Duan Chunyang, Wang Hui, Ou Xuemei, Li Fan, Zhang Xiaohong
Nano-organic Photoelectronic Laboratory and Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
ACS Appl Mater Interfaces. 2014 Jun 25;6(12):9742-50. doi: 10.1021/am5021414. Epub 2014 Jun 6.
Photoelectrochemical (PEC) water splitting to produce H2 is a renewable method for addressing the worldwide energy consumption increasing and fossil fuels storage shrinking. In order to achieve sustainable PEC H2 production, the semiconductor electrodes should have good photo-absorption ability, proper band positions, and chemical stability in aqueous condition. Different from the large-band-gap semiconductors such as TiO2, which can work efficiently under UV light, Si is an narrow-band-gap semiconductor that can efficiently absorb visible light; however, Si is indirect semiconductor and susceptible to photocorrosion in aqueous solution. In this paper, we demonstrate a new strategy of first protecting and then activating to develop a stable visible light photoanode for photoelectrochemical hydrogen production. This AgNPs/PEDOT/SiNW arrays show an encouraging solar-to-chemical energy conversion efficiency of 2.86 % and a pronounced incident photo-to-current conversion efficiency (IPCE) across the whole visible region. Our strategy proposed here contributes to further improvement of corrosion protection and solar energy harvesting for narrow-band-gap semiconductors that employed in visible light photoelectrochemical and photoelectric conversion applications.
光电化学（PEC）水分解制氢是一种可再生方法，可应对全球能源消耗不断增加和化石燃料储备不断减少的问题。为了实现可持续的PEC制氢，半导体电极应具有良好的光吸收能力、合适的能带位置以及在水性条件下的化学稳定性。与能在紫外光下高效工作的大带隙半导体（如TiO₂）不同，硅是一种窄带隙半导体，能有效吸收可见光；然而，硅是间接半导体，在水溶液中易受光腐蚀。在本文中，我们展示了一种先保护后激活的新策略，以开发用于光电化学制氢的稳定可见光光阳极。这种AgNPs/PEDOT/SiNW阵列显示出令人鼓舞的2.86%的太阳能到化学能转换效率，以及在整个可见光区域显著的入射光到电流转换效率（IPCE）。我们在此提出的策略有助于进一步改善用于可见光光电化学和光电转换应用的窄带隙半导体的腐蚀防护和太阳能收集。
