In terms of chemically bonding hydrogen to something else for easier storage and transport, I think the best plan is to add carbon so it becomes convenient synthetic methane or gasoline that we can use in our existing distribution infrastructure and machinery.

...of course, that just goes to show how absurd the entire concept of hydrogen is, considering that it's almost exclusively made from those things in the first place!

If we really want a sustainable portable energy storage medium that isn't electricity, my vote would be for cracking water into hydrogen with electrolysis and then immediately (in the same facility) converting that + CO2 to synthetic hydrocarbon fuel using the Fischer-Tropsch process.