Optically levitated, single-particle reactor for the study of surface and heterogeneous chemistry-reactions of particulate-bound mercury with ozone in air

• Published in: Chemical physics letters Vol. 817; p. 140428
• Main Authors: Ai, Yukai, Wang, Chuji, Videen, Gorden, Pan, Yong-Le
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 16.04.2023
• Subjects: Heterogeneous chemistry of mercury; Optical trapping; Ozone; Raman; Single-particle reactor; Heterogeneous chemistry of mercury; Optical trapping; Single-particle reactor; Ozone; Raman
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2023.140428

[Display omitted] •Optically-trapped, chemically-purposed, micron-sized, single-particle reactor (SPR) in air.•Heterogeneous reaction of solid-state Hg(II) halides on the surface SPR.•A new platform for the study of surface and heterogeneous chemistry of aerosol particles in air. We created a micron-sized, single-particle reactor (SPR) freely levitated in air using optical trapping of a single particulate-bound mercury particle formed by mixing HgCl2, HgBr2, or HgBrCl (HgX2, X = Cl, Br) with single-walled carbon nanotubes. Position- and time-resolved, single-particle Raman spectra show clear evidence of reactions of solid-state HgX2 in the presence of excessive O3 under the illumination of 532-nm light. We propose a reaction mechanism: Hg(II)X2 (solid) + O → Hg(I)X + XO, XO + O → O2 + X on the surface of the SPR. This exploratory study demonstrates that the SPR is a new tool for the study the surface and heterogeneous chemistry of mercury at atmospherically relevant surfaces, e.g., aerosols.