I don't know about bitbond, but the average apr of btcjam is 9% (with autoinvest on, not manual investing). It would take 8 years(!!!) of compounding interest to double $100,000. So... no. OP wants it done in a year.
I don't think that there is a good way to do it. If there was a safe way to double $100,000, wouldn't everybody do it?
I don't think you should discount bitcoin p2p lending so easily. This guy made 117% return within 12 months. https://www.bitbond.com/340VAQ7GMQ/investments so it is possible. Will it be easy? No, definitely not.... but it can be done.
^^ The guy was giving out loans with $400, not $100,000. It's easy to double a balance when it's small, but it's extremely unlikely that you can double $100,000 in a year. Do you see people asking for 100k usd loans on bitbond? And how many of them would pay such a high interest rate?