Only the first sentence is correct. It means that the artist is well known for often using purple in his art. The second sentence is grammatically incorrect. If you wanted to use the gerund you could change the second sentence to this "The artist is famous for frequently using purple". In the art world the first sentence would be said before someone says the second sentence because the first one sounds more native. It is sort of an idiomatic phrase someone could also say "You use of pepper in this meal was a good idea" meaning that the speaker appreciates the pepper in the dish. If you were to use that phrase it is always followed by 'of' Hope this helps! Keep learning :-)