While you can connect it to the phone using the right cord/adapter, you probably will not be able to get it to work the way you are trying to.
The reason being that the external storage you are looking to us would (most likely) not get enough power from the phone to actually make it work. Were you to actually find a way to increase the power, then "maybe" you could get it to work. But, this would be awkward at best. A set up holding those two, if not a third item for a power source, would be quite complicated to carry. To say the least.
You would be better served either buying an actual video recorder, or perhaps stocking up on large capacity SD cards. Which then can be transferred over to a computer (and your HDD) for storage and...