In essence, what
@spikeymike said, not all chargers are interchangeable, not all cables are interchangeable.
In the case of the model number provided, conflicting info imo. Samsung has several versions of this charger, all seem to advertise USB Power Delivery, but also mention Samsung's Adaptive Fast Charging which is not USB PD. So not a big surprise that this charger is not communicating correctly with the Lightning connector and or phone (there is a chip in Lightning cables that do a fair share of the communication between widgets).
www.bytecable.com
Posted: December 5, 2012
www.techinsights.com
So as suggested, and seems like you will be doing, get an Apple charger. Or an Anker, as they seem to be pretty agnostic with regards to quick charging (they've been rock solid for me with Apple devices).