Park, Seong Gon Lee, Kyu Hyoung Lee, Jae-Hoon Bang, Geukchan Kim, Junghwan Park, Hee Jung Oh, Min Suk Lee, Suyoun Kim, Young-Hoon Kim, Young-Min Hosono, Hideo Bang, Joonho Lee, Kimoon 2024-01-19T18:03:15Z 2024-01-19T18:03:15Z 2021-09-05 2020-02-21 2052-1553 https://pubs.kist.re.kr/handle/201004/118943 The origin of the electrical and optical properties of Cu-substituted NiO (Cu : NiO) polycrystalline bulks synthesized via a solid-state reaction is reported. The partial substitution of Ni sites with Cu led to a drastic decrease of the electrical resistivity from 7.73 x 10(8) to 6.51 x 10(4) Omega cm and a reduction in the energy for the self-trapping barrier from 0.58 to 0.24 eV in accordance with small polaron hopping conduction. The well-sustained band gap of 3.1 eV and antiferromagnetic transition temperature of 453 K demonstrate that the strength of the electron correlation in NiO can persist even at a high Cu concentration up to 22 atomic percent. Density functional theory calculations confirm that the Cu 3d orbital encourages d-p hybridization between metal cations and oxygen anions at the valence band maximum. As a consequence, this hybridization plays a critical role in improving the polaron hopping efficiency without much suppression of the Mott-Hubbard interaction and thus retaining the wide band gap nature. English ROYAL SOC CHEMISTRY TEMPERATURE CONDUCTION Improved polaronic transport under a strong Mott-Hubbard interaction in Cu-substituted NiO Article 10.1039/c9qi01052a 1 INORGANIC CHEMISTRY FRONTIERS, v.7, no.4, pp.853 - 858 INORGANIC CHEMISTRY FRONTIERS 7 4 853 858 scie scopus 000515601600023 2-s2.0-85080032853 Chemistry, Inorganic & Nuclear Chemistry Article TEMPERATURE CONDUCTION