[jacobian]

No, there aren't. Knives dull over time; even the most durable steel formulations need sharpening eventually. Those ceramic knives are pretty robust, but they too will dull. More importantly, they're extremely brittle; my experience with them is that they chip very quickly and are really unsuitable for anything other than very light use. For your use, they might be ok, but I think you'd end up being annoyed when they break sooner than you want.

I recommend something from the Victorinox Fibrox line to folks like you who just want to cut stuff and not think about knifes. They're very sharp out of the box, quite durable, and will last a long long time before going dull. When they do, they're so cheap (like $25) that you could just get a new one rather than messing around with sharpening.

[TheSpiceIsLife]

Those $6 tools with the three grades of sharpening V’s work well enough to make a $25 knife last fairly indefinitely in this particular use case.

[eeperson]

Although beware, those pull through sharpeners are notorious for doing a terrible job sharpening knives. They take off far more material than needed and tend to produce an edge that isn't very sharp. YMMV.