What is a better input for Word2Vec?
The answer to this question is that it depends. The primary approach is to pass in the tokenized sentences (so SentenceCorpus in your example), but depending on what your goal is and what the corpus is you're looking at, you might want to instead use the entire article to learn the embeddings. This is something you might not know ahead of time -- so you'll have to think about how you want to evaluate the quality of the embeddings, and do some experiments to see which 'kind' of embeddings are more useful for your task(s).