look ,

electon has higher mobility than hole because when electro moves from VALENCE BAND to CONDUCTION BAND , then it create HOLES .............( WHICH R VERY CLOSE TO NUCLEUS AND experience COULOMBIC FORCE ) , there fore holes have their mobility less than electrons.

SECONDLY , in valence band, CHARGE density is larger , therefore holes have difficulty to move ........but in CONDUCTION BAND where electrons have gone , has charge density very less.............therefore

now u have understood electrons have higher mobilty than holes

hope im right ,

please give some grades........