{"id":9942,"date":"2015-05-21T20:28:41","date_gmt":"2015-05-22T03:28:41","guid":{"rendered":"http:\/\/cafe.foundation\/blog\/?p=9942"},"modified":"2015-05-21T20:28:41","modified_gmt":"2015-05-22T03:28:41","slug":"hzb-makes-h2-fools-gold","status":"publish","type":"post","link":"http:\/\/cafe.foundation\/blog\/hzb-makes-h2-fools-gold\/","title":{"rendered":"HZB Makes H2 With Fool’s Gold"},"content":{"rendered":"

Hydrogen, two atoms of which are in every molecule of water, is wildly abundant, but elusive to extract for our transportation needs.\u00a0 Common means of pulling the H2 from the H2O used fossil fuels, and thus negate the good intentions for its use.\u00a0 Several people have tried cleaner means of \u201csplitting water,\u201d including Daniel Nocera of MIT and Harvard, and researchers around the world, including those in the Netherlands and Germany.\u00a0 One notable recent accomplishment at the HZB (Helmholtz Zentrum Berlin) Institute for Solar Fuels<\/a> involves a new composite photocathode that generates H2 \u201cwith high quantum efficiency\u201d using sunlight.<\/p>\n

The Institute says, \u201cThe photocathode consists of a thin film of chalcopyrite produced by HZB\/PVcomB coated with a newly developed thin film of photo-resistant titanium dioxide (TiO2) containing platinum nanoparticles.\u201d<\/p>\n

\"Layering<\/a>

Layering of HZB artificial photosynthesis photocathode<\/p><\/div>\n

Of course your editor, who wishes he had taken better notes in chemistry class, Googled the unfamiliar term.\u00a0 A University of Michigan note on CuFeS2\u00a0\u2013 Copper Iron Sulfide explains, \u201cChalcopyrite was the mineral upon which Bronze Age civilizations were built. Within the last century, it also became the mineral foundation for our modern electrical age. Our primary source of copper, chalcopyrite\u2019s name comes from the Greek words \u2018chalkos\u2019 and \u2018pyrites\u2019, which respectively mean \u2018copper\u2019 and \u2018striking fire\u2019. With its metallic luster and bright golden color, chalcopyrite can fool people into thinking it is gold. It is one of two minerals, the other being pyrite, that are commonly known as \u2018fool\u2019s gold\u2019\u201d.<\/p>\n

With its pricey components, the layer covering the chalcopyrite film protects it from corrosion and acts as a catalyst, speeding formation of hydrogen and acting as a photodiode showing \u201cphotoelectric current density and voltage comparable to those of a chalcopyrite-based thin film solar cell.\u201d<\/p>\n

Electrodes used in splitting water, such as platinum or platinum-iridium alloys, are usually from the pricier side of the periodic table.\u00a0 Despite the platinum nanoparticles in the coating over the chalcopyrite, the \u201cfool\u2019s gold\u201d photocathode helps keep the price of these devices in a moderate range.<\/p>\n