Well, good morning- and welcome to the forum! When you get a minte, stop by the intro thread and say hello.
Assuming your pistol is in 9mm Parabellum (aka 9x19, 9mm Luger, etc)- you have your choice of a number of rounds made for self defense- And advertising hype from the makers aside- they all work pretty well.
Personal choice- I would avoid the 115 gr 9mm- there is too much data on poor penetration- and go for a heavier bullet. The Barnes copper 115 is an exception to that. Some of the candidates may include:
Barnes XPB 115gr HP (35515) such as loaded by Cor-Bon (DPX09115)
Winchester Partition Gold 124gr JHP (RA91P)
Winchester Ranger-T 124 gr +P JHP (RA9124TP)
Winchester Ranger Bonded 124 gr +P JHP (RA9BA)
Winchester Ranger-T 127gr JHP +P+ (RA9TA)
Winchester Ranger-T 147gr JHP (RA9T)
Winchester Bonded 147gr JHP (RA9B/Q4364)
Speer Gold Dor 124gr JHP
Speer Gold Dot 124gr JHP +P (53617)
Speer Gold Dot 147gr JHP (53619)
Remington Golden Saber 124 gr +P JHP bonded (GSB9MMD)
Remington Golden Saber 147gr JHP (GS9MMC)
Federal Tactical 124gr JHP (LE9T1)
Federal Tactical 135gr JHP +P (LE9T5)
Federal HST 147gr JHP (P9HST2)
Federal HST 124gr JHP +P (P9HST3)
HOWEVER, for an auto pistol, the ONE factor that gets overlooked too often- does it cycle in YOUR pistol 100.0000% of the time? A round that will drop a water buffalo does you no good if it will not feed in your pistol.
What we have here is... failure- to communicate.