Low Temperature Synthesis of 2D <i>p</i>‐Type <i>α‐</i>In<sub>2</sub>Te<sub>3</sub> with Fast and Broadband Photodetection
Ying Huangfu, Biao Qin, Ping Lu, Qiankun Zhang, Wei Li, Jingyi Liang, Zhaoming Liang, Jialing Liu, Miao Liu, Xiaohui Lin, Xu Li, Muhammad Zeeshan Saeed, Zhengwei Zhang, Jia Li, Bo Li, Xidong Duan
Abstract
Abstract 2D compounds (A = Al, Ga, In, and B = S, Se, and Te) with intrinsic structural defects offer significant opportunities for high‐performance and functional devices. However, obtaining 2D atomic‐thin nanoplates with non‐layered structure on SiO 2 /Si substrate at low temperatures is rare, which hinders the study of their properties and applications at atomic‐thin thickness limits. In this study, the synthesis of ultrathin, non‐layered α ‐In 2 Te 3 nanoplates is demonstrated using a BiOCl‐assisted chemical vapor deposition method at a temperature below 350 °C on SiO 2 /Si substrate. Comprehensive characterization results confirm the high‐quality single crystal is the low‐temperature cubic phase α ‐In 2 Te 3 , possessing a noncentrosymmetric defected ZnS structure with good second harmonic generation. Moreover, α‐ In 2 Te 3 is revealed to be a p ‐type semiconductor with a direct and narrow bandgap value of 0.76 eV. The field effect transistor exhibits a high mobility of 18 cm 2 V −1 s −1 , and the photodetector demonstrates stable photoswitching behavior within a broadband photoresponse from 405 to 1064 nm, with a satisfactory response time of τ rise = 1 ms. Notably, the α‐ In 2 Te 3 nanoplates exhibit good stability against ambient environments. Together, these findings establish α ‐In 2 Te 3 nanoplates as promising candidates for next‐generation high‐performance photonics and electronics.