Can the S2 charger be plugged into my I-phone wall charger?

Insten USB 2A Black AC Wall Charger Adapter For iPad Pro Mini 4 3 2 Air...

have you tried using a different charger? Try plugging it into the USB slot of a computer, does it charge then?

try to clean the terminal points.
if not used.
replace it with brand new terminals or good ones.

Usually this lack of charging is a faulty mini usb connector inside the SII phone or maybe the mini USB plug on the end of charger cable. If you have a friend with a working SII use their phone to verify your battery or try their good battery in your phone. This will confirm it' s a charging / battery issue.
Not sure if you did this:A workaround for a faulty mini USB conn. in the SII would to be to buy a new battery and an external battery charger with battery holder stand. Charge batteries in the stand and change the charged batteries over into the Galaxy SII as needed.

Either your battery needs to be replaced or charging port is damaged

check plug usb try to cleaning first

Try connecting your S2 with the usb cable provided to your desktop/laptop. If it starts recharging, then it is definitely your charger thats done for. Get a new charger...

Try a car charger. If the car charger works, then it is either
A) Your power outlet
B) Your wall charger Power Supply unit
C) The phone connector on your wall charger.

If it doesn't work on the car charger, then it is most likely your phone charging system or the connection for charging on your phone. Either way, you will most likely need a new phone. Sorry.

your old battry boost for 6v charge 1 second try it now working or new samsung orginal battry use only other not working

Close the flip screen. Unplug charger from the wall and the phone. First plug in phone jack into phone BUT make sure to push it in a bit sideways. Not too much it can break the pins but just with a little angle. When you hear good click than plug charger unit in the wall.