Sensitive electron capture decay rate of 7Be encapsulated in carbon nanotubes: A density functional study

► We study the electron capture (EC) decay rate of Be atom. ► The EC decay rate changes by encapsulating Be atom into carbon nanotubes (CNTs). ► Half-life of Be@(5,4) CNT and Be@(6,3) CNT is estimated to be 52.5 days. ► The half-life is close to the previously reported minimum (52.47 days of Be@C60). ► Hybridization effect accounts for the changes in the decay rate and half-life.