The title is misleading.
Now, as someone who has worked with hydrogen under pressure, using this technology in the third world will be interesting, to say the least (chase down a MSDS on Hydrogen). Fuel cells might be a different matter.
Actually ALL leaves produce hydrogen as the first chemical step in carboHYDRATE production. The hydrogen never escapes the chloroplast though it is used to reduce CO2 to sugars but make no mistake every photosynthetic organism on earth starts with using solar photons to break H2O in to H+ OH. There are a number or bacteria that can directly use H+ or H2 to synthesis a number or organic molecules on a industrial scale CH4 from Methogenic bacteria can be feed CO2 and H2 and Methane is the end product. Other Ecoli can take H2 or H+ and CO2 turn it into butanol or glucose or ethanol or acetic acid. Plants are only 1% efficient at converting sun light into biomass these cells should be like most single band gap cells about 10% eff. Forget biofuels make food with these things for monogastric animal feeds. A ten fold improvement in biomass rates would revolutionize the feed and food industries. Look up the electrofuels DOE program they have at least 8 organisms that can take free hydrogen and turn it into some kind of carbohydrate. That is well the essence of what a leaf is water + sun = carbohydrates. If they can get the costs per meter squared down enough to produce sugars at 15 cents per lb they will undercut any biological production of biomass on the planet. Given that they are starting out already 10 to 15 times more efficiency in solar photons to free hydrogen and Ecoli are upwards of 90% efficient at converting that into cellular mass they have a HUGE head start on nature.