Dehydrogenation kinetics of 2LiBH4Â +Â MgH2 enhanced by hydrogen back pressure and a CuCl2 catalyst

► The kinetics of MgB2 formation is remarkably enhanced by the H2 back pressure. ► A nucleation-growth process for the MgB2 formation. ► CuCl2 can catalyze the dehydrogenation of 2LiBH4 + MgH2.