Real-time atomistic observation of structural phase transformations in individual hafnia nanorods

Nature Communications
Bethany M HudakBeth S Guiton

Abstract

High-temperature phases of hafnium dioxide have exceptionally high dielectric constants and large bandgaps, but quenching them to room temperature remains a challenge. Scaling the bulk form to nanocrystals, while successful in stabilizing the tetragonal phase of isomorphous ZrO2, has produced nanorods with a twinned version of the room temperature monoclinic phase in HfO2. Here we use in situ heating in a scanning transmission electron microscope to observe the transformation of an HfO2 nanorod from monoclinic to tetragonal, with a transformation temperature suppressed by over 1000°C from bulk. When the nanorod is annealed, we observe with atomic-scale resolution the transformation from twinned-monoclinic to tetragonal, starting at a twin boundary and propagating via coherent transformation dislocation; the nanorod is reduced to hafnium on cooling. Unlike the bulk displacive transition, nanoscale size-confinement enables us to manipulate the transformation mechanism, and we observe discrete nucleation events and sigmoidal nucleation and growth kinetics.

References

Aug 15, 1989·Physical Review. B, Condensed Matter·M Methfessel, A T Paxton
Jun 15, 1994·Physical Review. B, Condensed Matter·P E BlöchlO K Andersen
Jun 6, 2003·Journal of the American Chemical Society·Jin JooTaeghwan Hyeon
Jul 8, 2005·Nature·Steven C ErwinDavid J Norris
Jun 29, 2006·Physical Review Letters·Gustavo M Dalpian, James R Chelikowsky
Jan 24, 2009·Microscopy Research and Technique·Lawrence F AllardStephen E Mick
Jul 12, 2011·Chemphyschem : a European Journal of Chemical Physics and Physical Chemistry·Alexandra Navrotsky
Aug 22, 2014·Scientific Reports·Xu-Sheng YangTong-Yi Zhang
Jun 16, 2015·Journal of the American Chemical Society·Shu-Hui GuanZhi-Pan Liu

❮ Previous
Next ❯

Citations

Feb 28, 2019·Advanced Materials·Xiaoxu ZhaoKian Ping Loh
Jun 6, 2020·Microscopy and Microanalysis : the Official Journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada·Berit H GoodgeLena F Kourkoutis
Oct 28, 2020·Small·Md Sohel RanaKun Qian
Aug 14, 2020·Journal of the American Chemical Society·Diane G SellersSarbajit Banerjee

❮ Previous
Next ❯

Methods Mentioned

BETA
X-ray
chips

Software Mentioned

CrystalMaker
QSTEM
ATAT
Adobe Photoshop
Protochips Aduro
Vienna ab initio simulation package

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.