NiFeO<sub>x</sub> decorated Ge-hematite/perovskite for an efficient water splitting system.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 34262036.
- Also identified by DOI 10.1038/s41467-021-24428-7 and PMC identifier 8280122.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
To boost the photoelectrochemical water oxidation performance of hematite photoanodes, high temperature annealing has been widely applied to enhance crystallinity, to improve the interface between the hematite-substrate interface, and to introduce tin-dopants from the substrate. However, when using additional dopants, the interaction between the unintentional tin and intentional dopant is poorly understood. Here, using germanium, we investigate how tin diffusion affects overall photoelectrochemical performance in germanium:tin co-doped systems. After revealing that germanium is a better dopant than tin, we develop a facile germanium-doping method which suppresses tin diffusion from the fluorine doped tin oxide substrate, significantly improving hematite performance. The NiFeO<sub>x</sub>@Ge-PH photoanode shows a photocurrent density of 4.6 mA cm<sup>-2</sup> at 1.23 V<sub>RHE</sub> with a low turn-on voltage. After combining with a perovskite solar cell, our tandem system achieves 4.8% solar-to-hydrogen conversion efficiency (3.9 mA cm<sup>-2</sup> in NiFeO<sub>x</sub>@Ge-PH/perovskite solar water splitting system). Our work provides important insights on a promising diagnostic tool for future co-doping system design.