Qiu Jiasi, Kuang Xiaoyu, Yu Miao, Xing Zhangyao, Zhou Siyuan, Chen Jichao, Ma Jiancheng, Mao Aijie
Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
Phys Chem Chem Phys. 2022 Sep 21;24(36):22038-22045. doi: 10.1039/d2cp02162e.
First-principles calculations are carried out to investigate the structural, electronic, and optical properties of CsGeCl. The results indicate that CsGeCl undergoes three structural phase transitions from or 3 to 3̄ at 8.5 GPa, from 3̄ to ppPv- at 9.4 GPa, and from ppPv- to 4 at 64 GPa, respectively. Meanwhile, the relation between the band gap and pressure implies that the band gap value of ppPv- is 1.56 eV at 40 GPa, making it a potential photovoltaic material. Based on pressure-induced stable structures, the CsGeCl quantum dots (QDs) have been fabricated to investigate the excited-state properties by tuning ultrafast laser pulses based on time-dependent density functional theory (TDDFT). The excited-state properties show that CsGeCl QDs have a wider absorption range compared with their bulk materials and their optical responses can be regulated by changing the laser intensity and wavelength. Our results further reveal that the 3-QDs exhibit excellent optical performance and have potential applications in optoelectronic devices.
进行第一性原理计算以研究CsGeCl的结构、电子和光学性质。结果表明，CsGeCl分别在8.5 GPa时从 或3相转变为3̄相，在9.4 GPa时从3̄相转变为ppPv-相，在64 GPa时从ppPv-相转变为4相。同时，带隙与压力之间的关系表明，在40 GPa时ppPv-的带隙值为1.56 eV，使其成为一种潜在的光伏材料。基于压力诱导的稳定结构，通过基于含时密度泛函理论（TDDFT）调谐超快激光脉冲，制备了CsGeCl量子点（QDs）以研究其激发态性质。激发态性质表明，与体材料相比，CsGeCl量子点具有更宽的吸收范围，并且其光学响应可以通过改变激光强度和波长来调节。我们的结果进一步表明，3-QDs表现出优异的光学性能，在光电器件中具有潜在应用。
