Hydrogen Terminated Germanene for a Robust Self‐Powered Flexible Photoelectrochemical Photodetector. Issue 23 (10th May 2020)

• Record Type: Journal Article
• Authors: Liu, Nana; Qiao, Hui; Xu, Kang; Xi, Yilian; Ren, Long; Cheng, Ningyan; Cui, Dandan; Qi, Xiang; Xu, Xun; Hao, Weichang; Dou, Shi Xue; Du, Yi
• Is Part Of: Small. Volume 16:Issue 23(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-05-10
• Subjects: 2D materials -- germanane -- germanene -- photoelectrochemical photodetectors; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202000283
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: As a rising star in the family of graphene analogues, germanene shows great potential for electronic and optical device applications due to its unique structure and electronic properties. It is revealed that the hydrogen terminated germanene not only maintains a high carrier mobility similar to that of germanene, but also exhibits strong light–matter interaction with a direct band gap, exhibiting great potential for photoelectronics. In this work, few‐layer germanane (GeH) nanosheets with controllable thickness are successfully synthesized by a solution‐based exfoliation–centrifugation route. Instead of complicated microfabrication techniques, a robust photoelectrochemical (PEC)‐type photodetector, which can be extended to flexible device, is developed by simply using the GeH nanosheet film as an active electrode. The device exhibits an outstanding photocurrent density of 2.9 µA cm −2 with zero bias potential, excellent responsivity at around 22 µA W −1 under illumination with intensity ranging from 60 to 140 mW cm −2, as well as short response time (with rise and decay times, t r = 0.24 s and t d = 0.74 s). This efficient strategy for a constructing GeH‐based PEC‐type photodetector suggests a path to promising high‐performance, self‐powered, flexible photodetectors, and it also paves the way to a practical application of germanene. Abstract : A flexible, controllable, and robust photoelectrochemical (PEC)‐type photodetector based on hydrogen‐terminated germanene is demonstrated that exhibits a high photocurrent density of 2.9 µA cm −2 with zero bias potential, excellent responsivity as well as short response time. This efficient strategy suggests a path to promising high‐performance, self‐powered, flexible photodetectors, and it also paves the way to a practical application of germanene.