title: Atomistic Insights into the Oriented Attachment of Tunnel-Based Oxide Nanostructures.
abstract: Controlled synthesis of nanomaterials is one of the grand challenges facing materials scientists. In particular, how tunnel-based nanomaterials aggregate during synthesis while maintaining their well-aligned tunneled structure is not fully understood. Here, we describe the atomistic mechanism of oriented attachment (OA) during solution synthesis of tunneled α-MnO2 nanowires based on a combination of in situ liquid cell transmission electron microscopy (TEM), aberration-corrected scanning TEM with subangstrom spatial resolution, and first-principles calculations. It is found that primary tunnels (1 × 1 and 2 × 2) attach along their common {110} lateral surfaces to form interfaces corresponding to 2 × 3 tunnels that facilitate their short-range ordering. The OA growth of α-MnO2 nanowires is driven by the stability gained from elimination of {110} surfaces and saturation of Mn atoms at {110}-edges. During this process, extra [MnOx] radicals in solution link the two adjacent {110} surfaces and bond with the unsaturated Mn atoms from both surface edges to produce stable nanowire interfaces. Our results provide insights into the controlled synthesis and design of nanomaterials in which tunneled structures can be tailored for use in catalysis, ion exchange, and energy storage applications.
authors.affiliation: Department of Materials Science and Engineering, Michigan Technological University , 1400 Townsend Drive, Houghton, Michigan 49931, United States.|Chemical Science and Engineering Division, Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States.
authors.forename: Yifei
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Department of Chemistry, University of Bath , Bath BA2 7AY, United Kingdom.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Wood
authors.affiliation: Department of Materials Science and Engineering, Michigan Technological University , 1400 Townsend Drive, Houghton, Michigan 49931, United States.|Department of Materials Science and Engineering, Shandong University , 17923 Jingshi Road, Jinan 250061, China.
authors.forename: Kun
authors.initials: K
authors.lastname: He
authors.affiliation: Department of Mechanical Engineering, Michigan Technological University , 1400 Townsend Drive, Houghton, Michigan 49931, United States.
authors.forename: Wentao
authors.initials: W
authors.lastname: Yao
authors.affiliation: Department of Chemistry, University of Bath , Bath BA2 7AY, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Tompsett
authors.affiliation: Chemical Science and Engineering Division, Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States.
authors.forename: Jun
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of Mechanical Engineering, Michigan Technological University , 1400 Townsend Drive, Houghton, Michigan 49931, United States.
authors.forename: Anmin
authors.initials: A
authors.lastname: Nie
authors.affiliation: Department of Chemistry, University of Bath , Bath BA2 7AY, United Kingdom.
authors.forename: M Saiful
authors.initials: MS
authors.lastname: Islam
authors.affiliation: Department of Mechanical Engineering, Michigan Technological University , 1400 Townsend Drive, Houghton, Michigan 49931, United States.|Department of Mechanical and Industrial Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States.
authors.forename: Reza
authors.initials: R
authors.lastname: Shahbazian-Yassar
keywords: interface; nanowire; oriented attachment; surface structure; tunnel