Premium
Quasi‐Monolayer Black Phosphorus with High Mobility and Air Stability
Author(s) -
Tan Sherman Jun Rong,
Abdelwahab Ibrahim,
Chu Leiqiang,
Poh Sock Mui,
Liu Yanpeng,
Lu Jiong,
Chen Wei,
Loh Kian Ping
Publication year - 2018
Publication title -
advanced materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.707
H-Index - 527
eISSN - 1521-4095
pISSN - 0935-9648
DOI - 10.1002/adma.201704619
Subject(s) - monolayer , materials science , intercalation (chemistry) , alkali metal , raman spectroscopy , band gap , electron mobility , metal , photoluminescence , direct and indirect band gaps , inorganic chemistry , black phosphorus , chemical physics , nanotechnology , optoelectronics , chemistry , organic chemistry , metallurgy , physics , optics
Black phosphorus (BP) exhibits thickness‐dependent band gap and high electronic mobility. The chemical intercalation of BP with alkali metal has attracted attention recently due to the generation of universal superconductivity regardless of the type of alkali metals. However, both ultrathin BP, as well as alkali metal‐intercalated BP, are highly unstable and corrode rapidly under ambient conditions. This study demonstrates that alkali metal hydride intercalation decouples monolayer to few layers BP from the bulk BP, allowing an optical gap of ≈1.7 eV and an electronic gap of 1.98 eV to be measured by photoluminescence and electron energy loss spectroscopy at the intercalated regions. Raman and transport measurements confirm that chemically intercalated BP exhibits enhanced stability, while maintaining a high hole mobility of up to ≈800 cm 2 V −1 s −1 and on/off ratio exceeding 10 3 . The use of alkali metal hydrides as intercalants should be applicable to a wide range of layered 2D materials and pave the way for generating highly stable, quasi‐monolayer 2D materials.