2026-10-14T14:18:57Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33942938 2026-09-19T15:23:07Z category_4 category_146 category_7 category_19 category_21 category_272 category_873 category_39 category_502 category_734 category_69 category_113 portal_63 item_type_3 month_year_09_2026

Single-Particle Visualization of Water Uptake of Organic–Inorganic Aerosols with In Situ Transmission Electron Microscopy Martin C. Ahn (25076330) Yuhang Wang (332111) Amy Chen (263838) Dewansh Rastogi (13001594) Kotiba Malek (14784805) Liza-Anastasia DiCecco (14757043) Jennifer Gray (358138) Akua Asa-Awuku (544499) Taylor Woehl (16474678) Biochemistry Space Science Medicine Pharmacology Biotechnology Environmental Sciences not elsewhere classified Chemical Sciences not elsewhere classified Ecology Astronomical and Space Sciences not elsewhere classified Biological Sciences not elsewhere classified Inorganic Chemistry Plasma Physics uncover mechanistic details inorganic hygroscopic salts hygroscopic droplet growth elemental mapping revealed sodium extended beyond aerosol mixing state new phase formation residual pta core dehumidification effected precipitation amorphous pta domain water uptake dynamics partial nacl deliquescence nacl aerosols contained nacl nanocrystal formation situ </ italic situ </ water uptake sodium phthalate partial dissolution eutonic mixing aerosols proceeds via </ work solidifies particle visualization nonintuitive ways morphology changes made pta made particles humidity controlled heterogeneous nature global climate electron tomography chloride depletion chemical reactions bulk pta atmospheric chemistry Atmospheric aerosol water uptake properties influence cloud formation and precipitation, atmospheric chemistry, and global climate. Atmospheric aerosols often contain organic acids and inorganic hygroscopic salts, and their internal mixing influences water uptake properties in complex and nonintuitive ways. The heterogeneous nature of aerosol ensembles necessitates nanoscale visualization of aerosol mixing state and water uptake dynamics to uncover mechanistic details. Here we demonstrate that water uptake in phase separated phthalic acid (PTA)/sodium chloride (NaCl) aerosols proceeds by eutonic mixing and partial NaCl deliquescence, while subsequent drying creates core–shell particles containing newly formed sodium phthalate salts. Electron tomography and elemental mapping revealed that lab-made PTA/NaCl aerosols contained a cuboidal crystalline NaCl domain and amorphous PTA domain. Sodium extended beyond the NaCl into a ∼10 nm thick chemically distinct interphase between NaCl and the bulk PTA, consistent with formation of sodium phthalate <i>via</i> chloride depletion. Humidity controlled <i>in situ</i> TEM imaging revealed PTA/NaCl aerosols initially uptake water by adsorption and swelling of the PTA. Further increases in humidity caused partial NaCl deliquescence, hygroscopic droplet growth, and partial dissolution and morphology changes in the PTA. Dehumidification effected precipitation of an organic-rich solid shell followed by NaCl nanocrystal formation on the residual PTA core, yielding a distinctly different core–shell morphology compared to the as-made particles. Diffraction and elemental mapping confirm crystalline sodium acid phthalate forms following dehumidification. This work solidifies our understanding of water uptake and chemical reactions in mixed organic–inorganic atmospheric aerosols by uncovering multistep water uptake dynamics and new phase formation. 2026-09-19T00:00:00Z Dataset Dataset 10.1021/acsestair.6c00332.s002 https://figshare.com/articles/dataset/Single-Particle_Visualization_of_Water_Uptake_of_Organic_Inorganic_Aerosols_with_In_Situ_Transmission_Electron_Microscopy/33942938 CC BY-NC 4.0