Relationship between Co-related optical centres and nitrogen impurities in large single crystals of diamond grown in Co–C system under HPHT conditions

Abstract

In this paper, large single crystals of diamond were synthesized in a pure Co–C system at 5.6 GPa and 1450–1470 °C. The diamond morphology, nitrogen content, and Co-related optical centres were investigated in depth. The results show that the diamonds are mostly bicrystalline or polycrystalline, with different surface defects, and the grown single crystals exhibit an octahedral morphology, with primarily {111} faces. The colour of the diamonds is brownish green-yellow and the nitrogen content is up to 980 ppm. The photoluminescence (PL) spectra show the presence of Co–V centres at 623 nm (V3Co2)0 and 843 nm (V1Co1+) in the diamonds. The intensity of Co-related optical centres at 623 nm and 843 nm gradually decreased with increases in the annealing temperature, and finally disappeared. Interestingly, Co–N complex defects appeared at 545 nm and 581 nm after annealing at 1700 °C, and the 524 nm Co–N complexes only appeared when the nitrogen almost completely aggregated after annealing up to 1800–1900 °C, and their intensity gradually increased with increasing annealing temperature. Furthermore, when nitrogen was removed from the growth system, the Co-related optical centres did not appear in the type IIa diamonds before and after annealing, which indicates that nitrogen impurities play an important role in the formation of Co-related optical centres.

Graphical abstract: Relationship between Co-related optical centres and nitrogen impurities in large single crystals of diamond grown in Co–C system under HPHT conditions

Article information

Article type
Paper
Submitted
31 Aug 2022
Accepted
22 Nov 2022
First published
24 Nov 2022

CrystEngComm, 2023, Advance Article

Relationship between Co-related optical centres and nitrogen impurities in large single crystals of diamond grown in Co–C system under HPHT conditions

Y. Song, C. Fang, Y. Mu, Y. Li, W. Shen, Z. Zhang, Y. Zhang, Q. Wang, B. Wan, L. Chen and X. Jia, CrystEngComm, 2023, Advance Article , DOI: 10.1039/D2CE01197B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements