The characteristics of Cu-doped lead apatite (LK-99) synthesized with the removal of Cu2S using ammonia solution: A diamagnetic semiconductor
Source abstract
Abstract
This study evaluated the superconducting properties of Cu-doped lead apatite “LK-99” and synthesized LK-99 samples using the process proposed by a team from Korea, who first described the process. Additionally, whether the results of this Korean team were related to Cu2S was also examined using an ammonia solution (NH3·H2O) to remove Cu2S. Through x-ray diffraction (XRD) and energy dispersive x-ray spectroscopy (EDX) analyses, a distinct Cu2S phase was identified in the LK-99 samples. This phase was effectively eliminated through a subsequent treatment using an ammonia solution. The appearance of blue Cu+2 ions in the solution and the elimination of the Cu2S peak in XRD supported the conclusion. The magnetic and electrical properties of LK-99 with and without Cu2S suggest that the superconductor-like behavior in LK-99 predominantly arises from a transition in resistivity due to the influence of Cu2S. As such, LK-99 is better classified as a diamagnetic semiconductor than a room-temperature superconductor. The room-temperature superconductors still require further research.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Quantum Dots Synthesis And Properties · Copper-based nanomaterials and applications · Chalcogenide Semiconductor Thin Films
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Physics/Graduate Institute of Applied Physics, National Taiwan University 1 , Taipei 106, Taiwan
Instrumentation Center, National Taiwan University 2 , Taipei 106, Taiwan
Department of Materials Science and Engineering, Da-Yeh University 3 , Changhua 515, Taiwan
Funding
National Science and Technology Council
References (20)
Show source-provided references
1. S. Lee , J.-H.Kim, and Y.-W.Kwon, “The first room-temperature ambient-pressure superconductor,” arXiv:2307.12008 (2023).
2. S. Lee , J.Kim, H.-T.Kim, S.Im, S.An, and K. H.Auh, “Superconductor Pb10−xCux(PO4)6O showing levitation at room temperature and atmospheric pressure and mechanism,” arXiv:2307.12037 (2023).
3. S. M. Griffin , “Origin of correlated isolated flat bands in copper-substituted lead phosphate apatite,” arXiv:2307.16892 (2023).
4. I. Panas , “Entertaining the possibility of RT superconductivity in LK-99,” arXiv:2308.06684 (2023).
5. H. Oh and Y.-H.Zhang, “S-wave pairing in a two-orbital t-J model on triangular lattice: Possible application to Pb10−xCux(PO4)6O,” arXiv:2308.02469 (2023).
6. R. Kurleto , S.Lany, D.Pashov, S.Acharya, M.van Schilfgaarde, and D. S.Dessau, “Pb-apatite framework as a generator of novel flat-band CuO based physics, including possible room temperature superconductivity,” arXiv:2308.00698 (2023).
7. L. Hao and E.Fu, “First-principles calculation on the electronic structures, phonon dynamics, and electrical conductivities of Pb10(PO4)6O and Pb9Cu(PO4)6 compounds,” arXiv:2308.05618 (2023).10.1016/j.jmst.2023.08.010 ↗
8. C. Yue , V.Christiansson, and P.Werner, “Correlated electronic structure of Pb10−xCux(PO4)6O,” arXiv:2308.04976 (2023).
9. K. Tao , R.Chen, L.Yang, J.Gao, D.Xue, and C.Jia, “The 1/4 occupied O atoms induced ultraflat band and the one dimensional channels in the Pb10−xCux(PO4)6O4 (x = 0,0.5) crystal,” arXiv:2308.03218 (2023).10.1063/5.0188943 ↗
10. J. Cabezas-Escares , N. F.Barrera, R. H.Lavroff, A. N.Alexandrova, C.Cardenas, and F.Munoz, “Theoretical insight on the LK-99 material,” arXiv:2308.01135 (2023).
11. Y. Jiang , S. B.Lee, J.Herzog-Arbeitman, J.Yu, X.Feng, H.Hu, D.Călugăru, P. S.Brodale, E. L.Gormley, and M. G.Vergniory, “Pb9Cu(PO4)6(OH)2: Phonon bands, localized flat band magnetism, models, and chemical analysis,” arXiv:2308.05143 (2023).
12. C. Liu , W.Cheng, X.Zhang, J.Xu, J.Li, Q.Shi, C.Yuan, L.Xu, H.Zhou, and S.Zhu, “Phases and magnetism at microscale in compounds containing nominal Pb10−xCux(PO4)6O,” arXiv:2308.07800 (2023).
13. G. S. Thakur , M.Schulze, and M.Ruck, “On the synthesis methodologies to prepare Pb9Cu(PO4)6O phase, composition, magnetic analysis and absence of superconductivity,” arXiv:2308.05776 (2023).10.1088/1361-6668/ad1250 ↗
14. Phase transition of copper(I) sulfide and its implication for purported superconductivity of LK-9910.1021/acs.jpcc.3c05684 ↗
15. H. Wu , L.Yang, J.Yu, G.Zhang, B.Xiao, and H.Chang, “Observation of abnormal resistance-temperature behavior along with diamagnetic transition in Pb10−xCux(PO4)6O-based composite,” arXiv:2308.05001 (2023).
16. First order transition in Pb10−xCux(PO4)6O(0.9< x < 1.1) containing Cu2S10.1016/j.matt.2023.11.001 ↗
17. Synthesis and thermoelectric properties of copper sulfides via solution phase methods and spark plasma sintering10.3390/cryst7050141 ↗
18. Synthesis and characterization of Cu2S nanoparticles by diethylenetriamine-assisted hydrothermal method10.1016/j.ijleo.2015.09.203 ↗
19. LK-99 isn’t a superconductor—How science sleuths solved the mystery10.1038/d41586-023-02585-7 ↗
20. Single crystal synthesis, structure, and magnetism of Pb10−xCux(PO4)6O10.1063/5.0172755 ↗