【28th.Nov.】Efficient Artificial Photosynthesis Based on Earth Abundant Materials
日期：2017-11-28
閱讀：1504
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題目：Efficient Artificial Photosynthesis Based on Earth Abundant Materials
報告人：韓李豪 博士，美國加州理工學院研究員
時間：11月28日 (周二), 上午10:00
地點： 化學樓A518
邀請人：李新昊 特別研究員, 陳接勝 教授
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韓李豪博士簡介：
教育背景：
2004-2008： 北京郵電大學，學士
2008-2011：清華大學，碩士
2011-2015：荷蘭代爾夫特理工大學，博士
2013-2014：美國加州理工學院，聯(lián)合培養(yǎng)博士
科研經(jīng)歷：
2015-2016：瑞士洛桑聯(lián)邦理工學院，博士后
2016：日本東京大學，客座研究員
2016-今：美國加州理工學院，研究員
研究方向：
新型高效太陽能水分解器件，硅基納米晶太陽能材料，溫室氣體電解還原，太陽能污水處理等。
清華大學一等獎學金獲得者，國家優(yōu)秀留學生獎學金獲得者。擔任《Energy & Environ. Sci.》等二十多份國際刊物的特約審稿人，被《Solar Energy Materials and Solar Cells》、《Solar Energy》等期刊評為年度十大優(yōu)秀審稿人之一，《Jacobs Journal of Hydrology》期刊編輯。
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Efficient Artificial Photosynthesis Based on Earth Abundant Materials
The world-wide total installed photovoltaic (PV) power is growing so fast that within the end of this decade the electricity generated by solar energy is in the same order as hydro- and nuclear electricity. In combination with the seasonable fluctuations of solar power, this poses enormous technological challenges on the electricity grid and its storage capacity. Finding a cheap technology to store solar energy becomes, much faster than everybody is realizing, the crucial issue for a further successful introduction of solar energy technologies in to our energy infrastructure. In this contribution, we look at the conventional silicon based PV technologies and their opportunities in solar fuel technologies.
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Current state-of-the-art system components, like silicon PV modules and electrolyzers, can achieve a solar-to-hydrogen (STH) conversion efficiency of 15%. Alternative approaches, based on photoelectrochemical/photovoltaic (PEC/PV) water splitting, have demonstrated higher STH efficiencies of 15 up to 18% based on III-V semiconductor materials and Platinum electrodes. The problems of these approaches are that they are not cost-effective, the materials are not abundantly available and not resistant against aqueous environment. I present the important role of silicon processing devices and processing technology to tackle these problems.
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I demonstrate promising results on silicon based water splitting PEC/PV devices. The light excited charge carriers in photoelectrodes and electrolytes induce oxidation (photoanode) and redox reduction reactions (photocathode) at the electrode /electrolyte interfaces. The over-potential of the photoelectrodes are suppressed by the supplied voltage of the PV devices integrated in to the water splitting device. The cost effective, abundantly available and water resistant silicon can be integrated in both the PEC and PV part of the devices.
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I also discuss technical feasibilities and barriers of solar-driven water-splitting systems based on particle slurry reactors with mediators. A particle suspension based reactor using titanium dioxide (TiO2) particles and mediators in aquatic electrolyte is chosen. The realization of reduction of water to hydrogen by oxidizing the bromide ions (Br-) into bromide (Br2), and the oxidation of water to oxygen by reducing the Fe3+ into Fe2+ ions is presented. As a result, the illuminated water is effectively split into hydrogen (H2) and oxygen (O2) in different baggies without the requirement of further separation.
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