Ever since the Hindenburg, hydrogen has not been seen as a viable energy source simply because it is so flammable. However, there is a breakthrough in the science that could allow for hydrogen-based fuels to be useful and safe.
The artificial leaf that the scientists at Arizona State University have developed is designed to essential replicate the process of photosynthesis within water to separate oxygen and hydrogen from water molecules. Essentially, the molecules are converted into oxygen that evaporates and free hydrogen that can be used in the fuel production process.
This is the first step in having energy efficient hydrogen used as a fuel. Plus, it could get right of greenhouse gas emissions because hydrogen burning does not produce greenhouse gases of any kind. Cleaner burning fuel could be in the future if this artificial leaf could be used to separate water effectively in the lab.