太阳能电解水成氢与氧

太阳能电池板一般只能将阳光转化为电能或是热能，但是进行光合作用的植物却能把阳光变成化学能。如今麻省理工的科学家Daniel Nocera希望能把光合作用带入寻常人家。显然，太阳能只有在出太阳的时候才能使用。Nocera的想法是把获得的太阳能用于电解，即把水分子分解成氢气和氧气。这两种气体随后可以在需要的时候，通过燃料电池再次合成水。其难点在于现在的电解技术需要耗费大量的能量，还得在高温高压的碱性环境中进行。但让人惊讶的是，其中的原因是氧气很难从水中分离出来，而不是氢气。

Solar panels typically convert sunlight into electricity or heat. But photosynthetic vegetation converts sunlight into chemical energy. Now M.I.T.’s Daniel Nocera wants to bring photosynthesis to your home. Solar power only works, obviously, when the sun shines. Nocera’s idea is to take solar power and use it to for electrolysis—to break apart water into hydrogen and oxygen—which then could be recombined when needed in a fuel cell. The problem is that current electrolyzer technology takes a lot of energy in a harsh, alkaline environment. That’s because, surprisingly enough, it’s hard to get the oxygen out of the water, not the hydrogen.

Nocera为氧气分离步骤设计了新的催化剂，反应在常温常压下的一杯水中就能进行。当电流通过电极时，水中的磷酸盐和钴会在电极上形成一层薄膜，氧气泡泡就开始往外冒了。这项研究发表于7月31日发行的《科学》杂志上。这个系统还可以与另一个电极耦合产生氢气。Nocera相信在几年之内，电解装置会变得更高效更低廉。

Nocera designed a new catalyst for that oxygen step that works at room temperature and pressure, in a glass of water. When a current runs through an electrode, phosphate and cobalt in the water form a thin film on that electrode. And O2 bubbles right up. The work appears in the July 31st issue of the journal Science. This system could be paired with another electrode for the hydrogen side. Nocera believes that electrolyzers could be cheap and efficient within a few years.

本文由Crux译自60-Second Science，英语作者Cynthia Graber
转载星座下的神迹（http://www.cruxblog.org