‐Verbindungen und lamellaren Graphit‐FeC13 ‐Kalium‐Verbindungen mitverschiedenen K/Fe‐Verhältnissen bestätigen den Elektronendonatorcharakter des Graphits in den GraphiteFeC13 ‐Verbindungen.

Materials Science Forum, 2015

In the present study, an attempt was made to synthesize ZnO/TiO2 and ZnO/TiO2/CuO nanocomposites ... more In the present study, an attempt was made to synthesize ZnO/TiO2 and ZnO/TiO2/CuO nanocomposites as photocatalyst for degradation of organic pollutant (methylene blue) in aqueous solution under UV and visible light irradiation. Characterization using X-ray diffraction, energy dispersive X-ray spectroscopy, field emission scanning microscope electron, diffuse reflectance spectroscopy analysis confirmed that all three components phase are present in the photocatalyst. The photodegradation of organic pollutant showed that with the incorporation of CuO content in ZnO/TiO2 nanocomposites increasing the photocatalytic performance in ultraviolet as well as visible region.

Chemie Ingenieur Technik, 1980

Unter Wellenfrontanalyse [l] wird hier die Analyse der Relaxationsvorgange um die Front einer Kon... more Unter Wellenfrontanalyse [l] wird hier die Analyse der Relaxationsvorgange um die Front einer Konzentrationsstorung verstanden. Dabei unterscheidet man zwischen der sog. Ortsrelaxation, d. i. die Amplitudenanderung der Wellenfront langs der Ausbreitungskoordinate, und der Zeitrelaxation, d. i. die restliche ubergangsfunktion. Ortsrelaxation, Ausbreitungsgeschwindigkeit der Wellenfront und Zeitgradient zu Beginn der Zeitrelaxation hangen allein (und in einfacher Weise) vom stationaren Ausgangszustand des Systems ab, in welchem sich die Konzentrationsstorung ausbreitet. Bei der Untersuchung, uber die hier berichtet wird, 1st nur die Ortsrelaxation ausgewertet worden. Sie sol1 durch eine spatere Arbeit erganzt werden, bei der auch die Zeitrelaxation als weiteres Element der Wellenfrontanalyse verwendet wird. Die Ortsrelaxation liefert Informationen uber die Mikrokinetik, d. h. uber die Art der Teilmechanismen, nach denen die untersuchte Reaktion ablauft, und uber die Zahlenwerte der einschlagigen kinetischen Parameter. Neben der mikrokinetischen Relaxation (von