2D Nonlayered Selenium Nanosheets: Facile Synthesis, Photoluminescence, and Ultrafast Photonics. Issue 24 (20th November 2017)

• Record Type: Journal Article
• Authors: Xing, Chenyang; Xie, Zhongjian; Liang, Zhiming; Liang, Weiyuan; Fan, Taojian; Ponraj, Joice Sophia; Dhanabalan, Sathish Chander; Fan, Dianyuan; Zhang, Han
• Is Part Of: Advanced optical materials. Volume 5:Issue 24(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-11-20
• Subjects: 2D nonlayered materials -- 2D selenium -- chemical stability -- ultrafast photonics; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.201700884
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: Investigations into 2D nanomaterials are of considerable significance from both an academic and industrial point of view. The present work addresses, for the first time, the fabrication of 2D nonlayered ultrathin selenium through a facile liquid‐phase exfoliation method. The results reveal that the as‐prepared 2D Se nanosheets are 40–120 nm in lateral dimension and 3–6 nm in thickness. The nanosheets exhibit a trigonal crystalline phase similar to their bulk counterpart, indicating the conservation of the crystalline features during the exfoliation procedure. The successful preparation of 2D Se nanosheets from nonlayered bulk Se can be ascribed to two kinds of anisotropy: (1) that of crystalline bulk Se with chain‐like structures, where strong intrachain SeSe covalent bonds coexist with weak interchain van der Waals forces, and (2) that of probe sonication in the vertical direction. The results also show that the 2D Se nanosheets possess a size‐dependent band gap ( E g ), strong photoluminescence effect and robust, chemical stability under ambient conditions. Furthermore, a 2D Se‐nanosheet‐based optical modulation device is demonstrated that allows for excellent ultrashort pulse generation of an optical communication band. It is therefore anticipated that 2D Se nanosheets may find significant applications in both photoluminescence and ultrafast photonics. Abstract : In this work, 2D nonlayered selenium nanosheets are fabricated by virtue of the anisotropy of bulk Se itself and probe‐sonication liquid‐phase exfoliation. The morphology, band gap, optical absorption, crystalline phase, and chemical stability are investigated. Based on these characterizations, the 2D Se nanosheets are realized for ultrafast photonics, and their performance is evaluated.