Oxygen Vacancy Induced Room-Temperature Metal-Insulator Transition in Nickelate Films and Its Potential Application in Photovoltaics

Le Wang, Sibashisa Dash, Lei Chang, Lu You, Yaqing Feng, Xu He, Kui Juan Jin, Yang Zhou, Hock Guan Ong, Peng Ren, Shiwei Wang, Lang Chen, Junling Wang

Research output: Contribution to journalArticle

42 Citations (Scopus)

Abstract

(Graph Presented) Oxygen vacancy is intrinsically coupled with magnetic, electronic, and transport properties of transition-metal oxide materials and directly determines their multifunctionality. Here, we demonstrate reversible control of oxygen content by postannealing at temperature lower than 300 °C and realize the reversible metal-insulator transition in epitaxial NdNiO3 films. Importantly, over 6 orders of magnitude in the resistance modulation and a large change in optical bandgap are demonstrated at room temperature without destroying the parent framework and changing the p-type conductive mechanism. Further study revealed that oxygen vacancies stabilized the insulating phase at room temperature is universal for perovskite nickelate films. Acting as electron donors, oxygen vacancies not only stabilize the insulating phase at room temperature, but also induce a large magnetization of ∼50 emu/cm3 due to the formation of strongly correlated Ni2+ t2g 6eg 2 states. The bandgap opening is an order of magnitude larger than that of the thermally driven metal-insulator transition and continuously tunable. Potential application of the newly found insulating phase in photovoltaics has been demonstrated in the nickelate-based heterojunctions. Our discovery opens up new possibilities for strongly correlated perovskite nickelates.

Original languageEnglish
Pages (from-to)9769-9776
Number of pages8
JournalACS Applied Materials and Interfaces
Volume8
Issue number15
DOIs
Publication statusPublished - 2016 Apr 20
Externally publishedYes

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Keywords

  • heterojunction
  • metal-insulator transition
  • nickelate thin films
  • oxygen vacancy
  • photovoltaics

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Wang, L., Dash, S., Chang, L., You, L., Feng, Y., He, X., Jin, K. J., Zhou, Y., Ong, H. G., Ren, P., Wang, S., Chen, L., & Wang, J. (2016). Oxygen Vacancy Induced Room-Temperature Metal-Insulator Transition in Nickelate Films and Its Potential Application in Photovoltaics. ACS Applied Materials and Interfaces, 8(15), 9769-9776. https://doi.org/10.1021/acsami.6b00650