[Ca24Al28O64](4+)(4e(-))　(C12A7:e(-))　has　excellent　potential　in　electric　propulsion　owing　to　various　advantages,　including　low　work　function,　low　working　temperature,　and　stable　chemical　properties.　However,　increasing　electron　concentration　enhances　the　thermionic　emission　property　of　C12A7:e(-).　This　study　used　a　chemical　method-spark　plasma　sintering　to　synthesize　Zr-doped　C12A7:e(-)　(C12(A(1　-)　(x)Z(x))7:e(-),　where　x　=　0　to　0.14).　The　study　results　show　that　C12(Al0.86Zr0.14)7:e(-)　maximum　injected　electron　concentration　(n),　conductivity　(sigma),　electron　mobility　(mu(n)),　and　zero-field　emission　current　density　(J(o))　improved　to　2.4　x　10(21)　/cm(3),　1507　S/cm,　5.2　cm(2)/V　center　dot　s,　and　2.4　A/cm(2),　respectively.　The　emission　current　density　of　the　C12(Al0.86Zr0.14)7:e(-)　could　be　maintained　at　about　2.9　A/cm(2)　under　1100　degrees　C,　4000　V,　and　600　min.　Theoretical　calculation　results　prove　that　Zr　doping　broadens　the　cage　conduction　band　(CCB)　of　C12A7:e(-)　and　reduces　the　bandgap　between　the　CCB　and　the　frame　conduction　band.　In　addition,　Zr　doping　increases　the　electronic　density　of　states　near　the　Fermi　level,　and　the　density　of　states　presents　a　continuous　state.　This　helps　to　increase　the　injected　electron　concentration　and　enhance　the　electrical　transport　and　thermionic　emission　characteristics　of　the　sample.　The　calculation　results　provide　theoretical　support　for　the　experiment.