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Catalytic Thermal Decomposition of NO₂ by Iron(III) Nitrate Nonahydrate-Doped Poly(Vinylidene Difluoride).

ABSTRACT: The products of thermal decomposition of iron nitrate nonahydrate doped into poly(vinylidene difluoride) are examined using Mössbauer spectroscopy. Very little of the expected nitrogen dioxide product is observed, which is attributed to Fe³⁺ catalysis of the decomposition of NO₂. The active site of the catalysis is shown to be Fe(OH)₃ in the polymer matrix, which is, unexpectedly, reduced to Fe(OH)₂. Thermodynamic calculations show that the reduction of Fe³⁺ is exergonic at sufficiently high temperatures. A reaction sequence, including a catalytic cycle for decomposition of NO₂, is proposed that accounts for the observed reaction products. The role of the polymer matrix is proposed to inhibit transport of gas-phase products, which allows them to interact with Fe(OH)₃ doped in the polymer.

SUBMITTER: Sumathirathne L

PROVIDER: S-EPMC9730309 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Catalytic Thermal Decomposition of NO2 by Iron(III) Nitrate Nonahydrate-Doped Poly(Vinylidene Difluoride).

Sumathirathne Lasanthi L Hasselbrink Carson Lawrence CL Hayes Dugan D Euler William B WB

ACS omega 20221117 48

The products of thermal decomposition of iron nitrate nonahydrate doped into poly(vinylidene difluoride) are examined using Mössbauer spectroscopy. Very little of the expected nitrogen dioxide product is observed, which is attributed to Fe3+ catalysis of the decomposition of NO2. The active site of the catalysis is shown to be Fe(OH)3 in the polymer matrix, which is, unexpectedly, reduced to Fe(OH)2. Thermodynamic calculations show that the reduction o ...[more]

PMID: 36506204

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