Sea sponge leads way to cheaper solar cells
Marine sponges can harvest silicon from seawater and use it to build spiky filaments all over their body, inspiring the development of a cheap, low-energy method of manufacturing solar cells. The current way of making solar cells is done at high temperature and very low pressure, making it an expensive and energy-intensive process. Certain sponges, ike the orange puffball sponge Tethya aurantia, naturally synthesise pristine layers of silica without benefit of high temperatures or low pressures, and at near-neutral pH. T. aurantia does this using an enzyme called silicatein to catalyse the conversion of silicic acid in seawater into its silica spikes. Structures like this are known to make photovoltaic cells more efficient, so the researchers set about developing an analogous low-energy process that produces structured layers of zinc oxide - a widely used solar cell semiconductor.