Nanostructured Ternary FeCrAl Oxide Photocathodes for Water Photoelectrolysis

详细信息    查看全文

• 作者：Ilina Kondofersky ; Alexander Müller ; Halina K. Dunn ; Alesja Ivanova ; Goran Štefanić ; Martin Ehrensperger ; Christina Scheu ; Bruce A. Parkinson ; Dina Fattakhova-Rohlfing ; Thomas Bein
• 刊名：Journal of the American Chemical Society
• 出版年：2016
• 出版时间：February 17, 2016
• 年：2016
• 卷：138
• 期：6
• 页码：1860-1867
• 全文大小：503K
• ISSN：1520-5126

文摘

A sol–gel method for the synthesis of semiconducting FeCrAl oxide photocathodes for solar-driven hydrogen production was developed and applied for the production of meso- and macroporous layers with the overall stoichiometry Fe_0.84Cr_1.0Al_0.16O₃. Using transmission electron microscopy and energy-dispersive X-ray spectroscopy, phase separation into Fe- and Cr-rich phases was observed for both morphologies. Compared to prior work and to the mesoporous layer, the macroporous FeCrAl oxide photocathode had a significantly enhanced photoelectrolysis performance, even at a very early onset potential of 1.1 V vs RHE. By optimizing the macroporous electrodes, the device reached current densities of up to 0.68 mA cm^–2 at 0.5 V vs RHE under AM 1.5 with an incident photon-to-current efficiency (IPCE) of 28% at 400 nm without the use of catalysts. Based on transient measurements, this performance increase could be attributed to an improved collection efficiency. At a potential of 0.75 V vs RHE, an electron transfer efficiency of 48.5% was determined.