Heterogeneous conversion of SO₂on nano α-Fe₂O₃: the effects of morphology, light illumination and relative humidity

Abstract

Hematite is one of the most important components in atmospheric mineral aerosols, which always presents different morphologies due to its different formation processes and various sources.

A novel pathway of atmospheric sulfate formation through carbonate radicals

“…Fe 2 O 3 is also one of the crucial components found in authentic mineral dust (El Zein et al, 2013), and it has been reported to produce electron-hole pairs under solar irradiation (Li et al, 2019), thus likely involving the reaction channel considered in this work (see a detailed discussion in a later section). Similar to the protocol applied for synthesizing the TiO 2 + CaCO 3 mixture, αFe 2 O 3 + CaCO 3 are prepared accordingly.…”

Heterogeneous reaction of toluene/NO2/O3 on α-Fe2O3 nanoparticles: the impacts of O3, light illumination, and relative humidity on the formation of N-containing organic compounds (NOC)

“…Li et al suggested that the photoreduction of α-Fe 2 O 3 is probably not dominant under light. 50 From what was discussed above, it is concluded that simulated solar radiation promotes the formation rate of NOC from the reaction of toluene/NO 2 on the α-Fe 2 O 3 nanoparticles, while it becomes less noticeable under more complex pollution, i.e. , in the presence of O 3 .…”

“…These indicate that the formation processes of R-ONO 2 species can be classified into the initial stage and stable stage, which are consistent with the increasing trends of the product amounts obtained previously. 50 In the initial stage, due to the abundant reactive sites on the α-Fe 2 O 3 nanoparticles for the adsorption and oxidation of trace gases, the formation amounts of NOC increase very rapidly with reaction time under four different conditions. As the heterogeneous reactions proceed, the reactive sites on the surface of the α-Fe 2 O 3 nanoparticles are gradually consumed and covered by newly formed products.…”

Reply on RC1

“…By contrast, organic compounds, like CH 3 CHO (Zhao et al, 2015), HCOOH (Wu et al, 2013), CH 3 COOH (Yang et al, 2020;Wang et al, 2022) and C 3 H 6 (Chu et al, 2019), were found to suppress the interactions due to the accumulation or production of particle-phase organic acids. In terms of particle property, size (Baltrusaitis et al, 2010;Zhang et al, 2016), morphology (Li et al, 2019) and crystal structure (Yang et al, 2017) exhibit varied impacts. Among the common mineral constituents, Fe 2 O 3 is more efficient than Al 2 O 3 and SiO 2 (Chughtai et al, 1993;Zhang et al, 2006;He et al, 2014).…”