It appears to have been written shortly before the apostle's death (1:14). This epistle contains eleven references to the Old Testament. It also contains (3:15, 16) a remarkable reference to Paul's epistles. Some think this reference is to 1 Thess. 4:13-5:11.
Some have questioned whether Peter was the author, because the linguistic style is simpler than the First Epistle of Peter. Many scholars believe this is because Peter had assistance in writing the first epistle, and therefore the second epistle is actually Peter's own unaided writing.
This doesn't go with the 2nd epistle of Peter:
In the late 19th century, among other documents, a parchment fragment, called the "Gospel of Peter," was discovered in a Christian tomb at Akhmim in Upper Egypt. Origen (died A.D. 254), Eusebius (died 340), and Jerome (died 420) refer to such a work, and hence it has been concluded that it was probably written about the middle of the second century. It professes to give a history of Jesus' resurrection and ascension. While differing in not a few particulars from the canonical Gospels, the writer shows plainly that he was acquinted both with the synoptics and with the Gospel of John. Though apocryphal, it is of considerable value as showing that the main facts of the history of Jesus were then widely known.