Open AccessMetal‐to‐Semiconductor Transition and Electronic Dimensionality Reduction of Ca 2 N Electride under Pressure
Author(s) -
Tang Hu,
Wan Biao,
Gao Bo,
Muraba Yoshinori,
Qin Qin,
Yan Bingmin,
Chen Peng,
Hu Qingyang,
Zhang Dongzhou,
Wu Lailei,
Wang Mingzhi,
Xiao Hong,
Gou Huiyang,
Gao Faming,
Mao Hokwang,
Hosono Hideo
Publication year - 2018
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201800666
Subject(s) - semiconductor , materials science , phase (matter) , phase transition , chemical physics , electron , density functional theory , electrical resistance and conductance , electronic structure , transition metal , condensed matter physics , chemistry , optoelectronics , computational chemistry , catalysis , physics , organic chemistry , biochemistry , quantum mechanics , composite material
The discovery of electrides, in particular, inorganic electrides where electrons substitute anions, has inspired striking interests in the systems that exhibit unusual electronic and catalytic properties. So far, however, the experimental studies of such systems are largely restricted to ambient conditions, unable to understand their interactions between electron localizations and geometrical modifications under external stimuli, e.g., pressure. Here, pressure‐induced structural and electronic evolutions of Ca 2 N by in situ synchrotron X‐ray diffraction and electrical resistance measurements, and density functional theory calculations with particle swarm optimization algorithms are reported. Experiments and computation are combined to reveal that under compression, Ca 2 N undergoes structural transforms from R3 ¯m symmetry to I4 ¯ 2 d phase via an intermediate Fd3 ¯m phase, and then to Cc phase, accompanied by the reductions of electronic dimensionality from 2D, 1D to 0D. Electrical resistance measurements support a metal‐to‐semiconductor transition in Ca 2 N because of the reorganizations of confined electrons under pressure, also validated by the calculation. The results demonstrate unexplored experimental evidence for a pressure‐induced metal‐to‐semiconductor switching in Ca 2 N and offer a possible strategy for producing new electrides under moderate pressure.