Solar Energy Harvesting Using 1 Percent of Current Materials
Imagine a world where sunlight can be captured to produce electricity anywhere, on any surface. The makers of thin-film flexible solar cells imagine that world too. But a big problem has been the amount of silicon needed to harvest a little sunshine.想象一下这样一个世界：人类能收集阳光在所有地点、所有表面上发电，薄膜软性太阳电池的制造者也希望有这么个世界。可还有个大问题：只收集一丁点阳光都需要大量的硅。
Now, researchers [led by Harry A. Atwater] at Caltech say they’ve designed a device that gets comparable solar absorption while using just one percent of the silicon per unit area that current solar cells need. The work was published in the journal Nature Materials.
现在加利福尼亚理工学院由哈里·A·亚特华德领导的研究者们表示他们发明了一种设备，只用现有太阳能电池单位面积所需硅的百分之一就可得到数量相当的太阳能。研究发表在《自然材料》上。
The research team tried silicon wire arrays instead of traditional silicon panels. These wires have been shown to do a good job converting sunlight to usable energy on the nanoscale. But the scientists had to create wires a thousand times longer.
研究小组用硅线阵列取代传统的硅太阳能板，这些硅线在纳米层面把阳光转化为可用能源上表现良好，可科学家们还得造出长度为目前一千倍的硅线。
Light bounces around within the wires and is eventually absorbed when it hits at the correct angle. But there was a problem: too much light was leaking out. Adding nanoparticles of alumina kept much more of the light scattering until it got absorbed. The result is a system that virtually matches silicon wafer light absorption and may be more efficient at converting light to electricity, while using a tiny fraction of the material.
光线在硅线内部反射，直至达到正确角度被吸收。但还有一个问题——太多光线漏到硅线外面了。添加氧化铝纳米颗粒可使大多数光线保持散射直至被吸收，其结果就是形成一个与硅片光吸收相匹配的系统，并用极小一部分材料使光转化为电能更具效率。