US 12,325,814 B2
Luminescent diamond
J. Daniel Belnap, Provo, UT (US)
Assigned to SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US)
Appl. No. 17/421,403
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US)
PCT Filed Jan. 15, 2020, PCT No. PCT/US2020/013664
§ 371(c)(1), (2) Date Jul. 8, 2021,
PCT Pub. No. WO2020/150341, PCT Pub. Date Jul. 23, 2020.
Claims priority of provisional application 62/793,032, filed on Jan. 16, 2019.
Prior Publication US 2022/0056337 A1, Feb. 24, 2022
Int. Cl. C09K 11/65 (2006.01); C01B 32/28 (2017.01)
CPC C09K 11/65 (2013.01) [C01B 32/28 (2017.08); C01P 2002/54 (2013.01); C01P 2002/60 (2013.01); C01P 2004/61 (2013.01); C01P 2004/62 (2013.01); C01P 2004/64 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for making luminescent diamond comprising:
subjecting a volume of precursor diamond grains to a high-pressure/high-temperature condition to cause the precursor diamond grains to undergo plastic deformation to produce a volume of resulting diamond grains containing nitrogen vacancy defects, wherein the resulting diamond grains display a level of luminescence intensity that is greater than that of the precursor diamond grains;
subsequently reducing the size of the resulting diamond grains via a size reducing treatment wherein the resulting diamond grains undergo plastic deformation or fracture, thereby producing luminescent diamond grains having an average diameter size of less than 20 μm, wherein the luminescent diamond grains display a level of luminescence intensity that is greater than that of the resulting diamond grains; and
exposing the luminescent diamond grains to an oxidizing heat treatment in air, thereby increasing the level of luminescence intensity of the luminescent diamond grains.