Wet hydrogen peroxide catalytic oxidation (WHPCO) is one of the most important industrially applicable advanced oxidation processes (AOPs) for the decomposition of organic pollutants in water. It is demonstrated that manganese functionalized silicate nanoparticles with interparticle porosity act as a superior Fenton‐type nanocatalyst in WHPCO as they can decompose 80% of a test organic compound in 30 minutes at neutral pH and room temperature. By using X‐ray absorption spectroscopic techniques it is also shown that the superior activity of the nanocatalyst can be attributed uniquely to framework manganese, which decomposes H2O2 to reactive hydroxyls and, unlike manganese in Mn3O4 or Mn2O3 nanoparticles, does not promote the simultaneous decomposition of hydrogen peroxide. The presented material thus introduces a new family of Fenton nanocatalysts, which are environmentally friendly, cost‐effective, and possess superior efficiency for the decomposition of H2O2 to reactive hydroxyls (AOP), which in turn readily decompose organic pollutants dissolved in water.

Catalytic oxidation is one of the most important industrially applicable processes for the decomposition of volatile organic compounds (VOCs) in polluted air. The advanced VOC removal process is composed of an adsorption unit and a catalytic incinerator. Many efforts have been made to design a combined adsorption–catalytic unit with optimal activity and selectivity. We demonstrate that iron‐functionalized silica nanoparticles with interparticle mesoporosity (FeKIL‐2) act as highly efficient adsorbents and catalysts with optimal Fe/Si molar ratios of 0.01 in toluene oxidation as model VOCs in the gas phase. By using UV/Vis, FTIR, and Mössbauer spectroscopic techniques, we prove that the enhanced activity of the catalyst is attributed to iron incorporated into the silica matrix, which depends on the iron content. The iron content with Fe/Si≤0.01 leads to the formation of stable Fe3+ ions in the silica matrix, which ensures easier oxygen release from the catalyst (Fe3+/Fe2+ redox cycles). The increase in the iron content with Fe/Si>0.01 leads to the formation of oligonuclear iron complexes. The material thus introduces a promising, environmentally friendly, cost‐effective, and highly efficient catalyst with combined adsorption and catalytic properties for the removal of low‐concentration VOC from polluted air.

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Copper‐supported catalysts are of industrial importance in many catalytic processes. Mesoporous silica materials are of particular interest as green heterogeneous catalyst supports. In the present study we demonstrate the nature and reduction properties of copper oxide species, which are influenced by the peculiarity of the silica nanoparticles with interparticle mesoporosity (KIL family) and the presence of a second metal (iron) in the silica matrix. The copper‐containing KIL‐2 and FeKIL‐2 samples are prepared by incipient wetness impregnation. The reduction of copper oxide species is easier on the FeKIL‐2 supported sample in comparison to its KIL‐2 supported analogue, whereas the copper‐containing KIL‐2 sample shows higher catalytic activity in total toluene oxidation. The presence of iron in the FeKIL‐2 structure leads to autoreduction of copper followed by the redispersion and oxidation of metallic copper in the reaction medium; this results in the formation of different types of finely dispersed copper oxide species (<100 nm). The later species possess lower catalytic activity in toluene oxidation in comparison to species that are 100 nm in size and formed on KIL‐2.