Loget G, Mériadec C, Dorcet V, Fabre B, Vacher A, Fryars S, Ababou-Girard S
Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR6226-ScanMAT-UMS2001, F-35000, Rennes, France.
Univ Rennes, CNRS, IPR (Institut de Physique de Rennes)-UMR 6251, F-35000, Rennes, France.
Nat Commun. 2019 Aug 6;10(1):3522. doi: 10.1038/s41467-019-11432-1.
Apart from being key structures of modern microelectronics, metal-insulator-semiconductor (MIS) junctions are highly promising electrodes for artificial leaves, i.e. photoelectrochemical cells that can convert sunlight into energy-rich fuels. Here, we demonstrate that homogeneous Si/SiO/Ni MIS junctions, employed as photoanodes, can be functionalized with a redox-active species and simultaneously converted into high-photovoltage inhomogeneous MIS junctions by electrochemical dissolution. We also report on the considerable enhancement of performance towards urea oxidation, induced by this process. Finally, we demonstrate that both phenomena can be employed synergistically to design highly-efficient Si-based photoanodes. These findings open doors for the manufacturing of artificial leaves that can generate H under solar illumination using contaminated water.
金属-绝缘体-半导体（MIS）结不仅是现代微电子学的关键结构，也是用于人造叶片（即能够将阳光转化为富含能量的燃料的光电化学电池）的极具前景的电极。在此，我们证明，用作光阳极的均匀Si/SiO/Ni MIS结可以用氧化还原活性物质进行功能化，并通过电化学溶解同时转化为高光电电压的非均匀MIS结。我们还报告了这一过程引起的尿素氧化性能的显著增强。最后，我们证明这两种现象可以协同用于设计高效的硅基光阳极。这些发现为制造能够在太阳能照射下利用污水产生氢气的人造叶片打开了大门。
