It's difficult to have people who don't know you personally give you advice. If she isn't interested in her own, pushing it on her won't help. Spending time with black friends will help, or if you don't have any, you should try making friends with a few nice black guys. Don't just put out an ad on Craig's list and decide to have her meet "an old friend" for lunch thinking he will charm the pants off her.
You have an advantage over me in regards to your Chinese wife, you can just talk to her about it. My wife and I still have translation issues just talking, much less trying to talk to her about your fantasies for her. You speak Chinese, use words to talk to her.