I would like to perform PCA on my data set (n=179). My result currently ends up with only one factor. I do not really know how to proceed further since I wanted to do Cluster analysis afterwards but I think with only one factor it is not possible.
First, if you have only 9 variables, you can do cluster analysis on the original variables and not do PCA at all. Why are you doing PCA?
Second, it is possible to do cluster analysis on one variable. See, for instance, this thread
PCA works best if you have a lot of data. In particular if some variables aren't continuous or you have many duplicate samples. As a rule of thumb, I have seen the recommendation of at least 3p² samples. So for p=9, that rule would suggest you need many more samples to get a reliable estimate from PCA. Unfortunately, I can't find any source for that rule of thumb.
Because of this, I would suggest to not use PCA here for analysis. Because I don't see why you need it, and it just adds to your problems. You can definitely cluster multiple variables. But you can still try PCA for visualization only.