Until now, scientists couldn't create such clean hydrogen without intensive, high-energy processes that weren't any greener than using conventional petroleum to power vehicles.
But scientists from the University of Tennessee, Knoxville, and Oak Ridge National Laboratory found that the inner machinery of photosynthesis can be isolated from certain types of algae. When coupled with a platinum catalyst, the machinery can produce "a steady supply" of hydrogen when exposed to light.
Look far back enough and it's easy to see that photosynthesis is how we indirectly get most of our energy. Fossil fuels were once energy-rich organic plant matter, which as plants used photosynthesis to generate energy. Biomass fuels that harvest plants to convert hydrocarbons into ethanol or biodiesel are one attempt to speed up the process, but the new algae-based process skips over the time- and energy-heavy plant matter part of the equation entirely.
"Our process is more direct and has the potential to create a much larger quantity of fuel using much less energy, which has a wide range of benefits," said project lead and UT Knoxville biochemistry professor Barry Bruce, in a statement.
The important aspect of the process is that the process works at scale. By using a thermophilic blue-green algae, which favors warmer temperatures, the researchers could sustain the reaction at temperatures as high as 55 degrees Celsius, or about 131 degrees Fahrenheit.
That's the temperature at which the process would be most productive -- 10 times as much, according to the research team.
Without greenhouse gas production, hydrogen could be the cleanest fuel alternative to petroleum.
The findings were published in a recent issue of the journal Nature Nanotechnology.