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I am a student doing a little research into alternative power sources, and came across your article on storing the sun's energy (Sunlight in a Bottle).  I am not a chemistry major, and was wondering if there were any ways that you knew of to use actual sunlight to separate water molecules.  What could be some other ways of separating water besides electrolysis?  

I am not familiar with any other means of splitting water (although that doesn't mean that there are any).  The bonds that hold water molecules together (one water molecule attached to another) are called hydrogen bonds.  These bonds are fairly weak which explains why moderate amounts of heat can cause them to break and allow water molecules to separate from one another and become a vapor.  But, the actual molecules are held together by very stong polar bonds that, to my knowledge, require electricity to break.  While not much electricity is needed (as low as 6 volts), I do believe that electricity is necessary.  I also do now know of any way that sunlight can be used to directly dissolve these polar bonds in water.   Although these probably aren't the results that you wanted to hear, I hope I was successful in explaining why.