Raman Spectroscopy, Photocatalytic Degradation, and Stabilization of Atomically Thin Chromium Tri-iodide

• DOI: 10.1021/acs.nanolett.8b01131
• Publication Date: 2018-06-04T16:25:37Z
• Authors: Dmitry Shcherbakov; Petr Stepanov; Daniel Weber; Yaxian Wang; Jin Hu; Yanglin Zhu; Kenji Watanabe; Takashi Taniguchi; Zhiqiang Mao; Wolfgang Windl; Joshua Goldberger; Marc Bockrath; Chun Ning Lau
• Keywords: Degradation; Magnetic semiconductor

As a 2D ferromagnetic semiconductor with magnetic ordering, atomically thin chromium tri-iodide is the latest addition to family of two-dimensional (2D) materials. However, realistic exploration CrI3-based devices and heterostructures challenging due its extreme instability under ambient conditions. Here, we present Raman characterization CrI3 demonstrate that main degradation pathway photocatalytic substitution iodine by water. While simple encapsulation Al2O3, PMMA, hexagonal BN (hBN) only leads modest reduction in rate, minimizing light exposure markedly improves stability, sheets sandwiched between hBN layers are air-stable for >10 days. By monitoring transfer characteristics CrI3/graphene heterostructure over course degradation, show aquachromium solution hole-dopes graphene.