Unveiling the degradation process of monolayer WSe2 with aging

This is the authors' abstract. We don't add key points for this paper.

We present an effective protocol for extracting localization energy from WSe2 monolayers, based on temperature-dependent spectral variation of photoluminescence (PL), and observe time-sequential changes over a long period of time. We found that even freshly exfoliated WSe2 exhibits deviation from the Varshni formula upon exposure to air, while the temperature-dependent PL lineshapes of h-BN encapsulated WSe2 match well with delocalized features for as long as two years of the aging period. Our findings support the prospect of h-BN encapsulation for monoatomic transition metal dichalcogenides to meet the longevity condition, which is a prerequisite for practical components in the electronics industry.