Carbene‐Functionalized Single‐Walled Carbon Nanotubes and Their Electrical Properties

Abstract Pure metallic single‐walled carbon nanotubes (m‐SWCNTs) are very desirable for many electrode and interconnecting applications. However, the lack of reliable processing techniques to sort m‐SWCNTs from the as‐synthesized SWCNT samples is an obstacle to these applications. The effects of carbene‐based covalent functionalization on the electrical properties of an isolated m‐SWCNT, a semiconducting (s)‐SWCNT, and a mixture network of both m‐ and s‐SWCNTs are reported. For the first time, a semiconducting‐to‐metallic SWCNT transition upon dichlorocarbene functionalization is observed. Interestingly, the transition is reversible upon thermal annealing under ambient conditions. The electrical properties of m‐SWCNTs remain largely unaffected whereas the on‐state conductivity of s‐SWCNTs is greatly reduced by this process, in agreement with the relevant theoretical predictions. These findings could pave the way for fabricating large‐scale SWCNT‐based interconnects and electrodes in full‐carbon integrated circuits.