One of the problems of brute force electrolysis has always been the amount of energy it takes to split water into hydrogen and oxygen. The use of different kinds of metal or chemical catalysts, sound wave frequencies and other methods to loosen the bonds between hydrogen and oxygen atoms have met with encouraging success.
And, another attempt at lowering the voltage requirements of splitting water has gained laboratory success by Japanese researchers. The Solar Light Energy Conversion Group, the Energy Technology Research Institute and the National Institute of Advanced Industrial Science and Technology have developed a tungsten oxide (WO3) photocatalyst that along with solar energy reduces the voltage requirements for producing hydrogen by 50-percent.
According to the press release, “The high efficiency of the WO3 photocatalyst was achieved using a new method—treatment of the surface of the photocatalyst with Cesium (Cs). The activity of the treated catalyst is more than ten times that of untreated catalysts. The quantum yield of the new photocatalyst is 19% under visible light of wavelength 420 nm and is approximately 50 times the previously reported values (0.4%)*. The use of solar energy can reduce the voltage required for water electrolysis by almost 50%. Hence, the low-cost production of hydrogen is expected.”
One of the main arguments that critics have of producing hydrogen (even from renewable methods such as solar) is that it takes too much energy to produce H2 and why not just store this energy in batteries. By significantly lowering the voltage needed to produce hydrogen fuel from water, this argument is taken away.
Hydrogen cars have a longer range and much quicker refueling times than battery electric vehicles and if the production of hydrogen is cost effective this means that one more hurdle will be crossed in the realization of a hydrogen-based transportation system.