Title: In situ 3‐D mapping of pore structures and hollow grains of interplanetary dust particles with phase contrast X‐ray nanotomography

Abstract

Abstract Unlocking the 3‐D structure and properties of intact chondritic porous interplanetary dust particles ( IDP s) in nanoscale detail is challenging, which is also complicated by atmospheric entry heating, but is important for advancing our understanding of the formation and origins of IDP s and planetary bodies as well as dust and ice agglomeration in the outer protoplanetary disk. Here, we show that indigenous pores, pristine grains, and thermal alteration products throughout intact particles can be noninvasively visualized and distinguished morphologically and microstructurally in 3‐D detail down to ~10 nm by exploiting phase contrast X‐ray nanotomography. We have uncovered the surprisingly intricate, submicron, and nanoscale pore structures of a ~10‐μm‐long porous IDP , consisting of two types of voids that are interconnected in 3‐D space. One is morphologically primitive and mostly submicron‐sized intergranular voids that are ubiquitous; the other is morphologically advanced and well‐defined intragranular nanoholes that run through the approximate centers of ~0.3 μm or lower submicron hollow grains. The distinct hollow grains exhibit complex 3‐D morphologies but in 2‐D projections resemble typical organic hollow globules observed by transmission electron microscopy. The particle, with its outer region characterized by rough vesicular structures due to thermal alteration, has turned out tomore » be an inherently fragile and intricately submicron‐ and nanoporous aggregate of the sub‐μm grains or grain clumps that are delicately bound together frequently with little grain‐to‐grain contact in 3‐D space.« less

Authors:

Hu, Z. W. ^[1]; Winarski, R. P. ^[2]

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+ Show Author Affiliations

1. XNano Sciences Inc. P.O. Box 12852 Huntsville Alabama 35815 USA
2. Center for Nanoscale Materials Argonne National Laboratory Argonne Illinois 60439 USA

Publication Date:

Fri Jul 01 00:00:00 EDT 2016

Sponsoring Org.:

USDOE

OSTI Identifier:

1401446

Grant/Contract Number:  

DE‐AC02‐06CH11357

Resource Type:

Publisher's Accepted Manuscript

Journal Name:

Meteoritics and Planetary Science

Additional Journal Information:

Journal Name: Meteoritics and Planetary Science Journal Volume: 51 Journal Issue: 9; Journal ID: ISSN 1086-9379

Publisher:

Wiley-Blackwell

Country of Publication:

United States

Language:

English