Premium
Wide Band Gap Organic–Inorganic Hybrid (CH 3 NH 3 ) 2 HgCl 4 as Self‐Driven Ultraviolet Photodetector and Photoconductor
Author(s) -
Yu Ning,
Tao Siwen,
Cui Jiawen,
Zhou Huawei,
Chen Yan,
Cui Shuting,
Gao Xiaorui,
Yin Jie,
Liu Xuejing,
Zhang Xianxi
Publication year - 2020
Publication title -
applied organometallic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.53
H-Index - 71
eISSN - 1099-0739
pISSN - 0268-2605
DOI - 10.1002/aoc.5982
Subject(s) - chemistry , monoclinic crystal system , band gap , ultraviolet , photoelectric effect , crystal (programming language) , single crystal , analytical chemistry (journal) , photodetector , photoconductivity , crystal structure , optoelectronics , crystallography , materials science , computer science , programming language , chromatography
At present, developing new organic–inorganic hybrid materials (OIHM) and studying their photoelectric properties is an important research field. In this work, the OIHM (CH 3 NH 3 ) 2 HgCl 4 (MA 2 HgCl 4 ) single crystal and thin film are prepared. The results show that the crystal structure of MA 2 HgCl 4 has a monoclinic crystal system with P2 1 /c (14) space group (unit cell dimensions 7.776 × 12.917 × 10.993 Å, 90.00 × 96.366 × 90.00) by solving the single crystal diffraction data. The band gap of MA 2 HgCl 4 is calculated to be approximately 3.21 eV. To the best of our knowledge, this is the first study on MA 2 HgCl 4 for optoelectronic application. The photodetector based on MA 2 HgCl 4 thin film is highly selective for ultraviolet (UV) light (369 nm), and has a poor response for visible light. The electrochemical impedance spectrum shows that the impedance value (2 kΩ) of the device under 369 nm UV light is four magnitudes lower than that (10 7 Ω) under dark. Thus, MA 2 HgCl 4 has the nature of a photoconductor. The density functional theory indicates that the valence band maximum (VBM) of MA 2 HgCl 4 is mainly derived from Cl‐3p state, Hg‐5d state and organic CH 3 NH 3 + state also participate in the formation of the VBM band. The electron states of VBM and the conduction band minimum of MA 2 HgCl 4 come from inorganic HgCl 4 2− clusters.