Silicon Photoanodes for Solar-Driven Oxidation of Brine: A Nanoscale, Photo-Active Analog of the Dimensionally-Stable Anode
Silicon Photoanodes for Solar-Driven Oxidation of Brine: A Nanoscale, Photo-Active Analog of the Dimensionally-Stable Anode
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DOI：
10.1149/2.0791816jes
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发表时间：
2018-12
影响因子：
3.9
通讯作者：
Robert Tang-Kong;C. O’Rourke;A. Mills;P. McIntyre
中科院分区：
文献类型：
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作者：
Robert Tang-Kong;C. O’Rourke;A. Mills;P. McIntyre
11我们报告了第一个结果，ALD-TiO 2层将硅电子耦合到覆盖的催化剂涂层上，同时抑制盐水分解过程中的腐蚀，盐水分解反应不仅能够产生燃料（H 2），而且还能够产生消毒剂（Cl 2或NaOCl）。n型硅光阳极14和p+-硅阳极由1.7nm的无定形TiO 2涂层和2nm的Ir涂层保护。p+-Si/TiO 2 /Ir阳极能够实现氯化物的氧化（0.5 M H2SO 4，3.5 M NaCl）在16黑暗与低过电位相比，水的氧化（0.5 M H2SO 4）。尽管标准氧化还原电位的差异为130 mV，但仍存在0.294 V 17的过电位差。在1个太阳照射下，光电压约为。0.566 V通过比较被照射的n-Si/TiO 2 /Ir光电阳极与暗p+-硅阳极来实现。虽然n- 20 Si/TiO 2 /Ir光阳极只是光合作用盐水21分解所需的最终串联电池的一半，但其氯化物氧化的ABPE为1.42%，约为1.42%。是水氧化的28倍。在6天的23计时电位测试中，n-Si/TiO 2 /Ir光阳极在1 mA cm-2下保持稳定。
11 We report the first results in which ALD-TiO 2 layers electronically couple silicon to an overlying 12 catalyst coating while inhibiting corrosion during brine splitting, a reaction that is capable of 13 generating not only a fuel (H 2 ) but also a disinfectant (Cl 2 or NaOCl). An n-type silicon photoanode, 14 and a p+-silicon anode are protected by a 1.7 nm coating of amorphous TiO 2 and 2 nm coating of Ir. 15 The p+-Si/TiO 2 /Ir anode is able to effect the oxidation of chloride (0.5 M H 2 SO 4 , 3.5 M NaCl) in the 16 dark with a low overpotential compared to that for oxidation of water (0.5 M H 2 SO 4 ). The 0.294 V 17 overpotential difference occurs despite the difference in standard redox potentials, E = (E o (Cl 2 /Cl - ) - 18 E o (O 2 /H 2 O)), is 130 mV. Under 1 sun irradiation a photovoltage of ca. 0.566 V is achieved by 19 comparing the illuminated n-Si/TiO 2 /Ir photoanode with the dark p+-silicon anode. Although the n- 20 Si/TiO 2 /Ir photoanode is only one half of an eventual tandem cell needed for photosynthetic brine 21 splitting, its ABPE for chloride oxidation is 1.42%, ca. 28 times that for water oxidation. The 22 illuminated n-Si/TiO 2 /Ir photoanode remained stable at 1 mA cm -2 during a six-day 23 chronopotentiometry test.