10.1021/acs.chemmater.7b02029.s001
Theodore
E. G. Alivio
Theodore
E. G.
Alivio
Diane G. Sellers
Diane G.
Sellers
Hasti Asayesh-Ardakani
Hasti
Asayesh-Ardakani
Erick J. Braham
Erick J.
Braham
Gregory A. Horrocks
Gregory A.
Horrocks
Kate E. Pelcher
Kate E.
Pelcher
Ruben Villareal
Ruben
Villareal
Lucia Zuin
Lucia
Zuin
Patrick J. Shamberger
Patrick J.
Shamberger
Raymundo Arróyave
Raymundo
Arróyave
Reza Shahbazian-Yassar
Reza
Shahbazian-Yassar
Sarbajit Banerjee
Sarbajit
Banerjee
Postsynthetic Route for Modifying the MetalInsulator
Transition of VO<sub>2</sub> by Interstitial Dopant Incorporation
American Chemical Society
2017
VO 2
postsynthetic dopant incorporation
phase diagram
Local structure studies
novel postsynthetic diffusive annealing approach
theory calculations point
equilibrium transition temperature
phase transition material
transition temperature
modulating
Interstitial Dopant Incorporation
2017-05-24 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Postsynthetic_Route_for_Modifying_the_Metal_Insulator_Transition_of_VO_sub_2_sub_by_Interstitial_Dopant_Incorporation/5077852
The
thermally driven orders-of-magnitude modulation of resistance
and optical transmittance observed in VO<sub>2</sub> makes it an archetypal
first-order phase transition material and underpins functional applications
in logic and memory circuitry, electromagnetic cloaking, ballistic
modulation, and thermochromic glazing to provide just a few representative
examples. VO<sub>2</sub> can be reversibly switched from an insulating
to a metallic state at an equilibrium transition temperature of 67
°C. Tuning the phase diagram of VO<sub>2</sub> to bring the transition
temperature closer to room temperature has been a longstanding objective
and one that has tremendous practical relevance. Substitutional incorporation
of dopants has been the most common strategy for modulating the metalinsulator
transition temperature but requires that the dopants be incorporated
during synthesis. Here we demonstrate a novel postsynthetic diffusive
annealing approach for incorporating interstitial B dopants within
VO<sub>2</sub>. The postsynthetic method allows for the transition
temperature to be programmed after synthesis and furthermore represents
an entirely distinctive mode of modulating the phase diagram of VO<sub>2</sub>. Local structure studies in conjunction with density functional
theory calculations point to the strong preference of B atoms for
tetrahedral coordination within interstitial sites of VO<sub>2</sub>; these tetrahedrally coordinated dopant atoms hinder the rutile
→ monoclinic transition by impeding the dimerization of V–V
chains and decreasing the covalency of the lattice. The results suggest
that interstitial dopant incorporation is a powerful method for modulating
the transition temperature and electronic instabilities of VO<sub>2</sub> and provides a facile approach for postsynthetic dopant incorporation
to reach a switching temperature required for a specific application.