Surface Composites Synthesized through the Incorporation of Atomic Layer Deposited AlOx into Nanoporous Fuzzy Tungsten

Li Cheng; Marlene Patino; Matthew J Baldwin; Prabhakar R Bandaru

doi:10.1021/acsami.3c18842

Surface Composites Synthesized through the Incorporation of Atomic Layer Deposited AlO_x into Nanoporous Fuzzy Tungsten

ACS Appl Mater Interfaces. 2024 Mar 20;16(11):14047-14054. doi: 10.1021/acsami.3c18842. Epub 2024 Mar 11.

Authors

Li Cheng¹, Marlene Patino², Matthew J Baldwin², Prabhakar R Bandaru¹

Affiliations

¹ Department of Mechanical Engineering, Program in Materials Science, University of California, San Diego, La Jolla, California 92093, United States.
² Center for Energy Research, University of California, San Diego, La Jolla, California 92093, United States.

PMID: 38466625
DOI: 10.1021/acsami.3c18842

Abstract

The incorporation of energetic helium gaseous species into materials such as tungsten (W) imparts intrinsic surface fragility, yielding fuzzy tungsten. To enhance the robustness of the surface layers, aluminum oxide (AlO_x) was deposited by atomic layer deposition into the fuzzy W. The conformally deposited ceramic yields a new class of surface composites. Structural characterization of the fuzzy W-AlO_x composites through nanoindentation testing indicated enhanced indentation modulus (E_ind) and hardness (H_ind) and was modeled through various rules of mixtures approaches. The distribution of AlO_x in fuzzy W was explored and a systematic study of the extent of incorporation of the AlO_x into the fuzzy W was carried out. The synthesized composites may be utilized for improved structural characteristics, e.g., in reducing crack initiation and fracture.

Keywords: aluminum oxide; atomic layer deposition; composites; fuzzy tungsten; indentation modulus; nanoporosity; structural integrity; surface layers.