Size-controlled ex-nihilo ferromagnetism in capped CdSe quantum dots

Mohindar S. Seehra, Prasanta Dutta, Sonnathi Neeleshwar, Yang Yuan Chen, Cheng Lung Chen, Shang Wei Chou, Chia Chun Chen, Chung Li Dong, Ching Lin Chang

Research output: Contribution to journalArticle

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Abstract

The observation of RTEM in CdSe quantum dots (QD) capped with TOPO was investigated. XPS and EXAFS studies on TOPO passivated CdSe QDs have shown that TOPO binds only at the Cd site and that the surface coverage on the Cd sites varies from a high of about 60% for D=2 nm to about 35% for D>3 nm. The mechanism of charge transfer from Cd to TOPO invoked in the interpretation was measured in some of the samples using XANES (X-ray absorption near-edge structure) and EXAFS (extended X-ray absorption fine structure) spectra of TOPO-capped CdSe QDs. It was observed that with the reduction in size D of the CdSe QDs, an increase in the d-hole population of the Cd 4d band is possible as a result of the charge redistribution with the capping agent TOPO.

Original languageEnglish
Pages (from-to)1656-1660
Number of pages5
JournalAdvanced Materials
Volume20
Issue number9
DOIs
Publication statusPublished - 2008 May 5

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Ferromagnetism
X ray absorption
Semiconductor quantum dots
Charge transfer
X ray photoelectron spectroscopy
trioctyl phosphine oxide

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Seehra, M. S., Dutta, P., Neeleshwar, S., Chen, Y. Y., Chen, C. L., Chou, S. W., ... Chang, C. L. (2008). Size-controlled ex-nihilo ferromagnetism in capped CdSe quantum dots. Advanced Materials, 20(9), 1656-1660. https://doi.org/10.1002/adma.200702382

Size-controlled ex-nihilo ferromagnetism in capped CdSe quantum dots. / Seehra, Mohindar S.; Dutta, Prasanta; Neeleshwar, Sonnathi; Chen, Yang Yuan; Chen, Cheng Lung; Chou, Shang Wei; Chen, Chia Chun; Dong, Chung Li; Chang, Ching Lin.

In: Advanced Materials, Vol. 20, No. 9, 05.05.2008, p. 1656-1660.

Research output: Contribution to journalArticle

Seehra, MS, Dutta, P, Neeleshwar, S, Chen, YY, Chen, CL, Chou, SW, Chen, CC, Dong, CL & Chang, CL 2008, 'Size-controlled ex-nihilo ferromagnetism in capped CdSe quantum dots', Advanced Materials, vol. 20, no. 9, pp. 1656-1660. https://doi.org/10.1002/adma.200702382
Seehra MS, Dutta P, Neeleshwar S, Chen YY, Chen CL, Chou SW et al. Size-controlled ex-nihilo ferromagnetism in capped CdSe quantum dots. Advanced Materials. 2008 May 5;20(9):1656-1660. https://doi.org/10.1002/adma.200702382
Seehra, Mohindar S. ; Dutta, Prasanta ; Neeleshwar, Sonnathi ; Chen, Yang Yuan ; Chen, Cheng Lung ; Chou, Shang Wei ; Chen, Chia Chun ; Dong, Chung Li ; Chang, Ching Lin. / Size-controlled ex-nihilo ferromagnetism in capped CdSe quantum dots. In: Advanced Materials. 2008 ; Vol. 20, No. 9. pp. 1656-1660.
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