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DFT and TOF-SIMS study of the interaction between hydrogen sulfide ion and malachite (–201) surface

Mao Yingbo, Wu Dandan, Huang Lingyun

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 5

71--79

EN

In this paper, the mechanism of interaction between hydrogen sulfide ions and malachite was investigated using density functional theory (DFT) calculations and time of flight secondary ion mass spectrometry (TOF-SIMS). The DFT calculations showed that HS− adsorption on the malachite (−201) surface was stronger than that of S adsorption resulting from the higher number of electron transfers in the solution which accelerated the sulfidation reaction rate. Density of states (DOS) analysis showed that the near Fermi level was jointly contributed to by the Cu 3d, O 2p, O 2S, and S 3P orbits after adsorption of HS− on the malachite (–201)surface. It was found that the 2p orbital of O and the 3p orbital of S overlapped, indicating that S not only reacted with Cu, but also with O. The TOF-SIMS detected S− and CuS2− fragment ion peaks in the 0−150 m/z negative segment of mass spectra. TOF-SIMS also showed that copper sulfide films of certain thicknesses were formed, demonstrating the effectiveness of hydrogen sulfide sulfidation in flotation processes.

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Zastosowanie spektrometrii mas jonów wtórnych z analizatorem czasu przelotu (TOF-SIMS) do badań odporności korozyjnej warstw konwersyjnych wytworzonych działaniem chromu(III) na powłoki cynkowe na stali węglowej

Rogowski J., Socha M., Socha A.

Przemysł Chemiczny

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2017

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T. 96, nr 11

2317--2323

PL

Metodą spektrometrii mas jonów wtórnych z analizatorem czasu przelotu (TOF-SIMS) zanalizowano skład chemiczny warstw konwersyjnych wytworzonych na próbkach stali węglowej pokrytych warstwą cynku. Odporność badanych warstw na korozję wyznaczono na podstawie krzywych polaryzacyjnych, pomiaru ich impedancji oraz z wykorzystaniem komory solnej. Stwierdzono, że w procesie pasywacji zachodzi reakcja między związkami chromu a cynkiem, prowadząca do zmiany składu chemicznego powierzchni, w tym utworzenia mieszanych tlenków ZnCrxOy. Wykazano korelacje szybkości korozji wyznaczonej metodą elektrochemiczną oraz w komorze solnej z zawartością jonów fluorkowych w warstwie pasywnej oraz rezystancją warstwy porowatej.

EN

Samples of C steel coated with a 8 μm thick layer of Zn were treated with HNO₃ soln. and then passivated in com. Cr(III) salt solns. to produce conversion layers. Corrosion resistance of the layers was detd. on basis of polarization curves, impedance measurements and salt chamber tests. The chem. compn. of the layers was analyzed by using TOF-SIMS. The Cr compds. reacting with Zn during passivation resulted in formation of mixed ZnCrxOy oxides. Furthermore, the corrosion rate detd. by electrochem. methods and saline chamber test depended on the content of F ions in the passive layer.

3

Characterization Of Oxide Layers Produced On The AISI 321 Stainless Steel After Annealing

Bochnowski W., Dziedzic A., Adamiak S., Berchenko M., Trzyna M., Cebulski J.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 3

2327--2334

EN

In this study, the structure, chemical composition and topography of oxide layers produced on the surface of the AISI 321 austenitic steel in the annealing process were analyzed. Heat treatment was done at 980°C temperature for 1 hour time in different conditions. The annealing was done in a ceramic furnace in oxidation atmosphere and in vacuum furnaces with cylindrical molybdenum and graphite chambers. The analysis was carried out using the following methods: a scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectrometer (EDX), a transmission electron microscope (TEM) equipped with an energy-dispersive X-ray spectrometer (EDX), an X-ray diffractometer (XRD), a secondary ion mass spectrometer with time-of-flight mass analyzer (TOF SIMS) and an atomic force microscope (AFM). The oxide layer formed during annealing of the AISI 321 steel at 980°C consisted of sub-layers, diversified in the chemical composition. The thickness of the oxidized layer is depended on the annealing conditions. In a ceramic furnace in oxidation atmosphere, the thickness of the oxide layer was of 300-500 nm, in a vacuum furnace with molybdenum and graphite heating chambers, it ranged from 40 to 300 nm and from a few to 50 nm, respectively. TOF SIMS method allows to get average (for the surface of 100 μm × 100 μm) depth profiles of concentration of particular elements and elements combined with oxygen. In oxide layers formed in vacuum furnaces there are no iron oxides. Titanium, apart from being bounded with carbon in carbides, is a component of the oxide layer formed on the surface of the AISI 321 steel.

PL

W pracy analizowano strukturę, skład chemiczny oraz topografię warstwy tlenków powstałych na powierzchni stali austenitycznej AISI 321 w procesie wyżarzania. Obróbkę cieplną prowadzono w temperaturze 980°C w czasie 1 godziny w zróżnicowanych warunkach. Wyżarzanie prowadzono w piecu ceramicznym w atmosferze powietrza oraz w piecach próżniowych z cylindryczną komorą molibdenową i grafitową. W prowadzonej analizie wykorzystano skaningowy mikroskop elektronowy (SEM) wyposażony w spektrometr promieniowania X (EDX), transmisyjny mikroskop elektronowy (TEM) wyposażony w spektrometr promieniowania X (EDX), dyfraktometr rentgenowski (XRD X-Ray Diffraction), spektrometr mas jonów wtórnych z analizatorem czasu przelotu (TOF SIMS) oraz mikroskop sił atomowych (AFM). Warstwa tlenków powstała w wyniku wyżarzania stali AISI 321 w temperaturze 980°C składała się z podwarstw różniących się składem chemicznym. O grubości warstwy utlenionej w decydowały warunki wyżarzania. W piecu ceramicznym z atmosferą powietrza grubość warstwy tlenków wynosiła 300-500 μm, w piecu próżniowym z grafitową i molibdenową komorą grzejną grubości wynosiły odpowiednio od 40 nm do 300 nm oraz kilka nm do 50 nm. Badania TOF SIMS pozwalają otrzymać uśrednione profile koncentracji pierwiastków metalicznych oraz profile koncentracji pierwiastków metalicznych będących w kontakcie z tlenem. W warstwach tlenków powstałych w piecach próżniowych nie obserwowano tlenków żelaza. Tytan oprócz roli związania węgla w węglikach, wchodzi w skład warstwy tlenków tworzonych w piecu próżniowym na powierzchni stali AISI 321.

4

Nowe podejście do badania śladów w kryminalistyce

Szynkowska M. I., Osingłowska K., Pawlaczyk A., Palińska K., Marcinek M., Rogowski J., Czubak A., Parczewski A.

Przemysł Chemiczny

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2013

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T. 92, nr 6

1125--1133

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Charakterystyka materiału włóknistego z zastosowaniem metod XRF, XPS, SEM oraz ToF-SIMS

Kubacki J., Mańka M., Balin K., Miros A.

Materiały Ceramiczne

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2013

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T. 65, nr 4

424--428

PL

W pracy przedstawiono wyniki badań przemysłowych materiałów termoizolacyjnych z wykorzystaniem technik spektroskopowych i mikroskopowych. Przeprowadzone badania miały na celu scharakteryzowanie struktury i składu chemicznego materiału włóknistego używanego do produkcji wełny mineralnej. Analiza składu chemicznego wykazała obecność azotu, krzemu, glinu, żelaza, sodu, magnezu i wapnia na poziomie kilku procent atomowych, oraz tlenu i węgla na poziomie kilkudziesięciu procent atomowych. Wyniki badań uzyskane metodami XRF oraz XPS wykazały odwrócony stosunek koncentracji atomowej tlenu i węgla. Określona została średnica włókien. Otrzymane z widm masowych mapy chemiczne wykazały homogeniczny rozkład pierwiastków dla pojedynczych włókien. Otrzymane wyniki stanowią bazę do zaplanowania eksperymentów wiążących skład chemiczny surowców, służących do produkcji wełny mineralnej, z właściwościami cieplnymi wyrobów finalnych.

EN

This paper presents the results of industrial investigations of thermal insulation materials by using spectroscopic and microscopic techniques. The goal of this study was to characterize a structure and chemical composition of fibrous material used in production of mineral wool. Analysis of the chemical composition showed the presence of nitrogen, silicon, aluminium, iron, sodium, magnesium and calcium at the level of a few atomic percent, and several atomic percent of carbon and oxygen. The results obtained by XRF and XPS methods showed an inverted value of atomic concentration for oxygen and carbon. The mean diameter of a single fibre was determined. The homogeneous distribution of chemical elements within an individual fibre was determined from a chemical map obtained by SIMS. The obtained results form the basis for planning experiments aimed at finding a relationship between chemical composition of the materials used for production of mineral wool and the thermal properties of final products.

6

Characterization of Cu-(Ag, Au)/CrAl3O6 Methanol Synthesis Catalysts by TOF-SIMS and SEM-EDS Techniques

Maniecki T. P., Mierczyński P., Bawolak K., Leśniewska E., Rogowski J., Jóźwiak W. K.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 9

1643-1651

EN

Characterization of bimetallic Cu-Ag and Cu-Au catalytic systems supported on CrAl3O6 was carried out by TOF-SIMS, XRD and SEM-EDS techniques. The evidence of alloying of copper and second metal was observed during catalyst reduction as well as methanol syntheis reaction. The promoting effect of noble metal catalysts on copper catalyst was noticed. Modification by gold or silver improves activity up to ten times.

7

Influence of Au/Fe2O3 and Au/TiO2 Catalysts Preparation on Their Activity in CO Oxidation by Oxygen and Water Gas Shift Reactions

Jóźwiak W. K., Kaczmarek E., Ignaczak W.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 1-2

213-222

EN

Supported Au/Fe2O3 and Au/TiO2 catalysts appear very active in both carbon monoxide oxidation by oxygen or water. The aim of this work was to find correlation between gold catalysts activity andmethods of their preparation (impregnation and deposition-precipitation), the influence of alkali ions additives and temperature of calcination. The physico-chemical properties of Au/Fe2O3 and Au/TiO2 catalysts were investigated by TPR, ToF-SIMS and catalytic activity methods. Carbon monoxide conversion degree in oxidation by oxygen is higher for Au/Fe2O3 than for Au/TiO2 catalyst, but the activity of gold catalysts in carbon monoxide oxidation by water is opposite. The most active catalyst was Au/Fe2O3 prepared by deposition-precipitation method with an addition of urea and those catalysts prepared by impregnation method with an addition of KOH. The analogically prepared Au/TiO2 catalyst exhibited comparable activity. The gold catalysts appear the most active after drying at 60 graduate C – the role of disordered catalyst structure and hydroxyl groups. The carbon monoxide conversion degree depends on the applied precipitate agent in the following order: KOH > Na2CO3 > NH3. The gold catalysts do not lose catalytic activity during long lasting tests (170 h) and do not suffer on the presence of moisture and chlorine in catalyst system. The impregnated Au(K)/Fe2O3 catalysts with a ratio Cl/Au = 4/1 – 8/1 show considerable activity.

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ToF-SIMS studies of the surface of Pd/ZrO2-TiO2 catalyst used in the hydrodechlorination process

Grams J., Góralski J., KLeczewska J., Szczepaniak B., Paryjczak T.

Polish Journal of Chemical Technology

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2007

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Vol. 9, nr 3

81-85

EN

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used in order to obtain the information about the surface composition of Pd/ZrO2-TiO2 catalyst and to estimate the changes in the concentration of particular components on its surface during the hydrodechlorination of CCl4. The results demonstrated that the hydrodechlorination process led to the increase in the concentration of chlorine and the drop in the amount of surface accessible palladium, while the quantity of Pd-Cl bounds did not change considerably. It suggested that the presence of ZrO2 protected the surface of the studied catalyst against the formation of PdCI2.

9

Surface characterization of different particles arising as a result of coal combustion process in selected power plants from Central Poland using ToF-SIMS

Grams J., Bawolak K.

Polish Journal of Chemical Technology

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2007

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Vol. 9, nr 4

77-80

EN

The aim of this work was the ToF-SIMS investigations of different particles arising as a result of a coal combustion process in selected power plants from Central Poland. The chemical composition and distribution of particular compounds on the studied surfaces were determined. Moreover, the ratio of the quantity of aromatic and aliphatic hydrocarbons adsorbed on the surface of the particles was estimated. A qualitative analysis of the studied samples demonstrated the presence of a big number of various compounds, including heavy metals such as Pb, Cd and As on the investigated surfaces. In the prevailing number sample components were distributed non-homogenously on the surface and the larger areas richer in a certain type of ions were observed.

10

Application of the TOF-SIMS and SEM-EDS methods to assess the influence of dusting from a phosphate waste deposal place based on hair analysis

Szynkowska M.I., Leśniewska E., Pawlaczyk A., Rogowski J., Paryjczak T.

Polish Journal of Chemical Technology

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2007

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Vol. 9, nr 4

85-90

EN

In this work, scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS) and the time-of-flight secondary ion mass spectrometry (TOF-SIMS) were used to study the particles present on the hair surface of the inhabitants of Wislinka (people environmentally exposed due to the closeness of a dump) in order to obtain the information about the possible influence of dusting from a phosphate waste deposal place. Additionally, the morphology and the composition of fresh phosphogypsum were analyzed. Waste phosphogypsum is formed in the process of a wet phosphoric acid production and there is still a problem with its storage. A thorough understanding of the composition and chemistry of phosphogypsum seems to be necessary to evaluate its environmental impact comprehensively. The results obtained from these two techniques turned out to be complementary and revealed the information expected.

11

Surface characterization of palladium catalysts using time-of-flight secondary ion mass spectrometry (ToF-SIMS)

Grams J., Góralski J., Szczepaniak B., Paryjczak T.

Polish Journal of Chemical Technology

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2006

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Vol. 8, nr 2

106-108

EN

This paper presents potentialities of time-of-flight secondary ion mass spectrometry in surface characterization of palladium catalysts destined for hydrodechlorination reaction. The secondary ion mass spectra collected from the surface of the analyzed catalysts allowed to obtain useful information regarding surface composition, presence of contaminants and interactions between particular surface components. Moreover, the amount of Cl containing species formed on the catalyst surface during hydrodechlorination reaction was also estimated.

12

Analiza składu chemicznego obszaru przejściowego w układzie DLC/Si

Staryga E., Rogowski J., Knapik M., Jarzyńska D., Cłapa M.

Elektronika : konstrukcje, technologie, zastosowania

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2006

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Vol. 47, nr 11

12-14

PL

Warstwy diamentopodobnego węgla są atrakcyjnym materiałem ze względu na dużą twardość, odporność chemiczną oraz właściwości elektryczne. Właściwości fizykochemiczne warstw DLC są ściśle związane z warunkami i parametrami procesu osadzania, dlatego też istotne jest zbadanie składu chemicznego warstw oraz ich struktury w zależności od parametrów wytwarzania. Badania składu chemicznego warstw wykonano przy użyciu spektrometrii mas jonów wtórnych TOF-SIMS. Warstwy DLC osadzono na gładkich podłożach krzemowych przy użyciu techniki RF PCVD (13,56 MHz). Warstwy nakładane były przy różnych wartościach ujemnego potencjału autopolaryzacji z zakresu od -60 V do -420 V. Zarejestrowano widma masowe i profile głębokościowe dla powierzchni, objętości i obszaru granicznego układu DLC/Si. W składzie chemicznym warstwy DLC, oprócz węgla, zarejestrowano wodór i tlen. Uzyskane profile głębokościowe wskazują na obecność zanieczyszczeń takich jak żelazo i chrom w obszarze granicznym pomiędzy podłożem a warstwą DLC.

EN

Diamond-like carbon (DLC) films attract considerable interest due to their mechanical hardness, chemical inertness, optical transparency and electrical properties. Those properties are highly influenced by the deposition parameters and in turn should be correlated with chemical composition and structure of the DLC films. In this study the Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) was used to analyze chemical composition of DLC films deposited at various preparation parameters. The DLC films were deposited on flat Si substrates using Radio Frequency Plasma Chemical Vapour Deposition (RF PCVD 13.56 MHz) method. Deposition of samples was carried out using various negative self-bias voltage of electrode between -60 V and -420 V. Both surface and bulk chemical composition was analyzed for all samples by recorded surface mass spectra and depth profiles respectively.