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Grafted iron(iii) ions significantly enhance NO₂ oxidation rate and selectivity of TiO₂ for photocatalytic NO _x abatement.

ABSTRACT: Semiconductor photocatalysis could be an effective means to combat nitrogen oxides (NO _x ) based air pollution through mineralisation of NO _x to nitrate. However, most of the typically TiO₂-based catalysts employed show a much higher reactivity towards NO than NO₂, leading to an accumulation of this unwanted and toxic intermediate. By grafting the photocatalyst with small amounts (≤0.1 at%) of isolated iron(iii) ions, the reactivity towards NO₂ is increased by the factor of 9, bringing it up to par with the NO-reactivity and alleviating the problem with intermediate accumulation. Consequently, the observed selectivity of the reaction is dramatically increased from less than 40% to more than 90%. The paper also discusses possible mechanisms for this very beneficial behavior.

SUBMITTER: Patzsch J

PROVIDER: S-EPMC9084282 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Grafted iron(iii) ions significantly enhance NO2 oxidation rate and selectivity of TiO2 for photocatalytic NO x abatement.

Patzsch Julia J Spencer Jacob N JN Folli Andrea A Bloh Jonathan Z JZ

RSC advances 20180803 49

Semiconductor photocatalysis could be an effective means to combat nitrogen oxides (NO x ) based air pollution through mineralisation of NO x to nitrate. However, most of the typically TiO2-based catalysts employed show a much higher reactivity towards NO than NO2, leading to an accumulation of this unwanted and toxic intermediate. By grafting the photocatalyst with small amounts (≤0.1 at%) of isolated iron(iii) ions, the reactivity towar ...[more]

PMID: 35542738

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