Is there an ensemble technique package for unsupervised learning in R?

I am trying to implement unsupervised learning algorithms on an unlabeled data set in R. I have used the algorithms like PCA and KNN, I want to see if I can further improve my results using ensemble methods. I am trying to search for a package that is already built for this purpose.

An example for a package for supervised learning is Adaboost for classification. I am looking for an equivalent for unsupervised learning. Please suggest packages you know or you have used.