Most phd nursing programs
do not respect an education focus. An EdD may be more appropriate. I personally believe it is a great specialization. A phd is a research degree. No research grants or government funding will be awarded to a research focus on education.
They prefer something that improves patient outcomes or safety. They want to benefit patients outcomes, not nursing outcomes. Since phd program faculty want funding and publication, they will not "waste" time on research topics that have neither. Depending on what you want to teach a DNP may even be more appropriate. I know of no phd nursing programs with an education focus ( a few will focus on pt education)
Also, stay away from Phoenix or the other online programs similar to it. That is if you want to work in academia. They will not accept a degree from these programs. A safe rule is that if the ability to pay tuition is the hardest enrollment requirement, don't attend. No reputable program for a phd will accept a C average, no entrance exam, and no proof of scholarly aptitude. Not to mention their tuition is too high, find a good public university with an instate rate. You will finish with a fourth or half of the cost.