Ge Jianbang, Zou Xingli, Almassi Soroush, Ji Li, Chaplin Brian P, Bard Allen J
Center for Electrochemistry, Department of Chemistry, The University of Texas at Austin, Austin, TX, 78712, USA.
Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA.
Angew Chem Int Ed Engl. 2019 Nov 4;58(45):16223-16228. doi: 10.1002/anie.201905991. Epub 2019 Sep 26.
The current Si production process is based on the high-temperature (1700 °C) reduction of SiO with carbon that produces large amounts of CO . We report an alternative low-temperature (850 °C) process based on the reduction of SiO in molten CaCl that does not produce CO . It utilizes an anode material (Ti O ) capable of sustained oxygen evolution. Two types of this anode material, dense Ti O and porous Ti O , were tested. The dense anode showed a better performance. The anode stability is attributed to the formation of a protective TiO layer on its surface. In situ periodic current reversal and ex situ H reduction could be used for extending the lifetime of the anodes. The findings show that this material can be applied as a recyclable anode in molten CaCl . Si wires, films, and particles were deposited with this anode under different cathodic current densities. The prepared Si film exhibited ≈30-40 % of the photocurrent response of a commercial p-type Si wafer, indicating potential use in photovoltaic cells.
当前的硅生产工艺是基于在高温(1700°C)下用碳还原SiO,该过程会产生大量的CO。我们报道了一种基于在熔融CaCl中还原SiO的替代低温(850°C)工艺,该工艺不产生CO。它使用了一种能够持续析氧的阳极材料(TiO)。测试了这种阳极材料的两种类型,致密的TiO和多孔的TiO。致密阳极表现出更好的性能。阳极稳定性归因于其表面形成了一层保护性的TiO层。原位周期性电流反向和异位H还原可用于延长阳极寿命。研究结果表明,这种材料可作为熔融CaCl中的可回收阳极。使用该阳极在不同的阴极电流密度下沉积了硅线、薄膜和颗粒。制备的硅薄膜表现出约为商用p型硅片光电流响应的30 - 40%,表明其在光伏电池中的潜在应用价值。