区别如下:
instead是副词,意为代替顶替、反而、却
instead of是复合介词后面可接名词和代词以外的词,如形容词,副词,动词和介词,意为代替作为…的替换。 
例句:
Now I can walk to work instead of going by car.
现在我可以步行去上班,而不必开车了。
I'll tell you what ─ let's stay in instead.
听我说,咱们还是待在家里吧。
Now I can walk to work instead of going by car.
现在我可以步行去上班,而不必开车了。
The authorities used quiet persuasion instead of the big stick.
当权者平心静气地劝说,而不是施加压力