From Prussian blue to iron carbides: high-temperature XRD monitoring of thermal transformation under inert gases

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F17%3A73583084" target="_blank" >RIV/61989592:15310/17:73583084 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.cambridge.org/core/journals/powder-diffraction/article/from-prussian-blue-to-iron-carbides-hightemperature-xrd-monitoring-of-thermal-transformation-under-inert-gases/F1AC86BCD9AD1467FE6B071564137C37" target="_blank" >https://www.cambridge.org/core/journals/powder-diffraction/article/from-prussian-blue-to-iron-carbides-hightemperature-xrd-monitoring-of-thermal-transformation-under-inert-gases/F1AC86BCD9AD1467FE6B071564137C37</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1017/S0885715617000471" target="_blank" >10.1017/S0885715617000471</a>

Jazyk výsledku

angličtina

Název v původním jazyce

From Prussian blue to iron carbides: high-temperature XRD monitoring of thermal transformation under inert gases

Popis výsledku v původním jazyce

The thermal behavior and decomposition reaction of Prussian blue (PB) (Fe-4(3+)[Fe2+(CN)(6)](3)center dot xH(2)O) was studied under inert atmosphere of argon by simultaneous thermogravimetry and differential scanning calorimetry, from room temperature up to 900 degrees C, with a heating rate of 5 K min(-1). Parallel to the thermogravimetric measurements, the thermal process was monitored by in situ X-ray powder diffraction (XRD) technique under nitrogen atmosphere. The thermogravimetric data show six steps, corresponding to different stages of the decomposition reaction; comparable results are also obtained by in situ XRD. In addition, a set of PB samples heated up to selected temperatures (190, 300, 370, 540, 680, and 790 degrees C) were ex situ analyzed by powder XRD and Mossbauer spectroscopy. It is found that PB exhibits a negative thermal expansion prior to the water release from its crystalline lattice. Above 300 degrees C, the decomposition is based on the release of cyanogen gas from the PB structure. At 370 degrees C, a cubic iron cyanide compound is formed, while at higher temperatures several iron carbides were found. The subsequent thermal treatment of these carbides leads to the formation of metallic iron and graphite.

Název v anglickém jazyce

From Prussian blue to iron carbides: high-temperature XRD monitoring of thermal transformation under inert gases

Popis výsledku anglicky

The thermal behavior and decomposition reaction of Prussian blue (PB) (Fe-4(3+)[Fe2+(CN)(6)](3)center dot xH(2)O) was studied under inert atmosphere of argon by simultaneous thermogravimetry and differential scanning calorimetry, from room temperature up to 900 degrees C, with a heating rate of 5 K min(-1). Parallel to the thermogravimetric measurements, the thermal process was monitored by in situ X-ray powder diffraction (XRD) technique under nitrogen atmosphere. The thermogravimetric data show six steps, corresponding to different stages of the decomposition reaction; comparable results are also obtained by in situ XRD. In addition, a set of PB samples heated up to selected temperatures (190, 300, 370, 540, 680, and 790 degrees C) were ex situ analyzed by powder XRD and Mossbauer spectroscopy. It is found that PB exhibits a negative thermal expansion prior to the water release from its crystalline lattice. Above 300 degrees C, the decomposition is based on the release of cyanogen gas from the PB structure. At 370 degrees C, a cubic iron cyanide compound is formed, while at higher temperatures several iron carbides were found. The subsequent thermal treatment of these carbides leads to the formation of metallic iron and graphite.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/LO1305" target="_blank" >LO1305: Rozvoj centra pokročilých technologií a materiálů</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Powder Diffraction

ISSN

0885-7156

e-ISSN

—

Svazek periodika

32

Číslo periodika v rámci svazku

SEP 2017

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

6

Strana od-do

"S207"-"S212"

Kód UT WoS článku

000410195100033

EID výsledku v databázi Scopus

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